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Transcript of Final Report
MAE 475
Flight Vehicle Design
Final Report
DESIGN OF A MULTI-ENGINE BUSINESS TURBOPROP AIRCRAFT
Submitted by:
The Left βrothersAnthony Donzella
Justin HruskaWyatt Trevithick
Joseph WongNels Lofgren
December 6th, 2016
Table of ContentsList of Symbols...............................................................................................................................iv
1 Mission Summary....................................................................................................................1
2 Comparative Aircraft...............................................................................................................1
2.1 Piper Cheyenne II XL.......................................................................................................22.2 Cessna 425 Corsair & Conquest 1....................................................................................32.3 Piper PA-42.......................................................................................................................42.4 Piaggio Avanti Evo...........................................................................................................52.5 Beechcraft King Air c90GTx............................................................................................6
3 Estimation of Gross Takeoff Weight.......................................................................................7
3.1 Mission Weight Estimates................................................................................................73.1.1 Determination of Regression Coefficients.................................................................7
3.1.2 Determination of Mission Weights............................................................................8
3.1.3 Determination of Parameters.....................................................................................8
3.1.4 Spreadsheet Calculation of Mission Weights............................................................9
3.2 Takeoff Weight Sensitivity Analysis..............................................................................123.3 Recommendations...........................................................................................................14
4 Wing Loading and Performance............................................................................................15
4.1 Performance Constraints.................................................................................................154.1.1 Takeoff Distance......................................................................................................15
4.1.2 Landing Distance.....................................................................................................16
4.1.3 Single Engine Climb................................................................................................16
4.1.4 Begin and End Cruise..............................................................................................17
4.1.5 Cruise Power Required and Power Installed...........................................................18
4.2 Recommendations...........................................................................................................185 Wing Design..........................................................................................................................19
5.1 Comparative Study of Similar Aircraft...........................................................................195.2 Main Wing Design..........................................................................................................20
5.2.1 Airfoil Selection.......................................................................................................20
5.2.2 Aspect Ratio.............................................................................................................20
5.2.3 Thickness.................................................................................................................20
5.2.4 Sweep.......................................................................................................................21
5.2.5 Taper Ratio..............................................................................................................21
i
5.2.6 Incidence and Twist.................................................................................................21
5.2.7 Dihedral...................................................................................................................22
5.2.8 Stall..........................................................................................................................22
5.2.9 Results......................................................................................................................22
5.3 Drag Analysis..................................................................................................................245.4 Recommendations...........................................................................................................26
6 Layout and Design of Fuselage.............................................................................................27
6.1 Design of Fuselage..........................................................................................................276.2 Results and Spreadsheet Analysis...................................................................................296.3 Fuselage Layout..............................................................................................................306.4 Recommendations...........................................................................................................31
7 Empennage Design................................................................................................................31
7.1 Horizontal and Vertical Tail Design...............................................................................317.1.1 Airfoil Selection.......................................................................................................31
7.1.2 Aspect Ratio.............................................................................................................32
7.1.3 Thickness.................................................................................................................32
7.1.4 Sweep.......................................................................................................................32
7.1.5 Taper Ratio..............................................................................................................33
7.1.6 Tail Placement for Stall/Spin...................................................................................33
7.1.7 Results......................................................................................................................34
7.2 Drag Analysis..................................................................................................................377.3 Recommendations...........................................................................................................37
8 Engine Selection and Performance........................................................................................38
8.1 Engine Selection.............................................................................................................388.2 Performance....................................................................................................................428.3 Recommendations...........................................................................................................44
9 Takeoff and Landing Performance........................................................................................44
9.1 CDo Calculation................................................................................................................449.2 Takeoff Performance.......................................................................................................45
9.2.1 Thrust.......................................................................................................................46
9.2.2 Lift...........................................................................................................................47
9.2.3 Drag.........................................................................................................................47
9.3 Landing Performance......................................................................................................53
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9.4 Recommendations...........................................................................................................5510 Enhanced Lift Devices...........................................................................................................55
10.1 Types of Flaps.............................................................................................................5510.2 Leading and Trailing Edge Flap Design......................................................................5810.3 Recommendations.......................................................................................................63
11 Structural Design...................................................................................................................63
11.1 Refined Wing Analysis...............................................................................................6311.2 Wing Load Analysis....................................................................................................6511.3 Fuselage Load Analysis...............................................................................................6911.4 Fuselage Design..........................................................................................................7211.5 Recommendations.......................................................................................................72
12 Stability and Control..............................................................................................................73
12.1 Longitudinal Stability..................................................................................................7312.2 Lateral Stability...........................................................................................................7812.3 Directional Stability....................................................................................................7812.4 Rudder Sizing..............................................................................................................80
13 Engineering Conclusions and 3 View Drawings...................................................................82
References......................................................................................................................................84
Appendix A – Request of Proposal...............................................................................................85
Appendix B – Gross Takeoff Weight............................................................................................87
Appendix C – Weight Analysis.....................................................................................................90
Appendix D....................................................................................................................................93
Appendix E – Drag Calculations...................................................................................................96
Appendix F – Empennage Design.................................................................................................98
Appendix G – Power Requirements............................................................................................100
Appendix H – Engine Performance.............................................................................................102
Appendix I - Takeoff...................................................................................................................106
Appendix J - Landing..................................................................................................................117
Appendix L – Refined Weight.....................................................................................................121
Appendix M – Wing Loading......................................................................................................123
Appendix N – Structural Analysis...............................................................................................125
Appendix O – Stability Analysis.................................................................................................127
Appendix P – 3 view drawing.....................................................................................................131
iii
List of SymbolsSymbol Description Units
a Acceleration ft/s2
Aprop Area of propeller ft2
a.c Aerodynamic center --AR Aspect Ratio --b Wing span ftbf flap spanB Breguet range factor --
Bend Breguet endurance factor --c Chord length ft
CD0 Zero lift drag coefficient --Cdi Induced drag Coefficient --Cf Skin friction coefficient --Cfl Skin friction drag coefficient --Cl 2D lift coefficientCL 3D lift CoefficientCLα Lift curve slope --D Drag lbs
Dprop Diameter of propeller fte Oswald’s efficiency factor --E Hold time hoursF Form factor --Ff Friction force lbffn Fuel fraction at phase n of flight --H Placement Height ft
HT Horizontal tail --iw Incidence angle of wing deg.K Flap design constants --l length ftL Lift force lbLD n
Lift to drag ratio at phase n of flight --
LP Landing Parameter --M Mach number --
MAC/m.a.c Mean aerodynamic chord ftn Load factor --
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Symbol Description Units
P Power HPq Dynamic pressure lb/ft2
Q Interference factor --r radius of fuselage ft.R Range N.mi.Re Reynolds number --
ROC Rate of Climb ft/mins Structural factor --
Sref Planform area of wing ft2
Swet Wetted area of wing ft2
sfc Specific fuel consumption lbf /hrhp
Sn Ground roll at takeoff or landing ftT Thrust lbf
t/c Thickness ratio --TOGW Takeoff gross weight lbs.
Tvto Thrust at takeoff lbf
Δt Change in time hoursVn Velocity at n phase of flight fpsVT Vertical tail --Wn Weight at n phase of flight lbs.W/S Wing loading lbs/ft2
W/P Power loading lb/HPXac Aerodynamic center location ftXcg Center of gravity location ftΔy Leading edge sharpness --
αstall Stall angle of attack deg.α0L Zero lift angle of attack deg.flaps Flap deflection deg.
Γ Dihedral angle deg.ε Wing twist deg.
ηprop Propeller efficiency --λ Taper ratio --Λn Sweep angle at n location on wing deg. Coefficient of friction --ν Kinematic viscosity ft2/sρ Density sl/ft3
σTU Ultimate stress psi
v
1 Mission SummaryThis is the final report in a series of reports that documents the conceptual design of a long
range, multi-engine turboprop aircraft in response to the RPF shown in Appendix A. The enclosed report shows the entire design process which includes comparative aircraft study, estimation of gross takeoff weight, wing loading/performance, wing design, layout and fuselage design, tail design, engine selection, takeoff and landing performance, enhanced lift selections, structural design, and stability and control. All calculations and raw data can be found in the appendix section presented at the end of the report.
Due to a recent marketing study, Beechcraft Inc. stated that there is a strong demand for a long range multi-engine turboprop business class propeller driven aircraft. The capabilities and specifications are shown below in Table 1.1.
Table 1.1: Mission RequirementsRange (NM) 1000
Holding (contingency) fuel 30 minutes
Reserve fuel 45 minutes
Design Cruise Speed (knots) 320 @ 25,000ft
Payload
6 passengers arranged in luxury seating (36" seat pitch) plus crew
(pilot and copilot)
FAR Takeoff Distance (ft) 2,000
FAR Landing Distance (ft) 2,000
As can be seen in the above table the aircraft must be spacious enough for luxury seating of 6 passengers as well as a 2 passenger crew. The aircraft must also be capable of achieving a cruise speed of 320 knots at an altitude of 25,000 feet. The desired range of the aircraft is to be 1000 nautical miles with a contingency fuel of 30 minutes and a reserve capacity of 45 minutes. The take-off and landing distances are set to be 2,000 feet in accordance with the Federal Aviation Regulations (FARs).
2 Comparative AircraftThe following aircraft have been chosen to be studied in order to provide a basis on which to
design a new aircraft given the mission specifications: Piper Cheyenne II XL, Rockwell Aero Commander 500 Series (500s Shrike Commander), Cessna 441 Conquest II, AAC Angel, and the Beechcraft King Air c90GTx. These particular aircraft were selected on their similarities in flight requirements and capabilities as an aircraft. Of each aircraft, pertinent data in regards to its performance, specifications, and components are discussed below.
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2.1 Piper Cheyenne II XL
Table 2.2: Manufacturing SpecificationsWTO (lbf) 9474WP (lbf) 4053WE (lbf) 5487WL (lbf) 7600
Pmax (HP) 1240
Powerplant Make/Modelx2 Pratt and Whitney (UACL) PT6A-135
VCruise (knts) 255VMax (knts) 275
Range (N.M) 1175Fuel Capacity (U.S. gal) 366
Table 2.3: Aircraft Geometry & Aerodynamic DataSREF (ft2) 229W/S (psf) 41.37
AR 7.95Wing Sweep (°) 5
Tail Config. ConventionalPower Loading
(lbf/HP) 7.64
Structure Factor 0.58
Figure 2.1: Piper Cheyenne II XL
2
2.2 Cessna 425 Corsair & Conquest 1
Table 2.4: Manufacturing SpecificationsWTO (lbf) 8600WP (lbf) 3652WE (lbf) 4948WL (lbf) 8000
Pmax (HP) 1000
Powerplant Make/Model 2x P&W PT6A-112
VCruise (knts) 251VMax (knts) 263
Range (N.M) 1576Fuel Capacity (U.S. gal) 366
Table 2.5: Aircraft Geometry & Aerodynamic DataSREF (ft2) 225W/S (psf) 38.2
AR 8.60Wing Sweep (°) 0
Tail Config. ConventionalPower Loading
(lbf/HP) 8.60
Structure Factor 0.58
Figure 2.2: Cessna 425 Corsair/Conquest 1
3
2.3 Piper PA-42
Table 2.6: Manufacturing SpecificationsWTO (lbf) 11200WP (lbf) 4811WE (lbf) 6839WL (lbf) 10330
Pmax (HP) 1440
Powerplant Make/Model x2 P&W PT6A-41
VCruise (knts) 282VMax (knts) 314
Range (N.M) 2241Fuel Capacity (U.S. gal) 578
Table 2.7: Aircraft Geometry & Aerodynamic DataSREF (ft2) 293W/S (psf) 38.23
AR 6.43Wing Sweep (°) 5
Tail Config. T-TailPower Loading
(lbf/HP) 7.78Structure Factor 0.57
Figure 2.3: Piper PA-42
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2.4 Piaggio Avanti Evo
Table 2.8: Manufacturing SpecificationsWTO (lbf) 12100WP (lbf) 2300WE (lbf) 8375WL (lbf) 11500
Pmax (HP) 1630
Powerplant Make/Model 2 P&W PT6A-66B
VCruise (knts) 366VMax (knts) 402
Range (N.M) 1370Fuel Capacity (U.S. gal) 438
Table 2.9: Aircraft Geometry & Aerodynamic SpecificationsSREF (ft2) 172.22W/S (psf) 70.26
AR 11.96Wing Sweep (°) 1
Tail Config. T-TailPower Loading
(lbf/HP) 7.42Flap/Slat Config. CanardsStructure Factor 0.69
Figure 2.4: Piaggio Avanti Evo
5
2.5 Beechcraft King Air c90GTx
Table 2.10: Manufacturing SpecificationsWTO (lbf) 10485WP (lbf) 2108WE (lbf) 5804WL (lbf) 9832
Pmax (HP) 1100
Powerplant Make/Model2x Pratt & Whitney Canada PT6A-135A
@ 550 shp eachVCruise (knts) 226VMax (knts) 272
Range (N.M) 1260Fuel Capacity (U.S. gal) 384
Table 2.11: Aircraft Geometry & Aerodynamics DataSREF (ft2) 295W/S (psf) 35.54
AR 9.76Wing Sweep (°) 5.69
Tail Config. ConventionalPower Loading
(lbf/HP) 9.53
Flap/Slat Config. Flaps on Approach
Structure Factor 0.55
Figure 2.5: Beechcraft King Air c90GTx
6
3 Estimation of Gross Takeoff WeightThe purpose of this section is to provide an estimation for the gross takeoff weight of the
conceptual design aircraft. Fuel fraction method and Breguet equations will be used for the estimation of mission weights, and analyzed in a sensitivity analysis of the takeoff weight estimation.
3.1 Mission Weight EstimatesThe method used in calculating the amount of fuel burned during certain flight phases was the fuel fraction method. This approach uses a ratio defined as the weight entering a phase divided by the weight leaving that phase. Then the products of the individual fuel fractions for each phase is equal to the total fuel fraction for the entire mission. The Breguet Range Factor is a calculated value that is used in the determination of the weight of an aircraft in its cruise phase. Similarly, the Breguet Endurance Factor is a calculated Value used in the determination of the weight of the fuel consumed during the holding phase.
3.1.1 Determination of Regression Coefficients
A very vital part in the design process of an aircraft is the determination of the structure factor (s). s is defined as the ratio of the empty weight of the aircraft to the takeoff weight of the aircraft. This is represented in Equation 3.1.
(3.1)
Using this equation, a plot of the takeoff weight versus the structure factor was created by varying the structure factor of the aircraft and then determining the new takeoff weight for that specific structure factor. This plot is shown in Figure 3.1.
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0.5 0.52 0.54 0.56 0.58 0.6 0.62 0.64 0.66 0.68 0.75500
10500
15500
20500
25500
30500
35500
f(x) = 52394893.8839223 x⁴ − 119027799.871473 x³ + 101440529.180396 x² − 38384237.4912745 x + 5442456.23697006
Iterated Takeoff Weight Iterated Takeoff Weight TrendlinePiper Cheyenne Piper Pa-42King Air c90gtx Cessna 425Piaggio Avanti
Structure Factor
WTO
(lbs
)
Figure 3.1: Structure factor calculations
Looking at the plot in Figure 3.1, the takeoff weight begins to rapidly increase proportionally to an increase in the structure factor. The structure factors of our comparable aircraft were also plotted onto this trend in order to determine the best structure factor to use. Looking at the points for the comparable aircraft as well as the takeoff weight trend line, a structure factor of 0.58 was chosen for the design.
3.1.2 Determination of Mission Weights
To determine the weights of the aircraft during the multiple phases of the missions, a spreadsheet analysis was carried out. This spreadsheet took the mission requirements as well as the calculated parameters to calculate useful values that would then be used in determining the mission weights of each phase via the fuel fraction method. This method is essentially the ratio of the aircraft leaving a phase to the weight of the aircraft at the beginning of that phase. Using the fuel fraction allowed the team to come up with a Takeoff Gross Weight (TOGW) through an iterative process in the spreadsheet.
3.1.3 Determination of Parameters
The determination of parameters was conducted after an in-depth look at aircraft comparable to that which is being designed. During the determination of the set parameters, the team selected values which correspond with the required payload, takeoff distance, and landing distance constraints outlined in the original RFP.
3.1.3.1 Determination of specific fuel consumption
When determining the specific fuel consumption to be used in the calculations, the team had to keep in mind that, per the RFP, the choice of engines for this aircraft were limited to the Pratt &
8
Whitney PT6 series or Garrett TFE series. Therefore, for the given engines and their manufacturer’s data, a value of 0.58 was assigned to this variable.
3.1.3.2 Choosing the design Aspect Ratio
When analyzing similar long range, multi-engine turboprop business class propeller driven aircraft models, it was observed that the typical range was from seven, for smaller light aircraft such as the AAC Angel, up to roughly ten for larger payload aircraft such as the Beechcraft King Air c90GTx. When choosing the design aspect ratio, it was important to choose a wing large enough to meet the required takeoff distance constraint whilst also avoiding too large of a wing in order to avoid higher fuel consumption and efficiently cruise at the desired speed stated in the RFP. All variables considered, the team chose an aspect ratio of eight in order to meet all aforementioned design specifications.
3.1.3.3 Choosing of the zero lift drag coefficient
The dimensionless parameter CDo is directly related to the form drag, or zero lift drag of the aircraft, which is dependent on the geometry of the aircraft itself. Due to the complexity of the calculations involving the approximation of CDo, a range of typical values for similar aircraft was provided to the class, with values ranging from 0.0220 for clean, well-designed aircraft to 0.0260 for less aerodynamically clean aircraft. It was decided by the team to assume a value of 0.0230 allowing for a small degree of variation from the optimal value of 0.0220 or less.
3.1.3.4 Choosing of W/S
Before choosing a design wing loading, three specific situations were taken into consideration: takeoff and landing, single engine climb, and W/S for optimum cruise. Wing loading influences the landing parameter, LP, which is also found in the landing distance Equation 3.2
(3.2)
A higher wing loading, such as fifty, leads to longer takeoff distance which may conflict with the design requirement of a 2,000 foot takeoff distance. On the opposite side, too low of a wing loading, such as thirty, means a much larger wing area and significantly larger drag produced at the design cruise speed of 300 knots at 25,000 feet altitude. Due to fuel burn, the weight of the aircraft entering and exiting cruise will vary greatly meaning that the wing loading will ultimately affect the wing sizing as well. When considering the wing loading in a single engine situation one must keep in mind FAR pt. 135-187 in which it is stated that an aircraft in a single engine climb must be able to climb at a flight path angle of at least 2.4°, however for this design the flight path angle minimum will be considered at 3.3° instead.
3.1.4 Spreadsheet Calculation of Mission Weights
In this section, the flight phases and calculations leading to the weight of the aircraft at different phases as well as the final takeoff gross weight will be explained. To be able to come a final gross takeoff weight, a spreadsheet that calculates the weight of the aircraft at each section of the missions was created. The final TOGW is found through an iterative process. This means that the
9
weight is guessed and then checked until a suitable value is reached. After the first TOGW was entered, Equation 3.3 was used to find the weight after takeoff.
W after ¿¿=W ¿ ∙ ff ¿ (3.3)
In this equation, the entered TOGW is multiplied by the fuel fraction at takeoff to come to a final weight after takeoff. A fuel fraction of 0.98 was selected based on similar values. After this weight was calculated, the weight of the fuel used during that phase could be calculated as the difference between the TOGW and the weight after the takeoff. This is shown in Equation 3.4.
W F , ¿¿=W ¿−W after ¿¿ (3.4)
The next phase was the climb and then acceleration to cruise. This phase is similar to the first phase and thus Equation 3.3 was modified to be used during this phase and is represented in Equation 3.5.
W After climb=W after ¿¿ ∙ ff climb (3.5)
The product of the weight after the takeoff and the fuel fraction for climb gives you the weight of the aircraft after the climb phase. A fuel fraction of 0.98 was selected based on similar values. Just like the previous phase, the fuel used during climb is the difference between the weight entering the phase and the weight leaving the phase shown in Equation 3.6.
W F , climb=W after ¿¿−W after climb (3.6)
The next phase of the flight was the cruise phase. In order to calculate the fuel used during the cruise section, the range and the Breguet Range Factor (B) were needed. The range is known to be 1000 nautical miles from the mission requirements and the Breguet Range Factor can be calculated using equation (3.7).
B=326 ∙ η¿ ∙LD Actual
∙ 1sfc (3.7)
In equation (3.7), η¿ is the efficiency of the propeller, LD Actual
is the actual Lift to Drag Ratio, 1
sfc
is the inverse of the engine’s standard fuel consumption, and 326 is a conversion factor from statute miles to nautical miles.
After B was found, the fuel used during cruise could be calculated using Equation 3.8.
W F , cruise=(1− 1
eRB
) ∙W start , cruise (3.8)
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In Equation 3.8, R is the range in nautical miles, B is the Breguet Range Factor, and the weight entering cruise is the same as the weight after the climb. Now with the fuel for cruise found, the weight after the cruise phase is just the difference of the weight entering cruise and the fuel used during the cruise expressed in Equation 3.9.
W after cruise=W enter cruise−W F, cruise (3.9)
The next phase entered is the Descent and Landing phase. This phase returns to using the fuel fraction method and is shown in Equation 3.10.
W after descent=W after cruise ∙ ff descent (3.10)
A fuel fraction of 0.975 was selected based on similar values. The fuel used during this phase is the difference between the weight after cruise and the weight after the descent. This is shown in Equation 3.11.
W F , descent=W after cruise−W after descent (3.11)
The next phase was the reserve phase, in order to calculate the fuel used in the reserve phase Equation 3.12 was used.
W F , Res=
sfc ∙ ΔtLD Max
∙ W Res ∙ V LD Max
550
(3.12)
In Equation 3.12, sfc is the engine’s standard fuel consumption, Δt is the time in reserve in
hours, LD Max
is the maximum lift to drag ratio, W Res is the weight entering the reserve, V LD Max
is the
velocity for the maximum lift to drag ratio, and the 550 is a conversion factor.
After the fuel of the reserve is found, the weight after the reserve can be found as the difference between the weight after descent and the weight of the fuel in reserve, shown in Equation 3.13.
W after res=W afterdescent−W F , res (3.13)
The last weight needed to be calculated is the fuel during the holding phase. The equation used to calculate this is expressed as Equation 3.14.
W F , Hold=(1− 1
eE
Bend
)∙ W enter hold (3.14)
In Equation 3.14, E is the time in hold in hours, Bendis the Breguet endurance factor, and W enter hold is the weight entering the hold which is the same as the weight leaving the reserve. The Breguet Endurance Factor is calculated using Equation 3.15.
11
Bend=1
sfc∙ L
Dmax∙ 1
V hold (3.15)
In Equation 3.15, sfc is the engine’s standard fuel consumption, LDmax
is the maximum lift to drag
ratio, and V hold is the velocity in the hold.
Now with the weight of fuel used in hold the total fuel weight can be expressed as the sum of all the fuel used over the all the phases. And then the total fuel and payload weight is the weight of the fuel used added with the weight of the passengers and their baggage shown in Equation 3.16.
W F , Payload=W F+W payload (3.16)
Now the weight available for the structure of the aircraft could be calculated, shown as Equation 3.17.
W avail .=W ¿−W F , Payload (3.17)
Also the weight required to build the structure can be calculated using Equation 3.18.
W req .=W ¿ ∙ s (3.18)
Equation 3.18 is simply the TOGW multiplied by the structure factor s. and Equation 3.17 is the difference of the TOGW and the available structure. The difference between Equation 3.18 and Equation 3.17 will tell you whether you have a surplus of weight (positive) or a deficient of weight (negative). If you have a surplus, structure can be removed meaning the TOGW can be reduced, and if you have a deficient structure must be added increasing the TOGW. Using these equations and the given parameters, a final Gross Takeoff Weight of 9520 pounds was found.
3.2 Takeoff Weight Sensitivity AnalysisThis sensitivity analysis was conducted by varying range, aspect ratio, and zero lift drag coefficient. This was done in order to see how the listed parameters would affect the TOGW. The takeoff estimate calculations will be calculated using the values in TTaable 3.1.
Table 3.12: Sensitivity analysis parameters.CDo 0.0180 0.0210 0.0240 0.0270
Range (NM) 500 1000 1500
AR 5 7 9
A simple Matlab code (Appendix C) was constructed to vary each of the parameters while holding other values constant. This led to three graphs with three data sets on each graph. The different graphs correspond to the range of the aircraft; while the data sets on each graph correspond to the varying Aspect Ratio of the aircraft wing.
12
Figure 3.2 shows aspect ratio and CDo varied while the range of the aircraft is held at 500 NM. This figure shows as CDo increases, the weight of the aircraft increases linearly due to rise in used fuel during cruise, which is caused by a decrease in L/Dmax from the increase of total drag on the aircraft. If an exponential trend line is added to the data for AR= 5 the slope can be expressed as y=4797.6e13.723x, this value can be used to compare the other two figures.
0.0170 0.0190 0.0210 0.0230 0.0250 0.027052005400560058006000620064006600680070007200
AR=5 AR=7 AR=9
CDo
TOG
W (l
bs)
Figure 3.2: Varying Aspect Ratio and Drag Coefficient at range of 500 NM
Figure 3.2 shows aspect ratio and CDo varied while the range of the aircraft is held at 1000 NM. A similar trend from figure 3.1 is shown in this figure. However, there are some differences. One difference is the increase in weight with increasing CDo changes with greater exponential. Another difference is the increase in range of TOGW. This is due to the need for more fuel to travel the increased range. If an exponential trend line is added to figure 3.3 for AR=5 the slope can be expressed as y=4492.8e34.303x, this shows that the slope has increased from e13.723 to e34.303.
13
0.0170 0.0190 0.0210 0.0230 0.0250 0.02705800
6800
7800
8800
9800
10800
11800
AR=5 AR=7 AR=9
CDo
TOG
W (l
bs)
Figure 3.3: Varying Aspect Ratio and Drag Coefficient at range of 1000 NM
Figure 3.4 shows aspect ratio and CDo varied while the range of the aircraft is held at 1500 NM. Again, a similar trend from figure 3.3 is experienced, the main difference is the increase in weight with increasing CDo changes with greater exponential than figure 3.3 and figure 3.1. If adding an exponential trend line to Figure 3.4 is done again, the slope is shown as y=2762.9e82.498x, which is a greater increase from e34.303 previously seen between Figure 3.3 and Figure 3.2.
0.0170 0.0190 0.0210 0.0230 0.0250 0.02705800
10800
15800
20800
25800
30800
AR=5 AR=7 AR=9
CDo
TOG
W (l
bs)
Figure 3.4: Varying Aspect Ratio and Drag Coefficient at a range of 1500 NM
3.3 RecommendationsWith the initial comparative study of aircraft with similar mission specifications complete, the second stage of the design may begin. The first step towards building a functional aircraft is to
14
find the gross takeoff weight available for the aircraft. The first step is to estimate an initial value for the gross takeoff weight. The fuel fraction method is then used to find the weight of the fuel burned in the phase. The fuel fraction method assigns each phase of flight an individual fuel fraction to compensate for the fuel burned. Of the given flight phases, the takeoff, climbing, and the descent and landing phases have fuel fractions assigned to be 0.99, 0.98, and 0.975 respectively. The two other phases, cruise and holding, involve calculations for the fuel consumed that involve the aerodynamics and aircraft geometry as well as the Breguet Range Factor and the Breguet Endurance Factor.
Following these steps will produce the total weight of fuel burned, which can then be used to find the available empty weight. A structure factor is then selected and used in order to find the required empty weight for the structure of the aircraft. With the calculations complete for both the available and required empty weights calculated, a comparison is done, and then the takeoff gross weight is then changed until the available and required empty weight have the same value.
The amount of fuel burned was found to be 2,398 pounds and the empty weight available was finalized at 5,522 pounds after taking the passengers, crew, and baggage into consideration. This led to the final take off gross weight to be 9,520 pounds.
4 Wing Loading and PerformanceThis section focuses on the calculations of the wing loading for the aircraft, as well as
other performance constraints such as: the wing loading, lift to drag ratio at both the beginning and end of cruise, the takeoff distance, the landing distance, and other performance constraints for the designed aircraft.
4.1 Performance Constraints In accordance with parameters laid out in the RFP, and in compliance with FAR requirements, the aircraft to be designed must be meet two specific criteria with respect to takeoff and landing distance respectively. The designed aircraft must meet the FAR specified requirement of being able to both land, and takeoff in a distance of 2,000 feet or less. In addition, the single engine climb must also be analyzed to ensure FAR criteria are met, thus allowing aircraft certification. One must take into consideration the design wing loading whilst optimizing the aircraft cruise.
4.1.1 Takeoff DistanceOne determining the estimated takeoff distance, one must collect several important quantities: the wing loading, W/S, the thrust to weight ratio for takeoff, T/W, the previously calculated CLmax, and the ratio of takeoff air density to standard sea level density, σ. One may calculate the thrust required at takeoff using the following formula,
T VTO=[ (SHP∗ηp )V ¿
]∗550(4.1)
Where SHP is the horsepower produced by a single engine on the aircraft, the 550 term is for conversion of units from horsepower, prop efficiency is a predetermined value for the selected propeller of the aircraft, and Vto is calculated using the following relation,
15
V ¿=1.2 (V stall ) (4.2)
The thrust to weight ratio is then obtained by dividing the calculated thrust value by the TOGW of the aircraft.
With this value in hand, one may progress to the calculation of the Takeoff Parameter of the aircraft, T.O.P, using Equation 4.3,
T . O . P .=[ (WS )( TW ) ]( 1
CLmax∗σ )
(4.3)
The resulting value is then substituted into the following relation for calculating takeoff distance,
S¿=[20.9 (T . O. P ) ]+87∗√T .O. P .( TW )
(4.4)
4.1.2 Landing Distance
Recalling from the RFP, the required landing distance is equal that of the required takeoff distance of 2,000 feet. As with the takeoff calculation, one must calculate a landing parameter, LP, using previously obtained values in the following equation,
LP=(WS )( 1
CLmax∗σ ) (4.5)
The closed form solution for determining the landing distance is far less complex than that of the takeoff distance, using only constant values in addition to the LP,
SL=118 LP+400 (4.5)
4.1.3 Single Engine Climb
Parameters involving and related to single engine climb are especially important since they affect the ability of the aircraft to be certified or not, specifically that in an engine out condition, per FAR Pt. 135-187, the aircraft, “...must be able to climb at =3.3 degrees.” To ensure the ability of the aircraft to meet this mandate, a minimum glide path slope of =3.3 degrees was used in the single engine calculations.
Primarily affect by single engine climb due to the loss of thrust, is the climb velocity, Vse,climb. The adjusted value is calculated using the following,
V se climb=V L
D max
−15 knts (4.6)
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And may then be used to calculate the adjusted single engine rate of climb, ROC, in units of feet per minute using,
ROC=(V seclimb) [sin (Γ )] (60 ) (4.7)
Where the outstanding constant of 60 is for version to the time units of minutes.By rearranging the total drag equation,
D=D i+D 0 (4.8)
And substituting in the following expressions for Di and Do, respectively,
Di=[(W
S )W ]q∗π∗AR∗e
(4.9)
D0=W∗q∗CD0
(WS ) (4.10)
It can be shown that a quadratic solution to the estimation of (W/S) may be found using the quadratic formula with respect to (W/S) as a variable, yielding the following expression,
1.2(WS )=
[( TW
−G)±√( TW
−G)2
−( 4 CD0
π∗AR∗e )]( 2
q∗π∗AR∗e )(4.11)
If one observes the two resulting solutions to this quadratic expression, a low value of (W/S) and high value of (W/S) are given. This range represents the range of wing loadings which will allow for satisfactory takeoff capability with a single engine. Any wing loading below the lowest value will not succeed because not enough lift will be generated by the wing to achieve takeoff. Any value selected which is higher than the max wing loading from the equation will also lead to failure since the wing will generate too much drag and keep the aircraft from successfully taking off.
4.1.4 Begin and End Cruise
In order to appropriately determine wing sizing, one must analyze the design aircraft at two points: starting cruise and ending cruise. Since the largest portion of fuel is burned while the
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aircraft is in cruise, the weight of the aircraft will fluctuate significantly when comparing the weight entering cruise to that of exiting cruise. For example, from the spreadsheet in Appendix A, the proposed aircraft enters cruise at a weight of approximately 9,143 pounds and exits cruise weighing 7,459 pounds. If one holds the wing loading, (W/S), constant for both weights, as shown in Appendix A, one would find two different ideal wing areas, Sw. However, the ideal wing sizes to optimize performance are not nearly large enough for an aircraft with the given design weight and payload capacity.
4.1.5 Cruise Power Required and Power Installed
With several power plant options provided in the RFP, including commercially available gas turbine motors such as Pratt & Whitney PT6 series or Garrett TFE series engines, a precise model has yet to be selected for the design aircraft. Nonetheless, performance calculations deem it necessary to estimate several parameters involving power in flight to compare with the required thrust to climb at a given flight path angle, Γ. One should investigate the Power required for cruise, Pcruise@altitude, Pinstalled, and the Single engine power required for climb at Γ.
To accurately determine the power required for cruise one must input the drag, propeller efficiency, and cruise velocity into the following formula,
Preq=1ηp
(D∗V cruise ) (4.12)
Notice as well that since the aircraft is flying at altitude and not in sea level conditions, the installed power may be found by multiplying the required power by the ratio of the local density to that of standard sea level air,
Pinstalled=Preq( ρactual
ρSSL) (4.13)
To find the single engine power required for climb at , only must simply divide the single engine horsepower in half and add a constant value as shown below,
Pse climb@ Γ=( SHP
2 )+40 (4.14)
When looking to compare the power installed per engine, one may derive the required thrust to climb at a flight path angle Γ from the following,
T req=( ηp∗PSEreq, climb@Γ
V SEclimb)550 (4.15)
This series of calculations allow for further comparison of the theoretical aircraft single engine performance to that which is required in the federal aviation regulation.
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4.2 RecommendationsBased on the calculations above, the design was determined to have design parameters consisting of the values listed in Table 4.1.
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Table 4.13: Key design parameters and ground rollWTO (lbs) 9520 Preq cruise end (HP) 909Sref (ft2) 226.67 Pinstall (HP) 2414T/W 0.339 W/S 42s ground roll landing (ft) 2223 s ground roll TO (ft) 2118
The given design restrains were taking off and landing within 2000ft, however with the design parameters chosen the ground roll on takeoff and landing are slightly higher than the design restraints. This can be fixed later in the design process by adding flaps and airbrakes, thus increasing the CL during landing and takeoff.
5 Wing DesignThis section documents the design of the Main wing of the aircraft. Components of the wing
design include: Airfoil selection, selection of the Aspect ratio, Thickness of the wing, Sweep angle, taper ratio, incidence and twist, Dihedral angle, as well as stall calculations. Included in this report as well, is the drag analysis of the selected airfoil and of the designed main wing. Including the zero lift drag, Induced drag, and the wing contribution to the total drag.
5.1 Comparative Study of Similar AircraftIn order to provide a basis on which to start the design of the wing for the aircraft, two of the five aircraft that were researched prior to the design phase were selected. These two aircraft, the Piper Cheyenne II XL and the Beechcraft King Air c90GTx, have similarities and differences when it comes to its wing configurations. This data and comparison of the data will provide a more accurate starting point for the wing design of the newly designed aircraft.
Table 5.1 is an in depth breakdown of the dimensions and different aspects of the wing. These dimensions include the span, aspect ratio, wing loading, wing reference area, and sweep angle. This table will provide an idea for an appropriate value for each different facet of the wing design.
Table 5.1: Wing Planform Data
Span, b (ft)
Aspect Ratio, AR
Sweep, Λ (°)
Reference Area, Sref (ft2)
Wing Loading, W/S (psf)
Piper Cheyenne II XL 42.69 7.95 5.00 229 41.37
Beechcraft King Air c90GTx 53.67 9.76 5.69 295 35.54
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5.2 Main Wing Design5.2.1 Airfoil Selection
For the design of the aircraft wing, a six series NACA airfoil was chosen. The six series was chosen because these airfoils were designed so the region over which the airflow remains laminar is maximized. This greatly decreases the drag over the wing. The airfoil chosen was the NACA 63-212. Table 5.2 displays the airfoil data and Figure 5.1 shows the airfoil.
Table 5.2: Design Airfoil dataName NACA 63-212 Cdo 0.0035
Clmax 1.35 rle 0.0024
Cla 0.1096 Cl minD 0a.c. 0.35 (t/c)max 35%
aoL (deg) -2 t/c 12%
Figure 5.1: 2D shape of the NACA 63-212 Airfoil
5.2.2 Aspect Ratio
For the wing design an aspect ratio of 8 was chosen. In choosing this value the length of the wing could be calculated using Equation 5.1
(5.1)
5.2.3 Thickness
To calculate thickness, t/c is used. This is the thickness over the total chord length. With the NACA 63-212 the thickness is 12% located at 35% back from the leading edge. Using these values the maximum thickness at the root and tip can be calculated using Equation 5.2
(5.2)
With tx being the thickness at 35% chord at any position on the wing with cx being the chord length at that position, x.
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5.2.4 Sweep
The purpose of adding sweep to an aircraft wing design is to lower the effective Mach number on the aircraft wing to reduce the overall load on the wing. Since this aircraft design will be traveling much slower than Mach 1, the design does not need any sweep at the leading edge. If sweep at the leading edge was brought into the design, the effective Mach speed would be described by Equation 5.3.
(5.3)
Since the leading-edge sweep will be considered to be zero for this design, the sweep at any location along the wing can be calculated using equation 5.4.
(5.4)
Listed in Table 5.3, values of sweep at important points along the wing can be found. This will be used to ensure the design of the wing is properly constructed.
Table 5.3 Sweep angle calculated at important locations along the wing.ɅLE 0
Ʌ1/4 chord -3.44420251
Ʌt/c max -4.81632341ɅTE -13.5358564
5.2.5 Taper Ratio
Taper ratio is described as the ratio between the length of the chord at the tip and of the root, as shown in equation 5.5. Adding taper ratio to the design minimizes the lift at the tips of the wing. This, in turn, minimizes the strength of the vortices developed at the wingtips of the aircraft. A perfect taper ratio design, is an elliptical wing. This design properly distributes the lift to minimize the effects of overflow at the tips of the wing. However, an elliptical wing is impractical and expensive. An alternative is a taper ratio with the range of [0.25~0.45]. For this aircraft wing, a value of 0.35 was selected.
(5.5)
5.2.6 Incidence and Twist
Incidence angle and twist both have a direct effect on the amount of lift that is generated. Twist also has an added benefit of allowing for smooth stall characteristics. This is because if a negative value of twist is added to the wing design, the tips of the wing will be at a lower angle of attack than that of the root, this ensures that the root of the wing will be stalling before the
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tips. This is important because added twist limits the chances of a tip stall, which could result in an unrecoverable spin.
First, twist must be calculated using Equation 5.6 so that the value can be used in Equation 5.7 to calculate incidence angle.
(5.6)
(5.7)
In Equation 5.6, ε being the twist angle is chosen in order to achieve a change in angle of attack. For this wing design a twist of -2° was selected. This ensures that the coefficient of lift needed for cruise is achieved by changing α, which will be iw, or wing incidence. The value of twist can be manipulated to achieve a smaller, or higher angle of incidence. For this wing design the wing is at an angle of incidence of 1.86°.
5.2.7 Dihedral
Dihedral, ᴦ, can be added to a wing design to achieve sideslip stability. For this wing design a dihedral angle of 3.5° was used. Typical values range from [2~6°].
5.2.8 Stall
Considering the dihedral and twist added to the wing design of this aircraft, the aircraft should handle relatively well during a stall. Calculating the stall angle and speed of this aircraft can be done using Equations 5.8 and 5.9 respectively.
(5.8)
(5.9)
5.2.9 Results
After considering the above conditions, the final design of the aircraft wing is displayed in Table 5.4. The values that the team considered the most important are presented below, the rest can be seen in Appendix D.
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Table 5.4: Table of important values displaying wing properties
AirfoilNACA 63-212 S(ft2) 226.67 AR 8 ɅTE -13.5
b(ft) 42.58 iw(deg) 1.86 ε(deg) -2 L/D 22.062
cr (ft) 7.89 ɅLE 0.0 ᴦ(deg) 3.5 αstall (deg) 14.6
ct (ft) 2.76 Ʌ1/4 chord -3.4 ʎ 0.35Vstall
(ft/sec) 236.76m.a.c. (ft) 5.73 Ʌt/c max -4.8
A Solidworks model of the aircraft wing designed was created. Figures 5.2-5.5 display this.
Figure 5.2: Front view of the aircraft wing. In this view the dihedral angle and twist is clearly shown.
Figure 5.3: Side view of the aircraft wing. This shows the dihedral, as well as the taper of the wing.
Figure 5.4: Top view of the aircraft wing. This view clearly shows the sweep at the leading and trailing edges, as well as
the taper.
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Figure 5.5: 3D View of aircraft wing design
5.3 Drag AnalysisTo accurately model the drag produced by the wing planform, one must take into consideration all elements of the wing which directly affect the drag. However, the appropriate terms and atmospheric conditions must first be collected for proper inspection.
Table 5.5: Viscous DragV (ft/sec) 540.8q (lb/ft^2) 155.8836531Re 10276015.74
CF 0.002927452
Swet(ft2) 462.270798
F 1.439534461Q 1
Viscous Drag
As displayed in Table 5.5, the parameters considered are as follows, in order from top to bottom: cruise velocity, dynamic pressure, cruise Reynolds number, skin friction coefficient, wetted planform area, form correction factor, and interference factor.
Since the wing reaches a cruise Mach number of roughly 0.48, there is no need for a leading edge wing sweep since transonic speeds are not approached until near a cruise Mach of 0.7. The dynamic pressure at cruise is calculated using the well-known formula of,
25
(5.10)
And the cruise Reynolds number using the kinematic viscosity, nu, was determined via,
(5.11)
When determining the overall skin friction coefficient of the wing, one must consider both the laminar flow section and the section of the wing in which the flow trips to turbulent. Using the following relations for laminar flow skin friction and turbulent flow skin friction respectively, the overall coefficient is the sum of the two received values.
(5.12)
(5.13)
For an approximation of the wetted surface are of the wing, since the t/c ratio is greater than 5%, the team used,
(5.14)
The closed form solution for the computation of the form fact, F, was retrieved Design of Aircraft and is given by the following,
(5.15)
The design team also chose to affix a low wing, well filleted wing to the fuselage yielding an interference factor of 1.
With the necessary parameters allocated, one may delve further into the calculation for the total drag due to the wing by now determining the zero lift drag coefficient of the wing, C Do, and the induced drag coefficient of the wing at the beginning and end of cruise, CDibeg and CDiend
respectively, since the lift required changes as fuel is burned during cruise.
Using the collected terms, the zero lift drag coefficient of the wing may be found via,
(5.16)
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And the two induced drag coefficients may be calculated using the Munks relation,
(5.17)
Where the aspect ratio, Oswald’s efficiency, and cruise lift coefficients have already been determined in previous reports.
From this point, calculating the respective drags is done trivially by multiplying the drag coefficients times the cruise dynamic pressure, and wing area. The only difference is the usage of the Cdi and CD0 coefficients in the equation,
(5.18)
Table 5.6: Summary of DragCDO Wing 0.00859Cdi(begin cruise) 0.00313Cdi(end cruise) 0.00209Cd,total 0.01381Induced Drag(begin cruise) 110.745 lbfInduced Drag(end cruise) 73.6997 lbfZero Lift Drag 303.675 lbfTotal Drag 488.12 lbf
Diligently setting up the analysis as stated in this section, for the designed aircraft, one comes to the following numerical values seen in Table 5.6.
5.4 RecommendationsAfter comparable aircraft, such as Piper Cheyenne II XL and the Beechcraft King Air c90GTx, were studied, the team came up with a spreadsheet that was capable of predicting the parameters of the wing, as well as perform a beginning drag analysis on the aircraft. Selection of the Airfoil to be used was debated by the team and ultimately decided upon the NACA 63-212 to be used. A taper ratio of 0.35 was added to the wing design to minimize the lift at the tips and stop the aircraft from tip stalling. The team also decided that the addition of a dihedral angle of 3.5 degrees would help to combat any possible slide slip instability the aircraft may encounter.
With the wing parameters in place, a drag analysis was able to be performed. Using the calculations shown in section 4 of the report, the team came up with an induced drag of 110.745 pounds at the beginning of cruise, and 73.6997 pounds at the end of cruise. As well as the induced drag, a zero lift drag due to the wing with a magnitude of 303.675 pounds was calculated. With all of the values taken into consideration, the total drag on the aircraft was found to be 488.12 pounds.
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6 Layout and Design of FuselageWith the wing-design complete, the fuselage is the next step in the design of the aircraft;
then the drag forces on the fuselage can be found.
6.1 Design of FuselageIn order to properly design the fuselage for the concept aircraft, a myriad of considerations were taken into account. First and foremost, the aircraft must comfortably sit six passengers and two crewmembers along with their luggage. Additionally, the engine and avionics placement, payload accommodation, landing gear placement, fuel storage, wing attachment and carry through, and fuselage shape must all be considered. The team also chose to use the Sears-Haack relation, seen below, from Design of Aircraft to model the fuselage shape for drag calculation purposes:
[ r (x)r (0) ]
2
=[1−( 2xl )
2]3/2
(−l /2≤ x≤ l /2) (6.1)
Beginning with payload accommodation, the team chose to arrange the passengers in a conventional fashion: three rows of two seats with one seat on each side of the aisle. After deliberation the team felt this choice to be the most efficient arrangement of the payload due to its simplicity and optimization of personal space, as any other arrangement would require unnecessary elongation or widening of the fuselage. The crew manning the aircraft will be situated towards the nose of the aircraft with sufficient room for two individuals.
Following the deliberations on payload accommodation, the next topic discussed was the ideal placement of the landing gear for the aircraft. To allow for fuel storage in the wing, and provide uninhibited area for wing placement and carry through, the team chose to select a tripod configuration with a nose wheel and one outboard on each wing, as seen on the Piper Cheyenne III for example. Due to the large volume of space taken up by the carry through spar, the landing gear on the wings will be placed slightly aft of the main wing spar.
Since the model of engines to be used has been narrowed down to a select group, commercially available gas turbine motors such as the Pratt & Whitney PT6 series or Garrett TFE series engines, the only remaining issue to be resolved was the placement of the engines on the fuselage or body. After analyzing similar aircraft and their successes or failures respectively, such as the failure of the Antonov 28 and success of the Piper Cheyenne, the team decided upon wing mounted, streamlined nacelles for the engines.
As consistently seen in most aircraft, the nose of the aircraft will serve as the housing for the avionics package, with displays shown in the cockpit as seen below:
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Figure 6.1: Cockpit Display of Comparative Aircraft
Fuel storage is one of the paramount design considerations with respect to the fuselage. With various types of tanks, each with their own respective effectiveness, as seen in Table 6.1,
Table 6.1: Volume EffectivenessFuel Tank Type Fuselage WingDiscrete 100% -Bladder 83% 77%Integral 93% 85%
The team debated on the placement of the fuel storage container in either the wings or fuselage first. For safety concerns, in case of a crash to avoid any unnecessary fire hazard, the team sided with housing the fuel tanks in the wings. And though it requires more intricate containment, the team chose to select inboard, integral wing tanks to take advantage of the space available in the wing and to also take advantage of the higher effectiveness as compared to an amorphous bladder tank. With the adjustment from the 85% effectiveness of the integral wing tank, the total volume for fuel storage in the wing is 56.3 ft3.
Table 6.2: Ergonomic Dimensions of the Interior
Seat Width22.00
in
Seat Pitch34.00
in
Minimum Aisle Width
16.55
in
Using the minimum aisle width required as a basis and after comparing the average seat width and pitch provided, the team chose the values seen in Table 6.2 for the internal arrangement.
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Table 6.3: Fuel and Wing Volumetric PropertiesTotal Fuel used (lbs) 2398.227Total Fuel required (gal) 357.944Total Fuel required (ft3) 47.850
Volume Required (ft3) 56.295Wing Volume (ft3) 98.240
With a given range desired and the specific weight of the fuel being known, the total fuel required can be found by dividing the weight of fuel burned by the specific weight and is detailed in Table 6.3. Even with the additional volume needed due to integral wing tanks, there is sufficient space in the wing for the fuel to be stored.
6.2 Results and Spreadsheet AnalysisTo calculate the drag caused by the fuselage, the fuselage was broken down into ten sections; each with an equal width of 3.6 feet. At each section, the Reynolds number is calculated at the midpoint of each section. The skin friction for each section is then calculated using the equation:
(6.2)
Equation 3.1 is for turbulent flow and is used instead of the laminar flow skin friction equation due to the high Reynolds number at cruise velocity creating turbulent flow on the fuselage. The drag at each section is calculated using the equation:
(6.3)
The total drag on the fuselage is the summation of all the section drag forces. The full calculations can be seen in Appendix A. The calculated drag on the fuselage can be seen in Table 6.4.
Once the total drag is calculated, the fuselage zero lift drag can be calculated. This is done using the equation:
(6.4)
The result of this calculation is shown in Table 6.4.
Table 6.4: Drag SummaryDrag (lbs) 178.7CD0 0.005056
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6.3 Fuselage Layout Included in this section are; the fuselage dimensions, seating arrangement, and baggage area.
Figure 6.2: Top view of the seating arrangement and dimensions.
As displayed in Figure 6.2, the seating arrangement meets the required one foot aisle width, as described by the FAA, with an aisle width of 1.38 feet. This arrangement also features luxurious reclining leather seats in the front two seats, while the four in the rear have ample leg room, all having a seat pitch of 3.6’ or 43”. The luggage compartment is located in the rear of the aircraft so it does not limit the amount of head room for the passengers. This luggage compartment can hold six standard carry-ons (9” x 14” x 22”). The rear door is located directly in front of the baggage area, so that passengers can easily place their luggage in the compartment and continue onto the aircraft. Figures 6.3-6.4 show the fuselage layout, seating arrangement, and dimensions in feet.
Figure 6.3: Side view of the seating arrangement.
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34.27”
16.55”
17.44”
7.92”
Figure 6.4: Isometric view of the seating arrangement and baggage compartment.
6.4 RecommendationsAfter a complete design of the shape of the fuselage with the seating arrangements included, the drag analysis was conducted to determine the drag coefficient and the drag force on the fuselage alone. The drag force on the fuselage alone was calculated to be 178.7 pounds and the drag coefficient was 0.005056.
7 Empennage DesignThis section will include a detailed explanation of the horizontal and vertical tail design, which includes the airfoil, aspect ratio, thickness, sweep, taper, and placement. As well as the design of the empennage section, a drag analysis will be performed on the proposed design that includes the drag and zero lift drag on both the horizontal and vertical tail sections.
7.1 Horizontal and Vertical Tail DesignThe conventional layout of the horizontal and vertical tail was selected for the design of this aircraft. This design was selected due to the aircraft cruise velocity being subsonic. So a non-conventional design of the horizontal tail was not needed. This configuration was selected also due to the configuration requiring less structural support and having a lower overall weight as a result.
7.1.1 Airfoil Selection
For both the horizontal and the vertical tail, a symmetric airfoil was desired. Since a conventional design is used, a thin airfoil can be used since not as much structural is needed as compared to a configuration like the T-Tail configuration. The NACA 64-004 was selected as a
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result of these requirements. Table 7.1 shows the properties for the NACA 64-004. This Airfoil was selected since the airfoil is symmetric and has a low thickness ratio.
Table 7.1: NACA 64-004 properties
Clmax 0.8Clalpha(/deg) 0.11
t/c 8%a.c. 0.26
αoL (deg) 0
7.1.2 Aspect Ratio
The aspect ratio for the horizontal and vertical tail was selected based from historical data of similar aircraft as provided by Corke. Using these ranges, the selected aspect ratios are shown in Table 7.2.
Table 7.2: Selected aspect ratiosARVT 2.0ARHT 3.0
7.1.3 Thickness
Due to the use of the conventional tail configuration, a thin airfoil can be used. As such, the airfoil selected has a maximum thickness of 4% of the chord length.
7.1.4 Sweep
The sweep angles for the horizontal tail were designed such that the trailing edge sweep angle is zero. These angles were calculated using the equation:
(7.1)
The results of the calculations are shown below in Table 7.3.
Table 7.3: Horizontal-tail sweep angles
Sweep AnglesΛLE (deg) 29.80Λ1/4 (deg) 23.26ΛTE (deg) 0.07
Λt/c max(deg) 18.99
The vertical tail sweep angles selected and calculated to have a negative trailing edge sweep angle. A leading-edge angle of 40.6 degrees was selected and equation 7.1 was used to calculate
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the sweep angles throughout the vertical tail. The results of these calculations are shown below in Table 7.4.
Table 7.4: Vertical-tail sweep angles
Sweep AnglesΛLE (deg) 40.60Λ1/4 (deg) 32.73ΛTE (deg) 0
Λt/c max(deg) 27.21
7.1.5 Taper Ratio
The taper ratio was selected based off of the general range of similar aircrafts as provided by Corke. The selected aspect ratio for both the horizontal and vertical tail is 0.4. The Selected aspect ratio is then used to calculate the root and tip cord lengths of the horizontal and vertical tail. This is done using the equations:
(7.2)
(7.3)
(7.4)
Where:
(7.5)
(7.6)
The horizontal and vertical tail coefficients are selected based from values as described by Corke for a twin turboprop aircraft.
7.1.6 Tail Placement for Stall/Spin
To enhance stall control, the horizontal tail should be placed such that the horizontal tail in not inside the wake of the main wing. Based off the recommended placement of the horizontal tail from NACA, Table 7.5 shows the positions used for the placement of the horizontal tail. The horizontal distance is the distance from the mean aerodynamic center of the main wing to the mean aerodynamic center of the horizontal tail. The vertical distance is the distance above the mean aerodynamic center of the main wing.
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35
Table 7.5: Horizontal tail placementlHT (ft) 20.55HHT (ft) 0
To enhance spin control, the vertical tail should be placed such that the horizontal tail’s wake created during spin has the least amount of flow over the vertical tail. With a recommended minimum of 30% of the vertical tail outside of the horizontal tail wake. As such, the Vertical tail was positioned 18.55 feet behind the mean aerodynamic center of the main wing.
7.1.7 Results
The results of the calculations described for the horizontal tail and the vertical tail are shown in table 7.6 and table 7.7 respectively. Figures 7.1 through 7.8 show the top view, side view, front view, and an isometric view of the tail configuration to scale.
Table 7.6: Horizontal tail calculationsSweep Angles Viscous Drag Calculations
ΛLE (deg) 29.80 Cf 0.002871 SHT (ft2) 126.10Λ1/4 (deg) 23.26 RE 11609803 b (ft) 19.45ΛTE (deg) 0.07 Swet (ft2) 254.543 cr (ft) 9.26
Λt/c max(deg) 18.99 F 1.3002 ct (ft) 3.70Q 1 ARHT 3.00
CDo HT 0.0037 Xac HT (ft) 2.39D (lbf) 148.1205 β 0.76
CLα 0.0589m.a.c (ft) 6.88
Table 7.7: Vertical tail calculationsSweep Angles Viscous Drag Calculations
ΛLE (deg) 40.60 Cf 0.003 SHT (ft2) 65.79Λ1/4 (deg) 32.73 RE 10270618 b (ft) 11.47ΛTE (deg) 0 Swet (ft2) 132.805 cr (ft) 8.19
Λt/c max(deg) 27.21 F 1.278 ct (ft) 3.28Q 1 ARHT 2.00
CDo HT 0.0037 Xac HT (ft) 2.11D (lbf) 77.460 β 0.80
CLα 0.0456m.a.c (ft) 6.09
Figure 7.1: Front view of the horizontal tail
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Figure 7.2: Isometric view of the horizontal tail
Figure 7.3: Right side view of the horizontal tail
Figure 7.4: Top view of the horizontal tail
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Figure 7.5: Front view of the horizontal tail
Figure 7.6: Isometric view of the horizontal tail
Figure 7.7: Top view of the horizontal tail
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Figure 7.8: Right view of the horizontal tail
7.2 Drag AnalysisWhen considering the zero lift drag of both the horizontal and vertical tails, that the previously used method for determining the zero lift drag coefficient of the wing planform may be adapted to these cases as well, after slight adjustment of parameters of course. Since symmetric airfoils are generally implemented for the horizontal and vertical tail shapes, the drag is directly dependent on the zero lift drag of the airfoil shape. The resulting simplifications yield the following expression, which is usable for both components,
D=q SW C f FQ (7.7)In this instance, q is the in-flight dynamic pressure, Sw is the wetted area for each respective surface, Cf is the skin friction coefficient, F is the form factor for each component, and Q is the interference factor of each component.
Having already solved for the in-flight dynamic pressure in the preliminary design phase, one may move forward to the determination of the wetted surface area. As with the wing planform, the wetted area is a function of the t/c of the selected area and the design reference area. The skin friction drag coefficient is a summation of the laminar flow and turbulent flow components of the previously stated equations for the skin friction drag coefficient. The form factor is determined from a closed form expression previously presented in the design of the wing planform, and also seen on page 75 in the Corke textbook Design of Aircraft. And finally, the interference factor is an assumption with a value of one for well-fileted members.
Table 7.8: Empennage Drag Analysis
Total Value Drag (lbs) CDo
Horizontal Tail 151.623 0.00380Vertical Tail 69.80865 0.00340
After careful deliberation, the following values, presented in Table 7.8, show the estimated drag and zero lift drag coefficient for each component of the empennage.
7.3 RecommendationsTaking into consideration the type of aircraft that is being designed, and the prior wing design and fuselage design, a conventional tail design was decided to be the best option for the aircraft. Based on the calculations above, the geometric parameters of the horizontal and vertical tail were determined and are presented in tables 7.9 and 7.10 respectively
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Table 7.9: Horizontal Tail Geometry
SHT (ft2) 153.40
b (ft) 21.45
cr (ft) 10.22
ct (ft) 4.09
ARHT 3.00
Table 7.10: Vertical Tail Geometry
SVT (ft2) 36.43
b (ft) 7.39
cr (ft) 7.04
ct (ft) 2.82
ARVT 1.50
Also following the aforementioned calculations, the contribution to zero lift drag from each tail and the total drag from the tails is shown in tables 7.11 and 7.12.
Table 7.11: Horizontal Tail Drag
CDo HT 0.0069
D (lbf) 166.0514
Table 7.12: Vertical Tail Drag
CDo VT 0.0073
D (lbf) 126.1305
8 Engine Selection and PerformanceThe performance of the engine will be calculated from the stall speed to the cruise speed
of 350 knots. This calculation will be carried out at four altitudes which include sea level, 8,000 feet, the cruise altitude of 25,000 feet, and 31,000 feet. In addition to these calculations an analysis of the rate of climb for a single engine will be carried out to ensure the aircraft is in accordance with FAR regulations.
8.1 Engine SelectionIn order to select an appropriate engine for the designed aircraft, the total drag, both zero lift drag and induced drag, while operating at cruise conditions must be computed. This has been a running calculation when each component of the aircraft is designed, making this a simple summation of the zero lift drag forces from the wing, fuselage, and the empennage. The only piece missing, is the nacelle; which can be found by using equation 8.1 and then multiplied by two since there are two engines on board.
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(8.1)
Table 8.1: Total drag summationComponent D (lbs)Wing 312.3
Fuselage 141.1
Horizontal Tail 148.1
Vertical Tail 77.5Nacelle 29.4
Induced Wing 92.2Total 800.6
Zero
Lift
Table 8.1 shows the zero lift drag contribution from each of the previously discussed aspects of the aircraft design, as well as the induced drag from the wing. This results in a total drag force acting on the aircraft at cruise conditions. Table 8.2 reflects the drag coefficients for the same components.
Table 8.2: Total drag coefficient summationComponent CD
Wing 0.008838Fuselage 0.0039925
Horizontal Tail 0.003733
Vertical Tail 0.0037417Nacelle 0.000835
Induced Wing 0.00261Total 0.0237503
Zero
Lift
With the total drag, the power required at cruise can be found using Equation 8.2.
(8.2)
After calculating the power required at cruise, the shaft power can then be found by relating the power required, and the propeller efficiency, which is assumed to be 0.85. This relating is seen in Equation 8.3.
(8.3)
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With the shaft horsepower required at cruise known, the shaft horsepower at sea level can be found using Equation 8.4, which compensates for the change in power produced by the engine with the change in density. This trend in power drop with altitude increase is plotted in Figure 8.1.
(8.4)
0 5000 10000 15000 20000 25000 30000 35000 40000 450000
1000
2000
3000
4000
5000
6000
7000
8000
Altitude (ft)
Pshp
reqd
SSL
(HP)
Figure 8.1: Trend of shp required at SSL as a function of altitude
The next power requirement comes from the rate of climb. This is found using Equation 8.5 which relates the rate of climb to the power available and the power required in regards to the weight of the aircraft.
(8.5)
From here the additional power required to climb at 1,000 feet per minute can be found by using Equation 8.6 And then can be used to find the installed power for the aircraft in Equation 8.7.
(8.6)
(8.7)
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The above calculations in Equations 8.6 and 8.7 are summarized in Table 8.3.
Table 8.3: Summary of power requirementsPreqd 25,000 ft (HP) 883.66
Pshp reqd 25,000 ft (HP) 1039.60Pshp SSL (HP) 2769.21
Preqd climb (HP) 2065.35Pinstall (HP) 2769.21
With an installed power of about 2800 HP, an engine selection of 1400 HP is selected. Given the list of engines and their performance provided, the T58-GE-100 engine is selected, which is produced by General Electric. Its shaft horsepower is 1500 HP which is an ideal selection for the design of the aircraft. Figure 8.2 shows the T58-GE-100, and Table 8.4 shows the dimensions and specific fuel consumption of the engine.
Table 8.4: T58-GE-100SFC at Full Power [lb/(HP*hr)] 0.61
Max Env. Diameter (in) 20.9Max Env. Length (in) 55
Figure 8.2: T58 Engine and its internal components (Goebel)
The next design consideration is with an engine out condition. As discussed in class, these type of aircraft have complications when climbing with only one engine operable. With an engine out and the specific engine selected, 1500 HP remains. Using equation 2.5 and solving for the power required using a rate of climb of 250 FPM, a required horsepower of 1200 HP is found. Which is lower than the HP available, meaning the aircraft meets the minimum requirements for climbing while operating at engine out conditions. The results for this calculation can be seen in Table 8.5.
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Table 8.5: Calculations at engine out conditionsROC (FPM) 250
ηP 0.85Pavail (HP) 1500
Preqd climb (HP) 1202.9
With the power requirements calculated, and an appropriate engine selected, the final thing necessary is the placement on the wing. Given an average 8-foot diameter propeller and a one-foot clearance from the tip of the propeller to the fuselage, this places each engine 5 feet from the fuselage, or 7.625 feet from the center of the wing (given the fuselage diameter of 5.25 feet. The placement can be seen in Figure 8.3.
Figure 8.3: Engine Placement on Wing
8.2 PerformanceUsing the parameters shown in table 8.6 and the performance parameters of the T58-GE-100, a spreadsheet was created to determine the required shaft horsepower as well as the Rate of climb. These were calculated using the equations:
(8.8)
(8.9)
The full spreadsheets for the calculations at standard sea level, 25000 ft., and 31000 ft. can be seen in Appendix H. Figure 8.4 shows the effect that the altitude has on the required shaft horse power. It can be seen that, in general, a higher altitude will require more horsepower. Figure 8.5 shows that a higher cruise velocity will result in a lower rate of climb. This is due to having less excess horsepower to climb since more is needed to cruise at a higher velocity. Figure 8.6 is like figure 8.5 however, figure 8.6 shows the rate of climb with one engine out.
Table 8.6: Aircraft parametersW (lbs) 9520Sref (ft2) 226.67E 0.85AR 8ηprop 0.85
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Figure 8.4: Required shaft horsepower vs. Cruise velocity at sea level and altitudes
50 100 150 200 250 300 350-1000
0100020003000400050006000700080009000
10000
SSL 25000 ft
Vcr (fps)
ROC
(fpm
)
Figure 8.5: Rate of Climb vs. cruise velocity at sea level and 25000 ft
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50 100 150 200 250 300 350-4000
-3000
-2000
-1000
0
1000
2000
3000
4000
5000
SSL 25000 ft
Vcr (fps)
ROC
(fpm
)
Figure 8.6: Single engine rate of climb vs. cruise velocity
8.3 RecommendationsIt is important to note that for engine selection, one not only consider the cruise performance at altitude but also for takeoff and landing at standard sea level conditions, were the most power is required, in terms of the shaft horsepower. After considering both the zero lift drag and induced drag of all components on the aircraft, it was determined that the proposed aircraft will require 1039.60 shaft horsepower at 25,000 feet. Using provided equations, this determination was extrapolated to an installed horsepower requirement of 2769.21 horsepower. Rounding up to a total of 2800 horsepower, the team then sifted through the list of available engines and found multiple viable options. Ultimately, the T58-GE-100 was selected which provides a shaft horsepower of 1500 horsepower. The extra available thrust allows for the aircraft to comfortably meet the single engine climb requirements demanded by Federal Aviation Regulations for this type of aircraft.
9 Takeoff and Landing PerformanceThe goal of this section is to determine the overall takeoff and landing distances. Each
section will go into detail the exact process to determine these values. With the full spreadsheets shown in the appendices. Along with the takeoff and landing performance, the overall zero lift drag coefficient is calculated with and without the landing gear.
9.1 CDo CalculationThroughout the iterative design process of the aircraft, a crucial parameter that was calculated at every instance was the zero lift drag coefficient. Now that the design for the wing, fuselage, and empennage sections are completed, the total zero lift drag can be found by taking a total summation of each sections zero lift drag coefficient. This is shown in equation 9.1.
(9.1)
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In this equation, the zero lift drag coefficients are for the fuselage, three-dimensional wing, horizontal tail, vertical tail, and the nacelles respectively. Two zero lift drag tables were created, one for the takeoff configuration which includes an estimate of the contribution of the landing gear on the aircraft, table 9.1, and one for the zero lift drag seen during flight with the landing gear retracted, table 9.2. Each table includes the sections zero lift drag coefficient, total zero lift drag coefficient, and the percentage contribution of that section to the total drag.
Table 9.14: Take-off Zero Lift Drag CoefficientCDof 0.0051 10.71%
CDoW 0.0088 18.49%
CDoHT 0.0039 8.19%
CDoVT 0.0038 7.98%
CDoNac 0.0010 2.10%
CDoGear 0.0250 52.52%
CDo TO 0.0476 100.00%
Table 9.2: Flight Zero Lift Drag Coefficient
CDof
0.0051 22.57%
CDoW
0.0088 38.94%
CDoHT
0.0039 17.26%
CDoVT
0.0038 16.81%
CDoNac
0.0010 4.42%
CDo Flight
0.0226 100.00%
Looking at the above tables, it can be seen that the landing gear practically doubles the value of the zero lift drag. Disregarding the landing gear, the aircraft’s wing provides the highest contribution to the zero lift drag at approximately 39%, and the total zero lift drag coefficient in flight being .0226. This total CDo is about 24 counts less than the initial guess at the beginning of the design process.
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9.2 Takeoff PerformanceOnce all of the parameters such as engine power calculations and wing and empennage sizing have been completed a takeoff performance analysis can be created by using a numerically integrated spreadsheet in which takes into account all of the design parameters decided upon previously. There are many calculations that will go into this numerically integrated “flight simulator” in order to determine takeoff performance parameters such as ground roll.
9.2.1 Thrust
When creating the numerically integrated spreadsheet it is necessary to start with calculating static thrust. Static thrust is calculated using equation 9.2.
(9.2)
This equation for static thrust includes the area of the disk of the propeller. In this specific aircraft design the diameter of the propeller is 8 feet, which makes the area of the propeller 50.25 ft2. This static thrust calculation is used until the dynamic thrust calculation using equation 9.3 equals the static thrust condition. Once this occurs the dynamic thrust equation is adopted throughout the rest of the performance calculation. The thrust calculations can then be broken into x and y components using equations 9.4 and 9.5.
(9.3)
(9.4)
(9.5)
However, before dynamic thrust can be calculated the velocity of the aircraft must be determined. This is done using equation 9.6 and equation 9.7 for velocity in the x and y directions. The resultant velocity is determined using equation 9.8
(9.6)
(9.7)
(9.8)
In order to calculate the velocity components however, the aircraft acceleration will also need to be calculated. The acceleration calculations for x and y components are displayed in equations 9.9 and 9.10
(9.9)48
(9.10)
For the acceleration equations the thrust in the x and y directions is known for the static case, however the lift, drag, and friction force is still needed in order to calculate the acceleration. The friction force can be found using equation 9.11, however the lift force is still missing from this equation and will be explained in detail in the preceding section.
(9.11)
In this specific design, the coefficient Kspoiler is one since there are no spoilers being deployed during takeoff. In equation 3.1.10 the coefficient of friction is estimated to be 0.04. This equation is the frictional force due to the wheels touching the runway surface.
9.2.2 Lift
To calculate the acceleration, velocity, and position of the aircraft the lift must first be determined. This is done by first calculating the resultant lift for the speed given. This is shown in equation 9.12. In Equation 9.12, q, dynamic pressure and the coefficient of lift, must also be calculated. This is done using Equations 9.13 and 9.14.
(9.12)
(9.13)
(9.14)
Since CLα is known for the coefficient of lift equation it is necessary to calculate the effective angle of attack of the aircraft. This is done by using Equation 9.15. Once this is found, it can be applied to Equation 9.14 to find the coefficient of lift at a specific angle of attack.
(9.15)
Now that the lift force can be calculated, the resultant force will need to be broken into x and y components to apply them to equations 9.6 and 9.7, the acceleration x and y components. In order to do this the flight path angle, γ, must be found. The flight path angle can be calculated using equation 9.16 and applied to equations 9.17 and 9.18 to break the lift force into x and y components.
(9.16)
49
(9.17)
(9.18)
9.2.3 Drag
The next variable that is needed within the acceleration calculation in equations 9.9 and 9.10 is the drag force. To calculate this, first the coefficient of drag of the aircraft must be found.
(9.19)
Equation 9.20 can be used to find the change in the coefficient of drag when the landing gear are extended.
(9.20)
Equation 9.21 is used to find the induced drag.
(9.21)
Once the drag coefficient is calculated, then equation 9.22 can be used to find the drag force and then this can be broken down into x and y components using equations 9.23 and 9.24
(9.22)
(9.23)
(9.24)
Now that all of the necessary values are needed in order to calculated acceleration and velocity, equations 9.25 and 9.26 can be used in order to calculate position in x and y in order to determine takeoff distance and height.
(9.25)
(9.26)
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Table 9.3 shows the static thrust, takeoff weight, ground roll to achieve takeoff, and distance in order to clear the FAA defined 35ft tree at the end of the runway.
Table 9.3: List of important takeoff parametersWTO 9520
Tstatic (lbs) 7079.2
W/S 42.0
Sx to clear obstacle (ft) 1373.4
Sx ground roll (ft) 1026.1
Table 9.4 shows the thrust on the aircraft at three speeds during takeoff. The speeds are 0, 50 knots, and 1.2Vstall
Table 9.4: Thrust for Certain Speeds during takeoffVelocity (ft/s) Thurst (lbs)
0 6505.183.39 6505.1176.8 6505.1
Figure 9.1 shows the change of use of the static thrust calculation against the dynamic thrust calculations and the velocity at which the two equations intersect. This also displays the change in thrust as the velocity increases.
0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 400.0 450.0 500.00.0
1000.02000.03000.04000.05000.06000.07000.08000.0
Airspeed (fps)
Thru
st (lb
s)
Figure 9.6: Thrust versus airspeed
Figure 9.2 displays the flight profile in the x and y direction and the rotation point of the aircraft can clearly be shown. The orange dot shows where the aircraft reaches 50 feet in height.
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0.0 1000.0 2000.0 3000.0 4000.0 5000.0 6000.00.0
100.0
200.0
300.0
400.0
500.0
600.0
700.0
800.0
900.0
1000.0
X position (ft)
Y P
ositi
on (f
t)
Figure 9.7: Displays the flight profile of the aircraft
Figure 9.3 displays the angle of attack, pitch, and flight path angle versus time. In this plot, the effective angle of attack decreases once the aircraft has established a positive rate of climb and the flight path angle increases due to the pitch and climb rate of the aircraft.
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0 10 20 30 40 50 600.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
Pitch AngleAngle of AttackFlight Path Angle
Time (sec)
Ang
le (d
eg)
Figure 9.8: Angle of attack, pitch, and flight path angle versus time.
In Figure 9.4, it shows the acceleration components of the aircraft. Noticeably the Y acceleration peaks at the rotation time. This is accurate considering the aircraft will be gaining acceleration in the Y direction during takeoff.
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0 10 20 30 40 50 600.0
5.0
10.0
15.0
20.0
25.0
30.0
X AccelerationY Acceleration
Time (sec)
Acc
eler
atio
n (ft
/sec2
)
Figure 9.9: X and Y components of acceleration with respect to time.
Figure 9.5 displays the velocity of the aircraft during takeoff operations. The velocity can clearly be seen to level off during climb.
0 10 20 30 40 50 600.0
50.0100.0150.0200.0250.0300.0350.0400.0450.0500.0
Time (sec)
Vel
ocity
(ft/s
ec)
Figure 9.10. Velocity of aircraft during takeoff with respect to time.
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9.3 Landing PerformanceIn calculating the landing performance of this aircraft, it was paramount to keep in mind that per the RFP, the aircraft must be able to land on a 2000-foot runway. Keeping this parameter in mind, one must move on to analyzing the four primary stages of the landing sequence: approach, flare, free roll, and braking.
Beginning the approach, Federal Aviation Regulation requires aircraft to clear a 50-foot tall obstacle upon approach. Also, note that the standard glide path angle is roughly three degrees. From geometric and trigonometric inspection, one may produce the following equation for the distance covered in approach,
sA=HTR−50
tan γ approach(9.27)
In order to deduce the value for HTR, one must first calculate the radius of the transition via,
RTR=(1.23 V s )
2
0.19 g(9.28)
And with this in hand, the following expression may be used,
HTR=RTR (1−cos γapproach ) (9.29)
For the next sequence, the flare, one may see the distance covered in this sequence as an angular velocity. Accounting for radial components the following expression takes form,
sflare=RTR sin γapproach (9.30)
Once slightly hovering over the landing strip, an aircraft enters the third phase of landing called the “freeroll.” This is the time interval after the flare has been finished and before contact with the ground surface. This phase typically lasts 3 seconds and the distance covered may be calculated using,
sFR=3 V TD (9.32)
Entering the fourth and final phase, the breaking phase, one must numerically integrate basic equations of motion to find the total distance. Firstly, if one sets the datum at the point of contact in this phase, the initial position may then be left as zero feet. This also means that V final is equal to zero and Vinitial is equal to VTD. Now, one must collect the necessary terms in order to properly integrate the terms.
At the point of contact, the wing is still producing lift, the engines are no longer producing thrust, the aircraft still experiences a significant drag force, and there is also a new friction force introduced. For the drag, one must account for the lift induced drag as well as the zero lift drag of the aircraft and additional zero lift drag due to the flaps and the extended landing gear.
The zero lift drag of the aircraft has previously been estimated in prior reports, and the additional zero lift drag due to the flaps is dependent on the type of flaps chosen. This aircraft will use fifty degree deflecting fowler flaps, and the value given in Table 8.3 in Corke, page 164, is given as
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0.0830 for the flaps. Referring to similar aircraft in the initial report, an estimated projected area for the landing gear was found and used to estimate the additional zero lift drag due to the landing gear. The equation used is as follows,
∆ CD 0LG=f LG
ALG
S(9.33)
When the total drag coefficient is determined, one may use the touchdown velocity and dynamic pressure to find the drag at the datum. The lift generated by the wing is proportional to the glide angle and touchdown speed, and the frictional force may be found as a result of finding the lift,
F f=μ (W ¿−LG ) (9.34)
Table 9.5: Additional ParametersμL Dry 0.6μL Wet 0.4CDo fl aps 0.0830CDo LG 0.0215
Table 9.5 shows the relevant terms discussed above.
Progressing onward to the equations of motion,
ax=∑ Forces
Mass(9.35)
sx=(V x 1
2−V x02 )
2ax
(9.36)
Note, since the engines provide no reverse thrust, the forces in the x-direction are only frictional, lift induced, and drag. Since we have already collected these terms for the first station, the datum, and all of these terms are zero at the second station, one may simplify the integration to the above equations.
Table 9.6: Landing DistanceSbraking (ft) 965.620Sapproach (ft) 827.103Sfl are (ft) 254.081SFR (ft) 483.398SL tota l (ft) 2530.203
Table 9.6 shows the calculated numerical values for the design aircraft with respect to each of the four phases of landing, and total distance covered.
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9.4 RecommendationsThe total landing distance is under the required design takeoff distance by approximately six hundred feet. As of now, the aircraft has enough extra takeoff distance and does not currently use flaps during the takeoff. This means that the aircraft can be adjusted if needed and still easily be within the design parameters. This will be useful for the adjustment of the landing distance.
Currently the total landing distance is approximately four hundred feet above the landing distance required as shown in the RPF. This will need to be corrected for to reduce the overall landing distance. This can be done by either changing the trailing edge flaps to reduce the stall velocity. Resulting in a lower touchdown speed, thus reducing the distance needed to brake to a full stop. The other option would be to add a leading-edge device to the wing. This would have a similar effect on the stall speed, resulting in a reduction in the total landing distance.
Overall the aircraft design is proceeding well. All current parameters are within the nominal values. The only current parameter that needs to be adjust is the total landing distance. This will be corrected for as described earlier.
10 Enhanced Lift Devices
This section will serve to document the enhanced lift devices this conceptual aircraft may entail, with the primary goal to determine the leading edge and trailing edge flap design. The discussion section will delve fully into the exact process to determine the design of the flaps. All spreadsheets and complimentary documents will be shown in the appendices.
10.1 Types of Flaps
There are two categories of flaps that will be discussed in this section: they are trailing edge flaps and leading edge devices (LEDs). The trailing edge flaps are broken down into four types the plain flap, split flap, slotted flaps, and fowler flap. The first type, the plain flap, is simply the deflection of the trailing edge of the airfoil section, and is shown in figure 2.1.1. This is the most commonly used trailing edge flap on smaller aircraft.
Figure 10.11: Simple visualization of plain flap
The second type is known as the split flap. The split flap is very similar in design to the plain flap, only that on the split flap only the bottom of the airfoil section is deflected. This is illustrated in Figure 10.2. The lift enhanced lift produced by the split flap is essentially the same as a plain flap, but the drag is known to be larger. Due to this they were a popular addition to aircraft during World War II, but are not used as much in today’s industry.
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Figure 10.2: Simple visualization of the split flap
The third type, the slotted flap, is again a redesign of the plain flap system, and is pictured in Figure 10.3. It includes the addition of a slot at the hinge point to allow for high-pressure air from the lower surface of the airfoil to pass to the upper surface of the flap. This is advantageous due to the boundary layer being able to have added momentum which will allow larger flap deflections before flow separation occurs. In addition, it can also be improved upon by adding more slots which would result in the creation of a double or triple slotted flap. These types of modifications lead to a higher lift coefficient, but can be detrimental to the time frame as they require a complicated construction process.
Figure 10.12: Simple visualization of the slotted flap
The final style flaps is known as the fowler flap. The fowler flap is a modified version of the slotted flap and is shown in Figure 10.4. This means that it includes the same slot and hinge system as the slotted flap, but is capable of translation reward of the airfoil section. This is an advantage because it can effectively increase the wing area of the aircraft.
Figure 10.13: Simple visualization of the fowler flap
The main advantage of these flap systems is that they are capable of increasing the lift coefficient for the aircraft by a sizeable percentage. This would be helpful during the takeoff and landing phases of flight in order to take off in a shorter distance and reduce the amount of distance needed when coming onto the runway for landing. It cannot go without mentioning that the flaps are not only advantageous, but like most things in the real world have disadvantages as well. While the system does increase the lift for a given angle of attack, it does not increase the angle
58
at which the aircraft will stall. It actually does the exact opposite and causes the stall angle to decrease. The results in changes in the location of the stagnation line and pressure gradient at the leading edge surface. This problem was ultimately solved by the creation of the aforementioned LEDs at the beginning of this section.
There are three types of LEDs that will be discussed in this section. They are the leading edge flap, the leading edge Krueger flap, and the leading edge slat. Basically what these devices do is they increase the radius of the leading edge to account for the changes done by the tailing edge flaps.
The first type, the leading edge flap, is essentially the same system and design of the tailing edge flap, but applied to the leading edge. The front of the leading edge would become capable of deflecting downwards. This type of configuration isn’t used all that often for general aviation aircraft, but is utilized in jet application such as on the F-18 due to the high sweep of the wing. Pictured in Figure 10.5 is an example of a leading edge flap.
Figure 10.14: Simple visualization of the leading edge flap
The second type is the Krueger flap. The Kruger flap utilizes and actuator system to deploy only a small surface on the bottom of the leading edge, keeping the main curvature of the leading edge the same, but increasing the camber of the airfoil section which will in turn increase the lift. This is illustrated below in Figure 10.6.
Figure 10.15: Simple visualization of the Kruger flap
The last type of LED, the slotted leading edge flap or slat, is essentially the slotted tailing edge applied to the leading edge, pictured in Figure 10.7. It allows a part of the leading edge to be translated out and the deflected which increases the effective wing area and camber of the airfoil section. From a theoretical stand point it utilizes the same idea of adding momentum to the boundary layer which was described in the slotted flap section earlier. These changes also cause a small change in the angle of attack for zero lift of the aircraft.
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Figure 10.16: Simple visualization of the flat
A downside to the LEDs is they can require the plane to have more construction than was originally though upon. If a budget had been set, and this was not accounted for it could jeopardize the entire build. Another reason this is bad is it could push the structure factor up to a higher value which would change the entire design of the aircraft, so it is crucial to keep these things in mind when the choice of which LEDs will be used, if any.
10.2 Leading and Trailing Edge Flap Design
In the selection process of which types of trailing-edge flaps and leading edge devices, three main points were considered. The first came from comparative aircraft. Most turboprop aircraft utilize plane flaps, and this was one of the driving forces into the selection of plane flaps. The second reason is due to is due to its simplicity, both in design and mathematical computations associated with plane flaps. And the last reason is due to the amount of enhanced lift that’s actually necessary in the overall design of the aircraft. Last report contained calculations towards any necessary additional lift outside of the basic aerodynamics of the aircraft. It was found that there wasn’t a large necessity for enhanced lift, leading to the selection of plane flaps.
The first step in finding the change in the overall lift coefficient, is finding the change due to the trailing-edge flaps. The first step in doing so, involves determining whether the aspect ratio for the main wing is considered high or low. This is determined by Equation 10.1, where C 1 is a constant extracted from Figure 9.8 from Corke which related the constant value to the wings taper ratio.
AR> 4(C1+1 )cos (γ ¿)
(10.1)
If the given relation in Equation 10.1 is proven true, then the wings aspect ratio is considered to be high. The designed aspect ratio is high, which leads to the computation of maximum 3D lift coefficient using Equation 10.2 where the ratio between the maximum 3D and 2d lift coefficient is found using Figure 9.9 from Corke.
CLmax=[ CLmax
C lmax]C lmax
(10.2)
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Table 10.1 summarizes these two calculations and their required values from previous design work.
Table 10.1. 3D lift coefficient design
λ 0.35C1 0.48AR 8.00
Comparative Value 2.703ΛLE 0
CLmax/Clmax 0.9Clmax 1.52CLmax 1.368
Next, the stall angle is found using Equation 10.3 where the last term, change in alpha as a function of maximum lift coefficient, is found using Figure 9.11 in Corke.
α s=CLmax
CLα
+α 0L+∆ αC Lmax
(10.3)
The only missing piece is the leading-edge sharpness value,∆ y , which was found using Figure 9.10 in Corke. The above calculation is summarized in Table 10.2.
Table 10.2. Leading edge sharpness calculations
Δy/c (%) 8.5Δy 0.487Δ⍺CLmax 1.8⍺s (deg) 16.13
The next step is finding the stall angle while the flaps are deployed 40 degrees, which is the designed flap deflection. Equation 10.4 simply adds the change in stall angle, which is found from Figure 9.18 in Corke, to the “un-flapped” stall angle in order to find the “flapped” stall angle can be found, this calculation is summarized in Table 10.3.
α sflapped=αsbasic
+∆ α s (10.4)
Table 10.3. Stall angles of attack
δflap (deg) 40Δ⍺s (deg) -2.8
(⍺s) flapped (deg) 13.33
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In order to find how the flap deflection effects the 2D lift coefficient, a few parameters are necessary; the mean aerodynamic chord, the designed flap chord length, and the percent thickness of the airfoil. Using these values are used in Figure 9.4 in Corke to find the rate of change in the 2D lift coefficient in regards to the flap deflection angle can be found; which will then be multiplied with the designed flap deflection angle to find the newly “flapped” 2D lift coefficient. These values are summarized in Table 10.4.
Table 10.4. Flap deflection angle calculations
mac (ft) 5.73cf (ft) 2cf/c 0.436t/c 12%dCl / dδf (rad)-1 5.35(Clmax)flapped 3.74
Then using Equation 10.5, the change in 2D lift coefficient can be calculated.
∆ C lmax=(C lmax )flapped−(C lmax )basic (10.5)
The final calculation for finding the change in the 3D lift coefficient is set by Equation 10.6, where K is defined in Equation 10.7.
∆ CLmax=∆C lmax
SWF
SWK∆
(10.6)
K∆=[1−0.08 cos2 ( Λc /4 ) ]cos3 /4 ( Λ c/4 ) (10.7)
The above calculations are summarized in Table 10.5
Table 10.5. Change in 3D lift coefficient
ΔClmax 2.22bf (ft) 8SWF 110.97SW 226.67KΔ 0.919ΔCLmax 0.997
The leading-edge devices are much simpler in the calculations. There is only one equation, Equation 10.8, which is fairly similar to the above equation for the trailing-edge flaps.
∆ CLmax=∆C lmax
SWF
SWcos ( Λ¿ )
(10.8)
Where the change in the 2D lift coefficient is a given value with a selected type of leading-edge device, which was selected as a fixed slot leading-edge device. Which leads to the total change in the overall lift coefficient of the aircraft which is a summation of the two values from the leading
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edge and trailing edge. These final calculations towards the change in lift coefficient are summarized in Table 10.6.
Table 10.6. Final lift coefficient changesΔClmax 0.2ΔCLmax 0.0979ΔCLmax 1.095
The increase in the drag coefficient, ΔCD0, is calculated at three different trailing edge flap deflection angles. The angles include a takeoff deflection of ten degrees, and two landing deflection angles of forty and fifty degrees. ΔCD0 is calculated using Equation 10.9:
(10.9)
K1 and K2 are found based off figures provided by Corke. These values can be seen in table 2.2.8. Swf/Sw is the ratio of planform area of the wing with the same span as the flap to the total planform area of the wing. With a flap span of 8ft positioned at the root of the wing, as shown in Figures 10.1-10.3, this ratio becomes 0.4896. Table 10.9 shows K1, K2 and the calculated ΔCD0.
Figure 10.1. Isometric view of the wing with the flaps deployed
Figure 10.2. Placement of flaps on wing
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Figure 10.3. Front view of the flaps deployed
Table 10.7: Calculated ΔCD0 at different flap deflection angles
δf 10o 40o 50o
K1 2 2 2k2 0.0125 0.0875 0.12ΔCD0 0.01223919 0.08567431 0.11749619
The change in the stall angle, Δαs, are determined based off figures provided by Corke. The Δαs
for each angle and the respective stall angles are shown in Table 10.7. The stall angles are calculated by adding the Δαs angle to the stall angle with flaps not deflected. The effect this, and the previously calculated ΔCLmax, has on the lift coefficient with respect to the angle of attack can be seen in Figure 10.4.
Table 10.4: Δαs and calculated αs at different deflection angles
δf 10o 40o 50o
Δαs -0.4o -2.82o -4.27o
αs 15.73o 13.31o 11.86o
-20 -16 -12 -8 -4 0 4 8 12 16 20
-0.5
0
0.5
1
1.5
2
2.5
No Flaps Flaps at 40 degrees
Angle of attack
CL
Figure 10.4: CL vs α with and without flaps
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10.3 Recommendations
All variables considered, the team decided upon the selection of plain flaps as the trailing edge flap design and slotted leading edge flaps, commonly known as flaps. Due to the previously determined landing distance, and noting that the aircraft satisfactorily meets the requirements per the RFP, the team felt simplicity was key. Since both leading edge and trailing edge devices increase the structural load the wing is exposed to minimizing the deadweight becomes key. The chosen arrangements are also much simpler to handle mathematically and mechanically.
11 Structural DesignThis section will serve to document the structural analysis of the wing and fuselage sections
of the aircraft. After the maximum moment for the fuselage is determined the skin thickness and material will be determined. The conclusions section will delve further into the structural analysis results. All spreadsheets and complimentary documents will be shown in the appendices.
11.1 Refined Wing AnalysisThe weight of each component of the aircraft are based off historical weights of the major components. The components to be calculated are the main wing, horizontal tail, vertical tail, installed engine, landing gear, and fuselage. These values are calculated using a multiplier times a factor for each component. These values are provided by Corke and can be seen in Table 11.1. These values provide a very accurate approximation the weight of each component on the aircraft.
Table 11.1: Weights of components of aircraft as multiple of the factorComponent Multiplier FactorMain Wing 2.5 Sw
Horizontal Tail 2.0 Sw
Vertical Tail 2.0 Sw
Installed Engine 1.4 Uninstalled Wengine
Landing Gear 0.057 Wto
Fuselage 1.4 Swet-fuse
When calculating the weight for the landing gear, the nose gear and main landing gear were calculated separately. The nose gear was estimated to be 60 pounds and the main landing gear was the remaining weight from the landing gear weight calculation. Table 11.2 shows the weights of each component as well as the payload, fuel, and “other”. Other is defined as all other minor components needed for the aircraft. These include things like avionics, navigation equipment, hydraulic equipment, and other small components. These were estimated to be evenly distributed throughout the entire aircraft.
Table 11.2: Component weightsComponent Weight
Fuselage 1855.50Wing 924.54
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Main Landing Gear 482.64Nose Landing Gear 60.00Engines 700.00other 1904.00Fuel Wing 2398.23Payload 1600.00Horizontal tail 509.0866Vertical tail 265.6097
The center of gravity for the entire aircraft is calculated using the standard one dimensional equation:
X cg=∑ Xn M n
∑M n
(11.1)
Each component is modeled as an evenly distributed load along the length of each component. With this assumption, the center of gravity for each component is easily determined. These values can be seen in Table 11.3 shown as the average percentage along the fuselage length. Also shown in Table 11.3 are the beginning and end locations of each component of the aircraft along with the overall calculated aircraft center of gravity. These as well are shown as a percentage of the fuselage length. The overall center of gravity is shown as the length back from the fuselage tip in feet.
Table 11.3: Component weight location and center of gravity
Load Type x/L Start x/L end x/L avgFuselage 0% 100% 0.5Wing 30% 55% 0.425Main LG 45% 45% 0.45Nose LG 5% 5% 0.05Engines 30% 45% 0.375other 0% 100% 0.5Fuel Fuselage 0% 100% 0.5Fuel Wing 35% 55% 0.45Payload 10% 60% 0.35H tail 80% 100% 0.9V tail 80% 100% 0.9Tail Lift 90% 90% 0.9
Xcg: 12.46 ft
Overall, the aircraft is stable with respect to the location of the center of gravity. With the location of the aerodynamic center of the wing located 13.5ft back from the nose of the aircraft, the aerodynamic center is behind the center of gravity and generates a static margin of 18%. This is well within the recommended static margin for stability.
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11.2 Wing Load AnalysisThe first step in calculating the shear and moment diagram is to find the load distribution across the wing. This load distribution has contributions from the lift generated by the wing, the landing gear, the engines, the structural weight of the wing, and the fuel that is stored within the wings. All of which are “negative” forces except that of the lifting force. The landing gear and the engines are treated as point loads, whereas the lift, fuel, and structural weights are distributed loads.
To find the lift distribution across the wing, Shrenck’s approximation is used, which averages an elliptical lift distribution with a trapezoidal lift distribution which is fairly accurate in real world modeling. The lift distribution for an elliptical wing is given by Equation 11.2, where the trapezoidal lift distribution is shown in Equation 11.3.
LE ( y )=4π
Lb √1−( y
b2 )
2
(11.2)
LT ( y )= 2(1+λ )
Lb [1−( y
b2 ) (1−λ )] (11.3)
In the above equations, L symbolizes the total load produced by the main wing and y is the half-span location where y = 0 signifies the root of the wing.
The total lift from the wing is found by first finding the lift, which is downforce, produced by the horizontal tail. This is found by Equation 11.4.
LT=W ¿
(xCG−xacw )(xacT
− xacw)
(11.4)
Then summing all the forces in the z-direction, the lift produced by the wing can be found through Equation 11.5.
LW=W ¿−LT (11.5)
The results from the combination of Equations 11.4 and 11.5 are shown in Table 11.4.
Table 11.4: Calculation of liftLT (lb) -1340LW (lb) 10860
With each contribution to the lift from the wing and the horizontal tail, both the elliptical and trapezoidal lift distributions can then be found and then averaged to provide a value for the lift. It is important to note that in the calculation for the lift and all the other distributed loads, the wing
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is broken into 21 sections to provide a rough integration of the loads over the wing. To increase the accuracy of the computations, the section count can be increased.
After the lift distribution is found, the next step is finding the structural distribution across the wing. This is found by Equation 11.6.
W structure ( y )=[2 W structure
(1+λ) ] [1− yb2
(1−λ)] (11.6)
The last distributed load across the wing is the fuels contribution. The fuel will be stored in between the main and rear spar in each wing. By using the chord length at each increment of the wing, after being discretized, the area between each of the spars can be found by estimating the area to be a rectangle. This is a two-dimensional calculation while looking at the “rib.” To make said area a volume, the subsequent ribs area between the main and rear spar will also be found, and then averaged to find an area that equally represents the two. By multiplying the average area between the two “ribs” by the distance between the segments, it provides a volume in which the fuel will be stored. Following this sequence of calculations up to the point between the eighth and ninth segment provides a volume of 20.27 ft3 which is just shy of the required volume of 22.86 ft3 per wing. To make up the remaining fuel storage, a bladder tank will be placed within the fuselage.
The engines weight, as well as the landing gear, are placed 7.98 feet from the root of the wing. As discussed this weight is treated as a point load within the spread sheet that calculates the total load distribution across the wing. After averaging the elliptical and trapezoidal lift, subtracting the fuel and structural load, and the two point loads from the engine and the landing gear; the following load distribution is found across the wing, Figure 11.1.
0 5 10 15 20 250
2
4
6
8
10
12
y (ft)
Load
(lb)
Figure 11.1: Total Wing Loading over the half-span
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It can easily be seen where the engines and landing gear are placed, y = 3.5 ft. It can also be seen where the fuel is placed, which is from the root to about 3 feet from the root. This is why the loading is slightly lower than that seen after the engine and landing gear. The entire spread sheet, which calculated the loads as well as the fuel volume can be seen in the Appendix.
After the total loading for the wing is found, the shear and moment values for each section can then be found. The shear diagram is simply the summation of the loads starting from the tip of the wing and working inwards. The moments at each segment can be found by multiplying each force in each segment by the distance to the segment being considered. Both the shear and moment values are then plotted to produce the shear and moment diagrams seen in Figures 11.2 and 11.3.
0 5 10 15 20 250.000
500.000
1000.000
1500.000
2000.000
2500.000
3000.000
3500.000
4000.000
y (ft)
Shea
r (lb
)
Figure 11.2: Shear Diagram for half-span
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0 5 10 15 20 250.000
5000.000
10000.000
15000.000
20000.000
25000.000
30000.000
35000.000
40000.000
y (ft)
Mom
ent(ft
-lb)
Figure 11.3: Moment Diagram for half-span
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11.3 Fuselage Load AnalysisWhen beginning the analysis of the fuselage structure, one must make sure to account for all weight sources and approximate them as point loads or distributed loads accordingly. These weights were determined analytically in a previous section. For this analysis the loads from the fuselage, wing structure, engines, extraneous entities, fuel, and payload were treated as distributed loads. The lift of the wing, lift of the tail, and weight of the landing gear were all treated as point loads at an interim point extrapolated from the 5% increments they fell between or near. In this analysis also, upward forces are treated as negative while downward forces have a positive sign convention.
Table 11.5: Component weights in (lbs)Component Weight (lbs)Fuselage 1855.50Payload 1600.00Wing 924.54Fuel 2398.23Tail 774.6963416main 482.64nose gear 60.00Engine 700.00Wing Lift Load 10860Tail Lift Load -1340Other 1428.00
Table 11.5 above shows the weights of each component.
In order to approximate the weight distribution of each component, the total weight of that respective component was spread across a predetermined number of stations in equal increments. The number of stations was determined form component placement,
Table 11.6: Starting and ending location for the weight of each componentLoad Type Load x/L Start x/L end x/L avgFuselage 1855.50 0% 100% 0.5Wing 924.54 30% 55% 0.425Main LG 482.64 45% 45% 0.45Nose LG 60.00 5% 5% 0.05Engines 700.00 30% 45% 0.375other 1428.00 0% 100% 0.5Fuel Fuselage 0.00 0% 100% 0.5Fuel Wing 2398.23 35% 55% 0.45Payload 1600.00 10% 60% 0.35
H tail 509.0866 80% 100% 0.9
V tail 265.6097 80% 100% 0.9
Tail Lift -1339.94 90% 90% 0.9
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The length of the fuselage was broken down into 20 increments in Table 11.6, each representing 5% of the total length of the aircraft, and loads were distributed accordingly. By summing the loads at each station one may easily produce the shear at a desired station. To find the moment at each station, one must add the moment of the previous station to the average of the shear at the desired station and the shear at the previous station, multiplied by 1.5 feet since this is representative of 5% of the fuselage length. However in the case of the point loads, a slight modification must be made to the moment calculation at the station immediately following the point load. The moment is found by adding the moment from the prior station to the average distance between the load location and following station multiplied by the load at that point.
Incorporating these approximations leads to a table as shown below which may also be viewed in the appendix,
Table 11.7: Excel sheet used to find the maximum shear and moment of the fuselagex/L x (ft) Wfuse (lbs) Wwing (lbs) Wlanding gear (lbs) Wengines (lbs) Wmisc (lbs) Wfuel (lbs) Wpayload (lbs) Wtail (lbs) L wing (lbs) L tail (lbs) Load (lbs) V (lbs) M (lb-ft)
0.000 0 0 0 0 0 0 0 0 0 0 0 0 0 00.0499 1.497 60 60 60 0
0.050 1.5 92.775 71.400 164.175 224.175 0.4260.100 3 92.775 71.400 164.175 388.350 459.8200.150 4.5 92.775 71.400 164.175 552.525 1165.4770.200 6 92.775 71.400 164.175 716.701 2117.3970.250 7.5 92.775 71.400 160.000 324.175 1040.876 3435.5790.300 9 92.775 154.090 233.333 71.400 160.000 711.599 1752.475 5530.5920.350 10.5 92.775 154.090 233.333 71.400 479.645 160.000 1191.244 2943.719 9052.7370.400 12 92.775 154.090 233.333 71.400 479.645 160.000 1191.244 4134.963 14361.748
0.4499 13.497 -10859.937 -10859.937 -6724.974 19670.7590.450 13.5 92.775 154.090 71.400 479.645 160.000 957.911 -5767.064 19654.4690.499 14.97 482.640 482.640 -5284.424 19560.7790.500 15 92.775 154.090 71.400 479.645 160.000 957.911 -4326.513 19488.6970.550 16.5 92.775 154.090 71.400 479.645 160.000 957.911 -3368.602 13717.3610.600 18 92.775 71.400 160.000 324.175 -3044.427 8907.5890.650 19.5 92.775 71.400 160.000 324.175 -2720.252 4584.0800.700 21 92.775 71.400 160.000 324.175 -2396.077 746.834
0.7257 21.7699998 1339.937 1339.937 -1056.139 -1811.3300.750 22.5 92.775 71.400 160.000 324.175 -731.964 -1322.2530.800 24 92.775 71.400 193.674 357.849 -374.115 -2151.8120.850 25.5 92.775 71.400 193.674 357.849 -16.266 -2444.5980.900 27 92.775 71.400 193.674 357.849 341.584 -2200.6090.950 28.5 92.775 71.400 193.674 357.849 699.433 -1419.8471.000 30 92.775 71.400 164.175 863.608 -247.567
As seen above in Table 11.7, the aircraft is has an excess of shear at the end of the fuselage. Further modifications will need to be made, and reduction of the weight of several components will need to be implemented. The moment however is small in comparison to the moments seen across the length of the fuselage. The aircraft will have a slight tendency to pitch down in its current state.
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Figure 11.4: Load distribution span wise across the fuselage
Figure 11.5: Shear distribution span wise across the fuselage
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Figure 11.6: Moment distribution span wise across the fuselage
Figures 11.4-11.6 are the produced plots for the aircraft in its current design status.
11.4 Fuselage DesignAfter the moment diagram for the fuselage was constructed, the design of the skin of the fuselage could be carried out. It is necessary to pick a thickness that would be suitable to withstand the maximum stresses that the aircraft could experience. Due to this, the maximum load factor was selected at a value of 5.8 and the maximum moment taken from the data was found to be 19670 foot pounds. With these values known, a material for the aircraft had to be selected. It was decided that due to its common use in aircraft that 2024-T3 Aluminum Alloy would be used for the skin of the fuselage. The minimum skin thickness was calculated using Equation 11.7 below.
(11.7)
Using the ultimate tensile strength for 2024-T3 found in Design of Aircraft, and with R being half of the largest distance in the fuselage, this yielded a skin thickness of approximately 0.0151 inches.
11.5 RecommendationsAll structural analyses considered, the team could predict the span-wise loading, shear, and moment on the wing, and the load, shear, and moment that the fuselage would experience in flight, through usage of a refined weight analysis. These calculations also allowed the design to pinpoint the center of gravity for the entire aircraft. It is important that care was taken in these calculations as they dictate the maximum loads that the aircraft will experience in flight. Taking into consideration these maximum loads and moments, the selection of 2024-T3 Aluminum
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Alloy was selected to be used for the fuselage due to its strength properties and common usage on similar aircraft of that type. 12 Stability and Control
Within this section, the longitudinal and lateral aircraft dynamics are calculated, plotted, and evaluated. Upon evaluations the aircraft must be open loop stable to provide a comfortable, and enjoyable aircraft to fly and be a passenger on.
12.1 Longitudinal StabilityIn the determination of the longitudinal stability of the aircraft various previously calculated parameters are needed. Table 12.1 displays the parameters that will be needed in the longitudinal stability. Along with these previously calculated variables, the downwash dε/dα must be found. This is determined via Figure 11.3 in Corke. In using this figure, taper ratio, the distance from the wing to the tail aerodynamic centers divided by the half-span of the aircraft, r, and finally the height of the horizontal tail divided by the half-span of the aircraft, m.
Table 12.1: Aircraft parameters.AR 8.0b (ft) 42.6
λ 0.4
iwing 1.4
SHT (ft2) 126.1
Sref (ft2) 226.7
mac (ft) 5.7
Vht 0.9
lht (ft) 9.3
Vstall (knots) 82.67
r 0.44H 2.00m 0.09dε/dα 0.45
Once these parameters are determined, the span-wise positions of the horizontal tail, main wing, and center of gravity must be found from previous calculations. These are displayed in Table 12.2, along with the non-dimensional span-wise positions described by Equation 12.1 with n being the position being described, and being the mean aerodynamic chord of the wing.
(12.1)
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Table 12.2: Span-wise positionsXcg (ft) 13.5
Xacwing(ft) 13.5
XacHT (ft) 22.8
Xbarcg 2.36
Xbaracwing 2.35
XbarHT 3.97
Figure 12.1: Visualization of the aerodynamic center and the center of gravity.
After all of the previously calculated parameters are tabulated, the stability analysis of the longitudinal aircraft dynamics can be performed.
First, the calculations that do not depend on angle of attack, such as the slope of the coefficient of lift and moment coefficient for the aircraft, are calculated and placed in a table. Equations 12.2-12.5 calculate these variables.
(12.2)
(12.3)
(12.4)
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(12.5)
Recall that static margin, S.M., must be positive in order to have longitudinal stability. Table 12.3 displays the calculated variables using the previously mentioned equations. Shown below, S.M., is indeed positive so longitudinal stability is achieved.
Table 12.3: Stability calculationsCLα_wing 0.086
CLα_HT 0.066
dCLair/dα 0.0654
dCM/dα -0.0326
xbarnp 16.94266192
S.M. 14.59
Now, varying angle of attack, the lift coefficient for the aircraft, and well as the moment coefficient of the aircraft can be determined for specific angles of attack. These are then used to determine the tail angle of incidence, iht, and the velocity of the aircraft. Equations 12.6-12.10 are used to determine the previously mentioned calculations.
(12.6)
(12.7)
(12.8)
(12.9)
(12.10)
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Figures 12.2 and 12.3 show the varying angle of attack versus the change in the moment coefficient of the aircraft. As seen, the slope of the moment curve is negative, this is characteristic of a longitudinally stable aircraft.
Figure 12.2: Decrease of moment coefficient with increase of angle of attack at iht=0°
Figure 12.3: Decrease of moment coefficient with increase of angle of attack at iht=5°
Analyzing these two plots, it is clear that with increase of horizontal tail incidence, the angle of attack at which the moment coefficient becomes zero increases.
Figure 12.4 displays the lift coefficient as it changes with respect to horizontal tail incidence.
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0.000 0.200 0.400 0.600 0.800 1.000 1.200 1.400 1.600 1.800 2.0000.000
5.000
10.000
15.000
20.000
25.000
30.000
CL
iht
Figure 12.4: Lift coefficient versus horizontal tail incidence.
As shown, with increasing lift coefficient, the incidence angle of the horizontal tail must also increase in order to produce the lift coefficient need for the aircraft to maintain level flight.
Figure 12.5 depicts the relation between aircraft velocity and horizontal tail incidence. As seen in the figure, as the aircraft increases to its designated cruise velocity, the tail incidence angle can be decreased. Once the aircraft starts to slow to its stall speed, the pilot must increase the tail incidence angle in order to hold steady level flight.
Figure 12.5: Relationship between velocity and tail incidence angle.
The excel table used to create Figures 12.2-12.5 can be seen in Appendix O.
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12.2 Lateral StabilityThe lateral motion of the aircraft is defined as the rolling motion about the fuselage longitudinal axis. The aircraft can witness a wind come in that is off the centerline of the aircraft. This wing would be known as a sideslip and the resulting angle that the wind comes in is the sideslip angle, β. The notation for the lateral stability is defined using the symbol C lβ. For ta aircraft, the right wing tip should rotate up to counter a positive side slip angle which would in turn cause C lβ to be less than zero. The total lateral stability of the aircraft is generally cut into section based on the wing section, vertical stabilizer, and wing-fuselage combination, shown in Equation 12.11.
(12.11)
Even further so, the contribution by the main wing is divided into three more subsections based on the wing position, sweep angle of the wing, and the dihedral of the wing. This is presented in Equation 12.12.
(12.12)
Taking each of these subdivisions into consideration, an estimate of the lateral stability of the aircraft can be determined via means of this equation. The wing mounting position to the fuselage has an effect with a high wing being good towards the lateral stability, a mid-wing having a neutral effect to the lateral stability, and a low wing being the less advantageous of the two. The lateral stability is also effected by the sweep angle of the wing as well. In the presence of a sideslip angle, the incoming velocity would be higher on one wing than the other causing a moment around the center of gravity of the aircraft. Lastly, the dihedral angle of the wing can have an effect of the lateral stability, with a positive dihedral angle increasing the lateral stability. In terms of the design aircraft, the dihedral of the wing will counteract the low wing positioning causing the lateral stability to be stable while in flight.
Seeing as how the lateral stability for an aircraft is a difficult parameter to calculate, it is usually taken as an approximation that the lateral stability is equal to the opposite of the directional stability. This is shown in Equation 12.13 and as thus, the lateral stability and directional values will be presented after the directional section.
(12.13)
12.3 Directional StabilityThe directional motion of an aircraft is a rotation about its vertical axis. Here, the directional moment about the center of gravity is defined as positive in a clockwise direction. A sideslip angle will cause the aircraft to what to yaw in a certain direction which is then counteracted by the lateral lift producing a moment around the center of gravity of the aircraft. The directional stability is denoted by the symbol Cnβ and is divided into three subsections as well shown in Equation 12.14
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(12.14)
The F, W, and VS in the above equation represent the fuselage, wing, and vertical stabilizer, respectively. In the terms of the directional stability, the aircraft should rotate in such a manner that the sideslip angle is reduced making Cnβ a positive value.
For the vertical stabilizer contribution, Equation 12.15 shows the calculation for this parameter.
(12.15)
Where is the vertical tail volume coefficient presented in Equation 12.16.
(12.16)
is the three dimensional lift curve slope for the vertical tail, and the quantity is the influence of the wing and fuselage on the vertical tail, and is shown in Equation 12.17.
(12.17)
The value for the wing’s contribution to the directional stability can be expressed in Equation 12.18.
(12.18)
The effect due to the fuselage was calculated using Equation 12.19.
(12.19)
Where the volume of the fuselage, (VOL)F was found using a solidworks model.
Using the above equations, the effect to directional stability could be calculated and in turn the l. These values are shown below in Table 12.4.
Table 12.4: Lateral and Direction StabilityCn VTβ 0.140763Cn Wβ 0.000672Cnβ F -0.05600
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According to Design of Aircraft, both of these values fall in the range to make the aircraft be stable.
12.4 Rudder SizingThe Rudder sizing is determined off two worst case scenarios. The first is considered the single engine condition, and the second is considering a cross wind with a sideslip of 11.5 degrees during takeoff and landing. Both of these cases assume that the rudder is capable of a maximum defection of 20 degrees.
First considering the engine out scenario in equilibrium, the value can be determined using Equation 12.20.
(12.20)
The secondary scenario considered is the cross-wind scenario where sideslip angle is considered to be 11.5 degrees. Equation 12.21 shows the equilibrium state for the cross wing section.
(12.21)
Using this value, the change in zero lift angle due to the rudder deflection can be calculated using Equation 12.22.
(12.22)
Using the aforementioned equations, the value for the zero lift angle change due to the rudder deflection was found to be -0.48. Using this value, and figure 11.9 in Design of Aircraft it was found that the size of the rudder was about 18% of the total vertical tail which comes out to be 11.84 square feet.
Table 12.5 below shows the stability derivatives along with the Rudder size below.
Table 12.5: Stability Derivatives and Rudder SizeCnβ 0.0854Clβ -0.0854SR (ft2) 11.84
Figure 12.5 below shows a drawing of the rudder attached to the vertical tail.
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Figure 12.6: Drawing of Rudder
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13 Engineering Conclusions and 3 View DrawingsUpon calculation of all the data throughout the design process the design team was capable
of reaching the ultimate goal in the design of this aircraft requested by Beechcraft Inc. Table 13.1 shows the pertinent design parameters that were calculated throughout the design process.
Table 13.1: Pertinent Design Parameters
Structure Factor 0.58 Fuel Req (gal) 358 Pinstall (HP) 2440
AR 8 bVT (ft) 8.51 CD0 0.0226
W/S (psf) 42 SVT (ft2) 65.79 STO (ft) 1026
TOGW (lbs) 9520 X ac VT (ft) 21 S clear obstacle (ft) 1374
bw (ft) 42.58 ΛLE VT (°) 57.5 S Land w/ flaps (ft) 1782
S (ft2) 226.67 bHT (ft) 19.45 ΔCL max 1.095m.a.c. (ft) 5.73 HT Airfoil NACA 64-004 Wing Lift (lb) 10078
ΛLE Wing (°) 0 SHT (ft2) 126.1 Tail Lift (lbs) -558.3
Xac W (ft) 13.5 Xac HT (ft) 22.77 Vmax Wing (lb) 3067.8
Wing Airfoil NACA-2412 ΛLE HT (°) 29.8 Mmax Wing (lb-ft) 33163.3
Dfuse (ft) 5.25 Xcg (ft) 13.5 Vmax fuse (lb) 5943.3
lfuse (ft) 30 VT Airfoil NACA 64-004 Mmax fuse (lb-ft) 19670.8
As well as the pertinent design parameters, below in Figure 13.1 is a three-view drawing showcasing the aircraft and its overall dimensions. This figure can also be viewed in the Appendix section of the report.
Figure 13.1: 3 view drawing for final aircraft design.
84
Completion of the aircraft has the team rather pleased with the overall outcome of the aircraft and its design features. One feature the team feels could have been improved upon was the horizontal and vertical stabilizers. The empennage design of the aircraft called for a larger horizontal and vertical tail section due to the minimization of the fuselage in order to reach the target cruise speed of 320 knots, however; this minuet feature does not hinder the overall performance of the aircraft, and the design team is confident in the success of the aircraft’s final design. Without any further ado allow the Left βrothers to introduce the Gyrfalcon 536.
85
ReferencesAngel Aircraft Corporation. AAC Brochure. Orange City: Angel Aircraft Corporation, n.d. Print.
"Angel Aircraft Corporation Photo Gallery2." Angel Aircraft Corporation Photo Gallery2. Angel Aircraft Corporation, 2008. Web. 29 Aug. 2016.
Graphiq. "AAC Angel Private Turboprop-driven Propeller Plane." Axlegeeks. Graphiq, 2016. Web. 29 Aug. 2016.
Mark, Robert P. "King Air C90 Ditching Still under Investigation." Aviation International News. AINOnline, 7 May 2012. Web. 29 Aug. 2016.
Textron Aviation. King Air C90GTx. N.p.: Textron Aviation, 2014. Print.
Corke, Thomas C. Design of Aircraft. Upper Saddle River, NJ: Prentice Hall, 2003. Print.
Abbott, Ira H., and Albert E. Von. Doenhoff. Theory of Wing Sections: Including a Summary of Airfoil Data. New York, NY: Dover Publ., 1982. Print.
Gjenvick, Paul K. "The Piper Cheyenne II XL - Specifications, Diagrams and Photo (1981)." Piper Cheyenne II XL. N.p., n.d. Web. 19 Sept. 2016.
"King Air C90GTx." King Air C90GTx. Textron Aviation, n.d. Web. 19 Sept. 2016.
Goebel, Greg. "Yet58_1b." Flickr. Yahoo!, n.d. Web. 17 Oct. 2016.
Image of Leading edge flaps. Digital image. N.p., n.d. Web. http://users.skynet.be/spotterfreak/flightcontrols2.html
Image of Trailing edge flaps. Digital image. N.p., n.d. Web. http://zoomaviation.com/programs/charts/flap_leading_edge_devices.png
86
Appendix A – Request of ProposalSpreadsheet showing request of proposal (RFP)
87
Range (NM) 1000
Holding (contingency) fuel 30 minutesReserve fuel 45 minutes
Design Cruise Speed (knots) 300 @ 25,00ft
Payload
6 passengers arranged in luxury seeting (36" seat pitch)
plus crew (pilot and copilot)
FAR Tafeoff Distance (ft) 2,000FAR Landing Distance (ft) 2,000
88
Appendix B – Gross Takeoff WeightSpreadsheet used in determining the gross takeoff weight
89
Cruise Altitude (ft) 25000Range (NM) 1000# of Passengers 6# of Crew 2Holding (min) 30Reserve (min) 45Vcr @ 25,000 feet (knots) 320
Structural Factor 0.58AR 8W/S (psf) 42CD0 0.0250Engine sfc (lbs/hr/HP) 0.57Prop Effi ciency 0.85ρ @ 25,000 Feet (sl/ft3) 0.001066Oswald's Effi ciency Factor 0.85
(L/D)max 14.62
CL (L/D)max 0.7308
CL act 0.2932
WCruise (lbf) 8317.46
VHold/Reserve (knots) 145
(L/D)Cruise 10.10Bregeut Range Factor 4911.19Bregeut Endurance Factor 60.04Avg. Passengers w/ bags (lbf) 200Total Payload Weight (lbf) 1600Iterated Final TOGW (lbs) 9520
Mission Requirements
Inpute Values
Calculations
MAE 475 Flight Vehcle Design
90
Flight Phase Fuel Fraction Used IterationTOGW 9520Start-Up & TO 0.98 190 9330Climb and Accel to Cruise 0.98 187 9143Cruise (Bregeut) 1684 7459Descent and Land 0.975 186 7272Reserve (Breguet Endurance) 91 7181Holding 60Total Fuel Weight 2398Total Fuel and Payload Weight 3998
Wt available for strucutre 5522Wt required for structure 5522Difference 0
91
Appendix C – Weight AnalysisMatlab code used for takeoff weight sensitivity analysis is displayed below.
92
clc
clear
data=xlsread('\desktop\MAE 475 Takeoff Estimate');
%Mission Requirements
cruise=data(1,1);
pass=data(3,1);
crew=data(4,1);
holding=data(5,1); %minutes
reserve=data(6,1); %minutes
V_cr=data(7,1); %@25,000ft Knots
% Input Values
S=data(9,1);
Wing_load=data(11,1);
sfc=data(13,1);
eff=data(14,1);
rho=data(15,1); %@25,000ft
os_eff=data(16,1);
%Variation Values
%
%
for Range=[500 1000 1500];
for AR=[5 7 9];
for C_Do=[0.0180 0.0210 0.0240 0.0270];
%Calculations
LD_max=0.5*sqrt((pi()*AR*os_eff)/C_Do);
C_L_LD_Max=sqrt(pi()*AR*os_eff*C_Do);
C_Lact=(2*Wing_load)/(rho*(V_cr*1.62)^2);
V_hold=145;
LD_cruise=LD_max*((2*C_Lact/C_L_LD_Max)/(1+(C_Lact/C_L_LD_Max)^2));
93
Bre_range=326*eff*LD_cruise*(1/sfc);
Bre_end=(1/sfc)*550*(LD_max)*(1/(V_hold*1.62));
Avg_pass=200;
total_payload=Avg_pass*(pass+crew);
diff=1;
while diff > 0.2
TOGW=randi([2000 28000]);
start=TOGW*0.98;
climb=start*0.98;
u1=TOGW-start;
u2=start-climb;
cruise_used=((1-(1/(exp((Range/Bre_range))))))*climb;
cruise=climb-cruise_used;
land=cruise*0.975;
land_used=cruise-land;
reserve_used=(((sfc*(45/60))/(LD_max))*land*(V_hold*1.62))/(550);
reserve_wgt=land-reserve_used;
hold_used=(1-(1/(exp(0.5/Bre_end))))*reserve_wgt;
total_fuel=(u1+u2+land_used+cruise_used+reserve_used+hold_used);
fuel_payload=total_fuel+total_payload;
Wt_ava=TOGW-fuel_payload;
WT_req=TOGW*S;
diff=Wt_ava-WT_req;
diff=abs(diff);
end
fprintf('TOGW for Range of %iNM ,AR of %i, and C_Do of %.4f = %ilbs',Range,AR,C_Do,TOGW);
fprintf('\n');
end
fprintf('\n');
end
fprintf('\n');
end
94
Appendix DThis appendix shows the spreadsheet used for determining the values in the report
95
Design Parameters AirfoilData Viscous DragVcruise (knots) 320 Name NACA
63-212Cdo 0.0035 V
(ft/sec)540.8
Vcruise (ft/sec) 540.8 Clmax 1.35 rle 0.0024 q (lb/ft^2)
155.88
M 0.48 Cla 0.1096 Cl minD 0 Re 1E10^7Meff 0.48 a.c. 0.35 (t/c)max 35% CF 0.002927S(ft2) 226.67 αoL (deg) -1.160 t/c 12% Swet(ft2) 462.27
AR 8 Sweep Angles Atmospheric Conditions
F 1.44
ɅLE(deg) 0 ɅLE 0 ν (cruise) 0.00030178 Q 1
W/S(lb/ft2) begin cruise
40.34 Ʌ1/4 chord -3.44 q(lb/ft2) 155.88
W/S(lb/ft2) after cruise
32.91 Ʌt/c max -4.82 ρ (sl/ft3) 0.001066
ε(deg) -2 ɅTE -13.54
ᴦ(deg) 3.5 Calculations
ʎ 0.35 b(ft) 42.58 C Ltrim 0.26
Drag Summary cr (ft) 7.89 CL (begin
cruise)
0.259
CDO Wing 0.00859 ct (ft) 2.76 CL (end cruise) 0.211Cdi(begin cruise) 0.00313 m.a.c. (ft) 5.73 CL (max) 1.350
Cdi(end cruise) 0.00209 iw(deg) 1.86 CLα 0.0856Induced Drag(begin cruise) (lb)
110.75 k 0.05 CLo 0.0993
Induced Drag(end cruise) (lb)
73.70 e 0.85 CD 0.012
Zero Lift Drag (lb) 303.67 Δαol 0.84 L/D 22.062Total Drag (lb) 488.12 αstall (deg) 14.6 Vstall
(ft/sec)236.76
96
AirfoilDataName NACA
63-212Cdo 0.0035
Clmax 1.35 rle 0.0024Cla 0.1096 Cl minD 0a.c. 0.35 (t/c)max 35%αoL (deg) -1.160 t/c 12%
Sweep Angles Atmospheric Conditions
ɅLE 0 ν (cruise)
0.00030178
Ʌ1/4 chord -3.44 q(lb/ft2) 155.88
Ʌt/c max -4.82 ρ (sl/ft3)
0.001066
ɅTE -13.54
Calculations
b(ft) 42.58 C Ltrim 0.26
cr (ft) 7.89 CL (begin
cruise)
0.259
ct (ft) 2.76 CL (end
cruise)
0.211
m.a.c. (ft) 5.73 CL (max) 1.350
iw(deg) 1.86 CLα 0.0856k 0.05 CLo 0.0993e 0.85 CD 0.012Δαol 0.84 L/D 22.062αstall (deg) 14.6 Vstall
(ft/sec)236.76
97
Appendix E – Drag CalculationsExcel spreadsheet showing the drag force and zero lift drag coefficient calculations.
98
99
Dimension Data
1 gal0.133681
ft^3Fuel Tank Type
FuselageW
inghcruise (ft)
25000D
fuse5.25
r(o)2.625
spec Vol, gas6.7
lbs/galDiscrete
100%-
V (knots)320.00
l/d5.714285714
Total Fuel used (lbs)2398.227
Bladder 83%
77%V (ft/sec)
540.80L (ft)
30Total Fuel required (gal)
357.9443Integral
93%85%
q (lbs/ft2)
155.884S (ft
2)226.67
Total Fuel required (ft^3)47.85035
ρ (sl/ft3)
0.00107Shape
Ojibe Cross Section, Sears-HaackVolum
e Required (ft^3)56.295
µ (sl ft/sec)3.22E-07
F1.480
ν (ft2/sec)0.000302
Q1
Low wing, well-filleted
x/Ldx
r(x)/r(o)r(x)
x (ft)xm
idpoint (ft)D
mid (ft)
Pmid (ft)
Awet (ft
2)Rex m
idCf
Drag (lb)0.00
00
00.0
00
00
00
00.10
30.464758
1.2199897543.0
1.82.43998
7.66522.996
32233110.003549
12.720640.20
30.715542
1.8782971016.0
5.43.756594
11.80235.405
96699340.002957
16.317230.30
30.877424
2.3032377629.0
94.606476
14.47243.415
161165560.002727
18.458190.40
30.969847
2.54584953612.0
12.65.091699
15.99647.988
225631790.00259
19.372810.50
31
2.62515.0
16.25.25
16.49349.480
290098010.002493
19.230050.60
30.969847
2.54584953618.0
19.85.091699
15.99647.988
354564240.00242
18.099820.70
30.877424
2.30323776221.0
23.44.606476
14.47243.415
419030460.002361
15.975860.80
30.715542
1.87829710124.0
273.756594
11.80235.405
483496690.002312
12.758240.90
30.464758
1.21998975427.0
30.62.43998
7.66522.996
547962910.00227
8.1373811.00
30
030.0
34.20
0.0000.000
612429140.002234
0Total
141.0702lbs
Cdo0.003992461
Fuselage DesignVolum
e EffectivenessDesign Param
eters
Viscuous Drag Calc
Appendix F – Empennage DesignThis section contains the spreadsheet used in the calculation the vertical and horizontal tail.
100
101
b (ft
)42.58
hcruise (ft
)25000
Wing Placem
ent45%
m.a.c. (ft
)5.73
V (ft/sec)
540.8X
acW13.5
Sr (ft
2)226.67
ρ (slugs/ft3)
0.001066X
ac VT (ft)
21.0029.19
Ʌ1/4 (deg)
-3.4442ν (ft
2/sec)0.000302
Xac HT (ft
)22.77
29.64
t/c12%
q (lbf/ft2)
155.88365λ
0.35M
0.48X
acW-0.53789
CVT
0.07N
ame
NACA 64-004
CHT
0.9N
ame
NACA 64-004
lVT (ft)
10.27Clm
ax0.8
Cf
0.002792lHT (ft
)9.27
Clmax
0.8C
f0.002871
ΛLE (deg)
35Clalpha (/deg)
0.11RE
13848898Λ
LE (deg)40
Clalpha (/deg)0.11
RE11609803
t/c8%
t/cmax
40%S
wet (ft
2)132.8048
t/c8%
t/c max
40%S
wet (ft
2)254.5433
λ0.4
a.c.0.26
F1.207603
λ0.4
a.c.0.26
F1.300171
αoL (deg)
0Q
1α
oL (deg)0
Q1
SVT (ft
2)65.79
CDo VT
0.0034S
HT (ft2)
126.10C
Do HT0.0037
b (ft)
8.51Λ
LE (deg)57.50
D (lbf)
69.80865b (ft
)19.45
ΛLE (deg)
29.80D
(lbf)148.1205
cr (ft
)11.05
Λ1/4 (deg)
49.72c
r (ft)
9.26Λ
1/4 (deg)23.26
ct (ft
)4.42
ΛTE (deg)
0.64c
t (ft)
3.70Λ
TE (deg)0.07
ARVT
1.10Λ
t/c max (deg)
43.42AR
HT3.00
Λt/c m
ax (deg)18.99
Xac VT (ft
)2.86
Xac HT (ft
)2.39
β0.86
β0.76
CLα
0.0283CL
α0.0589
m.a.c (ft
)8.21
m.a.c (ft
)6.88
Sweep Angles
Calculations
Sweep Angles
Air PropertiesM
ain Wing
Horizontal TailVertical Tail
Viscous DragViscous Drag
Calculations
Xac Locations
Appendix G – Power RequirementsSpreadsheet used to calculate the power requirements for the design.
102
Wing 303.7 Preqd 25,000 ft (HP) 883.66
Fuselage 178.7 Pshp reqd 25,000 ft (HP) 1039.60
Horizontal Tail 166.1 Pshp SSL (HP) 2769.21
Vertical Tail 126.1 Preqd climb (HP) 2065.35
Nacelle 33.1 Pinstall 2769.21Induced Wing 92.2
Total 899.9
Component CD
Wing 0.00859 ROC (FPM) 250Fuselage 0.005056 ηP 0.85
Horizontal Tail 0.006944 Pavail (HP) 1500
Vertical Tail 0.007331 Preqd climb 1202.9Nacelle 0.000939
Induced Wing 0.00261Total 0.03146978
SFC at Full Power [lb/(HP*hr)] 0.61Max Env. Diameter (in) 20.9Max Env. Length (in) 55
q 155.4780664
Zero
Lift
Ze
ro L
ift
103
Appendix H – Engine PerformanceFull spreadsheet data for calculation of engine performance parameters.
104
105
SSLV(knots)
W (lbs)
L (lbs)Sref (ft
2)h (ft
2)e
ARη
propC
D0ρ
qC
LC
DiD (lbs)
Vcr (fps)
Preq
Pshp req
Pshp avail
Pexcess
ROC (fpm)
γ (deg)60
9520#NUM
!226.67
00.85
80.85
0.0250.002377
12.188313.445873
0.5558271604.666
101.268295.4569
347.59633000
2704.54319374.9919
#NUM!
709520
#NUM!
226.670
0.858
0.850.025
0.00237716.58965
2.5316620.300022
1222.204118.146
262.5427308.8737
30002737.4573
9489.0853#NUM
!80
9520#NUM
!226.67
00.85
80.85
0.0250.002377
21.668111.938303
0.175867986.5614
135.024242.199
284.943000
2757.8019559.6042
#NUM!
909520
#NUM!
226.670
0.858
0.850.025
0.00237727.42371
1.5314990.109793
837.8911151.902
231.4133272.251
30002768.5867
9596.9916#NUM
!100
95203010.777
226.670
0.858
0.850.025
0.00237733.85643
1.2405140.072035
744.671168.78
228.5192268.8462
30002771.4808
9607.023771.56322
1109520
4839.258226.67
00.85
80.85
0.0250.002377
40.966281.025218
0.049201689.0177
185.658232.5848
273.62923000
2767.41529592.9308
59.44765120
95205880.672
226.670
0.858
0.850.025
0.00237748.75326
0.8614680.034739
660.1719202.536
243.1065286.0077
30002756.8935
9556.458551.85035
1309520
6591.781226.67
00.85
80.85
0.0250.002377
57.217370.734032
0.025222651.346
219.414259.8444
305.69933000
2740.15569498.4384
46.1785140
95207115.287
226.670
0.858
0.850.025
0.00237766.3586
0.6329150.018751
658.0861236.292
282.7282332.6214
30002717.2718
9419.114641.63399
1509520
7518.307226.67
00.85
80.85
0.0250.002377
76.176970.55134
0.014229677.3714
253.17311.8002
366.82383000
2688.19989318.3395
37.83896160
95207838.287
226.670
0.858
0.850.025
0.00237786.67246
0.4845760.010992
707.0946270.048
347.1809408.4481
30002652.8191
9195.696634.57849
1709520
8098.256226.67
00.85
80.85
0.0250.002377
97.845080.429244
0.008625745.7491
286.926389.0451
457.70013000
2610.95499050.5789
31.71678180
95208313.304
226.670
0.858
0.850.025
0.002377109.6948
0.3828750.006862
792.2351303.804
437.6076514.8325
30002562.3924
8882.242429.16191
1909520
8493.778226.67
00.85
80.85
0.0250.002377
122.22170.343633
0.005528845.7343
320.682493.1123
580.13213000
2506.88778689.8419
26.84853200
95208647.02
226.670
0.858
0.850.025
0.002377135.4257
0.3101290.004502
905.6275337.56
555.8247653.9115
30002444.1753
8472.456324.72847
2109520
8778.376226.67
00.85
80.85
0.0250.002377
149.30690.281296
0.003704971.4395
354.438626.0274
736.50283000
2373.97268229.1067
22.7652220
95208891.827
226.670
0.858
0.850.025
0.002377163.8651
0.2563050.003075
1042.801371.316
704.0156828.2536
30002295.9844
7958.769520.93033
2309520
8990.386226.67
00.85
80.85
0.0250.002377
179.10050.234502
0.0025741119.42
388.194790.0946
929.5233000
2209.90547660.3864
19.20141240
95209076.364
226.670
0.858
0.850.025
0.002377195.013
0.2153670.002171
1201.065405.072
884.57781040.68
30002115.4222
7332.871117.56038
2509520
9151.556226.67
00.85
80.85
0.0250.002377
211.60270.198482
0.0018441287.55
421.95987.7849
1162.13000
2012.21516975.1154
15.99248260
95209217.367
226.670
0.858
0.850.025
0.002377228.8695
0.1835080.001576
1378.723438.828
1100.0411294.166
30001899.9592
6585.993114.48554
2709520
9274.903226.67
00.85
80.85
0.0250.002377
246.81340.170167
0.0013551474.462
455.7061221.675
1437.2643000
1778.32546164.3634
13.0294280
95209325.039
226.670
0.858
0.850.025
0.002377265.4344
0.1582290.001172
1574.663472.584
1353.0191591.787
30001646.9812
5709.073611.61547
2909520
9368.468226.67
00.85
80.85
0.0250.002377
284.73260.147505
0.0010181679.241
489.4621494.409
1758.1283000
1505.59125218.9611
10.23645300
95209405.736
226.670
0.858
0.850.025
0.002377304.7079
0.1378350.000889
1788.127506.34
1646.1821936.685
30001353.8176
4692.85518.886049
3109520
9437.274226.67
00.85
80.85
0.0250.002377
325.36030.129086
0.000781901.26
523.2181808.679
2127.8583000
1191.32064129.5778
7.558835320
95209463.415
226.670
0.858
0.850.025
0.002377346.6898
0.1211440.000687
2018.59540.096
1982.2412332.048
30001017.7588
3527.94556.250056
3309520
9484.415226.67
00.85
80.85
0.0250.002377
368.69650.113913
0.0006072140.075
556.9742167.211
2549.663000
832.789332886.7697
4.955531340
95209500.461
226.670
0.858
0.850.025
0.002377391.3803
0.1073110.000539
2265.676573.852
2363.9322781.096
3000636.06801
2204.85763.671549
3509520
9511.686226.67
00.85
80.85
0.0250.002377
414.74130.101266
0.000482395.363
590.732572.75
3026.7653000
427.249711481.0127
2.394791
106
25000 ftV(knots)
W (lbs)
L (lbs)S
ref (ft2)
h (ft2)
eAR
ηprop
CD0
ρq
CL
CDi
D (lbs)V
cr (fps)P
req P
shp req P
shp availP
excessROC (fpm
)γ (deg)
609520
9140.348226.67
250000.85
80.85
0.0250.001066
5.4660267.683715
2.7636543455.098
101.268636.1652
748.42961126.24
490.074971698.7893
16.2355270
95209133.491
226.6725000
0.858
0.850.025
0.0010667.439868
5.6451781.491752
2557.842118.146
549.4524646.4146
1126.24576.78773
1999.369216.38246
809520
9156.249226.67
250000.85
80.85
0.0250.001066
9.7173794.322089
0.8744371981.135
135.024486.3651
572.19431126.24
639.875042218.0542
15.8896390
95209189.594
226.6725000
0.858
0.850.025
0.00106612.29856
3.4149840.545907
1591.525151.902
439.5562517.1249
1126.24686.68398
2380.312115.13935
1009520
9225.055226.67
250000.85
80.85
0.0250.001066
15.18342.766137
0.358171318.725
168.78404.6807
476.0951126.24
721.559442501.2039
14.29938110
95209259.08
226.6725000
0.858
0.850.025
0.00106618.37192
2.2860640.244635
1122.856185.658
379.0314445.9193
1126.24747.20872
2590.114213.44528
1209520
9290.341226.67
250000.85
80.85
0.0250.001066
21.86411.920929
0.172728979.9292
202.536360.8563
424.53681126.24
765.383892653.1164
12.61065130
95209318.502
226.6725000
0.858
0.850.025
0.00106625.65995
1.6367680.125405
874.8076219.414
348.991410.5776
1126.24777.24919
2694.246111.80929
1409520
9343.648226.67
250000.85
80.85
0.0250.001066
29.759471.411295
0.093234797.5601
236.292342.6492
403.11671126.24
783.590932716.2291
11.04542150
95209366.03
226.6725000
0.858
0.850.025
0.00106634.16266
1.2293940.07075
741.451253.17
341.2966401.5254
1126.24784.94353
2720.917710.31869
1609520
9385.943226.67
250000.85
80.85
0.0250.001066
38.869521.080522
0.054652701.7812
270.048344.572
405.37881126.24
781.668152709.564
9.626648170
95209403.677
226.6725000
0.858
0.850.025
0.00106643.88004
0.9571410.042884
675.1916286.926
352.2364414.3958
1126.24774.00374
2682.99628.965932
1809520
9419.493226.67
250000.85
80.85
0.0250.001066
49.194230.853746
0.034119659.2296
303.804364.1392
428.39911126.24
762.100932641.7364
8.332964190
95209433.62
226.6725000
0.858
0.850.025
0.00106654.81209
0.7662430.027484
652.0702320.682
380.1949447.2881
1126.24746.04527
2586.08137.724232
2009520
9446.25226.67
250000.85
80.85
0.0250.001066
60.733620.691534
0.022386652.3333
337.56400.3666
471.01961126.24
725.873542516.1583
7.136444210
95209457.545
226.6725000
0.858
0.850.025
0.00106666.95882
0.6272420.018417
658.9591354.438
424.6548499.5939
1126.24701.58532
2431.96596.566588
2209520
9467.641226.67
250000.85
80.85
0.0250.001066
73.487680.571516
0.01529671.1232
371.316453.0887
533.04551126.24
673.151482333.4033
6.011941230
95209476.647
226.6725000
0.858
0.850.025
0.00106680.32021
0.5228990.012799
688.1762388.194
485.7198571.435
1126.24640.5204
2220.29135.470065
2409520
9484.655226.67
250000.85
80.85
0.0250.001066
87.456410.480232
0.010796709.6013
405.072522.6175
614.84411126.24
603.622652092.3894
4.938779250
95209491.736
226.6725000
0.858
0.850.025
0.00106694.89628
0.4425820.009169
734.983421.95
563.8656663.3713
1126.24562.37456
1949.40764.416143
2609520
9497.95226.67
250000.85
80.85
0.0250.001066
102.63980.409192
0.007838763.9839
438.828609.5592
717.12841126.24
516.680981791.016
3.900426270
95209503.341
226.6725000
0.858
0.850.025
0.001066110.687
0.3794430.00674
796.3282455.706
659.8028776.2386
1126.24466.43737
1616.85223.390083
2809520
9507.945226.67
250000.85
80.85
0.0250.001066
119.03790.352824
0.005827831.7881
472.584714.7087
840.83371126.24
411.531491426.5272
2.883738290
95209511.787
226.6725000
0.858
0.850.025
0.001066127.6924
0.328910.005064
870.1748489.462
774.3954911.0534
1126.24351.84474
1219.62992.380156
3009520
9514.885226.67
250000.85
80.85
0.0250.001066
136.65060.307349
0.004422911.33
506.34838.9869
987.04351126.24
287.25322995.73068
1.87823310
95209517.251
226.6725000
0.858
0.850.025
0.001066145.9125
0.2878390.003878
955.1208523.218
908.61161068.955
1126.24217.62854
754.384651.376966
3209520
9518.889226.67
250000.85
80.85
0.0250.001066
155.47810.270131
0.0034161001.435
540.096983.4016
1156.9431126.24
142.8386495.13379
0.875467330
95209519.798
226.6725000
0.858
0.850.025
0.001066165.3473
0.2540070.00302
1050.176556.974
1063.4921251.167
1126.2462.748071
217.509070.372921
3409520
9519.975226.67
250000.85
80.85
0.0250.001066
175.52020.239285
0.002681101.262
573.8521149.021
1351.791126.24
-22.78106-78.96797
-0.13141350
95209519.409
226.6725000
0.858
0.850.025
0.001066185.9967
0.2258070.002387
1154.624590.73
1240.1291458.976
1126.24-113.8892
-394.7839-0.63819
107
31000 ftV(knots)
W (lbs)
L (lbs)Sref (ft
2)h (ft
2)e
ARη
propC
D0ρ
qC
LC
DiD (lbs)
Vcr (fps)
Preq
Pshp req
Pshp avail
Pexcess
ROC (fpm)
γ (deg)60
95209508.163
226.6731000
0.858
0.850.025
0.0008574.394357
9.5575734.275988
4284.08101.268
788.8003928.0004
876.18387.382711
302.902262.85747
709520
9475.852226.67
310000.85
80.85
0.0250.000857
5.9812087.02189
2.3080723163.086
118.146679.4654
799.371876.183
196.71766681.89946
5.52007280
95209452.824
226.6731000
0.858
0.850.025
0.0008577.812189
5.3761351.352949
2440.057135.024
599.0296704.7407
876.183277.1534
960.720816.810528
909520
9441.058226.67
310000.85
80.85
0.0250.000857
9.8873024.24781
0.844641948.997
151.902538.2846
633.276876.183
337.898451171.2867
7.383696100
95209437.218
226.6731000
0.858
0.850.025
0.00085712.20655
3.4407260.554168
1602.475168.78
491.756578.5365
876.183384.427
1332.57267.561408
1109520
9438.274226.67
310000.85
80.85
0.0250.000857
14.769922.843575
0.3785041350.891
185.658456.0067
536.4785876.183
420.17631456.4935
7.512968120
95209442.158
226.6731000
0.858
0.850.025
0.00085717.57743
2.3893930.267249
1164.401202.536
428.7876504.456
876.183447.3954
1550.84547.33202
1309520
9447.567226.67
310000.85
80.85
0.0250.000857
20.629062.035933
0.194031024.18
219.414408.5809
480.6834876.183
467.602151620.8898
7.072353140
95209453.704
226.6731000
0.858
0.850.025
0.00085723.92483
1.7554730.144254
917.874236.292
394.3387463.9279
876.183481.84432
1670.25876.765749
1509520
9460.088226.67
310000.85
80.85
0.0250.000857
27.464731.529212
0.109465837.1042
253.17385.3267
453.3255876.183
490.856341701.4978
6.431361160
95209466.434
226.6731000
0.858
0.850.025
0.00085731.24876
1.3440340.084559
776.0258270.048
381.0258448.2657
876.183495.15718
1716.40626.080875
1709520
9472.575226.67
310000.85
80.85
0.0250.000857
35.276921.190563
0.066351730.4605
286.926381.0693
448.3168876.183
495.113731716.2556
5.721441180
95209478.413
226.6731000
0.858
0.850.025
0.00085739.54921
1.0619530.05279
697.3575303.804
385.2453.1764
876.183490.98304
1701.9375.357404
1909520
9483.899226.67
310000.85
80.85
0.0250.000857
44.065630.95311
0.042523674.4469
320.682393.2418
462.6374876.183
482.941251674.0611
4.991345200
95209489.005
226.6731000
0.858
0.850.025
0.00085748.82618
0.8601820.034635
660.0118337.56
405.0792476.5638
876.183471.10379
1633.02784.624722
2109520
9493.72226.67
310000.85
80.85
0.0250.000857
53.830870.78021
0.028495652.7341
354.438420.6432
494.8743876.183
455.539831579.0771
4.258281220
95209498.041
226.6731000
0.858
0.850.025
0.00085759.07968
0.7108940.023657
651.5881371.316
439.9002517.5296
876.183436.28283
1512.32493.892306
2309520
9501.971226.67
310000.85
80.85
0.0250.000857
64.572630.650421
0.019803655.7665
388.194462.8447
544.5232876.183
413.338271432.7902
3.526789240
95209505.511
226.6731000
0.858
0.850.025
0.00085770.3097
0.5973480.016703
664.6261405.072
489.4935575.8747
876.183386.6895
1340.41533.161542
2509520
9508.665226.67
310000.85
80.85
0.0250.000857
76.290910.550516
0.014187677.6502
421.95519.8809
611.6246876.183
356.302131235.0809
2.796264260
95209511.435
226.6731000
0.858
0.850.025
0.00085782.51625
0.5089830.012127
694.4191438.828
554.0555651.83
876.183322.12749
1116.61842.430592
2709520
9513.823226.67
310000.85
80.85
0.0250.000857
88.985720.471979
0.010428714.5896
455.706592.0778
696.5621876.183
284.10526984.81865
2.064129280
95209515.827
226.6731000
0.858
0.850.025
0.00085795.69932
0.4388680.009016
737.8786472.584
634.0175745.9029
876.183242.16551
839.439281.696466
2909520
9517.446226.67
310000.85
80.85
0.0250.000857
102.65710.409123
0.007835764.051
489.462679.9526
799.9442876.183
196.23042680.2105
1.327194300
95209518.675
226.6731000
0.858
0.850.025
0.000857109.8589
0.3823030.006842
792.9101506.34
729.9675858.7853
876.183146.21555
506.839620.955916
3109520
9519.508226.67
310000.85
80.85
0.0250.000857
117.30490.358036
0.006001824.2905
523.218784.1521
922.5319876.183
92.030924319.01476
0.582247320
95209519.939
226.6731000
0.858
0.850.025
0.000857124.995
0.3360080.005285
858.0523540.096
842.6011991.2954
876.18333.581889
116.407810.205818
3309520
9519.956226.67
310000.85
80.85
0.0250.000857
132.92930.315953
0.004673894.0763
556.974905.4132
1065.192876.183
-29.23017-101.3231
-0.17372340
95209519.551
226.6731000
0.858
0.850.025
0.000857141.1077
0.2976410.004147
932.2607573.852
972.69031144.341
876.183-96.50724
-334.5314-0.55669
3509520
9518.71226.67
310000.85
80.85
0.0250.000857
149.53020.280876
0.003693972.5179
590.731044.537
1228.867876.183
-168.3542-583.5808
-0.94342
Appendix I - TakeoffValues used in the numerical integration of the takeoff performance spreadsheet.
108
HP 2769 AR 8.00 ΔCDflap 0
W (lbs) 9520 e 0.85 ΔCDgear 0.0215
Merit 0.8 CLα 0.09 CDo 0.0216
Dprop (ft) 8 iw 1.36 CLmax 1.8
ρ 0.002377 α0L -1.66 Δt 0.5
Aprop (ft2) 50.26548246 δflaps 0 μ3.62E-
07
Sref (ft2) 226.67 ηprop 0.85
W/S 42.00
W/P 3.43779954
Vstall 140.12 ft/sec 95.53 mph
1.2*Vstall 168.14 ft/sec114.6
4 mph
Takeoff Integration
Comments t Vx Vy V (fps)
Sx Sy (ft) γ Θ Tact Tx
0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 7079.2 7079.2 0.5 11.3 0.0 11.3 2.8 0.0 0.0 0.0 7079.2 7079.2 1 22.7 0.0 22.7 11.3 0.0 0.0 0.0 7079.2 7079.2 1.5 34.0 0.0 34.0 25.5 0.0 0.0 0.0 7079.2 7079.2 2 45.3 0.0 45.3 45.3 0.0 0.0 0.0 7079.2 7079.2 2.5 56.7 0.0 56.7 70.8 0.0 0.0 0.0 7079.2 7079.2 3 68.0 0.0 68.0 102.0 0.0 0.0 0.0 7079.2 7079.2 3.5 79.3 0.0 79.3 138.8 0.0 0.0 0.0 7079.2 7079.2 4 90.7 0.0 90.7 181.3 0.0 0.0 0.0 7079.2 7079.2 4.5 102.1 0.0 102.1 229.5 0.0 0.0 0.0 7079.2 7079.2 5 113.4 0.1 113.4 283.4 0.0 0.0 0.0 7079.2 7079.2 5.5 124.8 0.1 124.8 343.0 0.0 0.0 0.0 7079.2 7079.2 6 136.2 0.1 136.2 408.2 0.0 0.0 0.0 7079.2 7079.2 6.5 147.7 0.1 147.7 479.2 0.0 0.0 0.0 7079.2 7079.2 7 159.1 0.1 159.1 555.9 0.0 0.0 0.0 7079.2 7079.21.2 Vstall 7.5 170.5 0.1 170.5 638.3 0.0 0.0 3.0 7079.2 7069.5 8 182.1 0.1 182.1 726.5 0.0 0.0 6.0 7079.2 7040.4
109
8.5 193.8 0.1 193.8 820.4 0.0 0.0 9.0 7079.2 6992.0 9 205.7 2.6 205.7 920.3 0.0 0.7 12.0 7079.2 6924.5 9.5 217.4 11.2 217.7 1026.1 3.5 3.0 15.0 6996.5 6758.1 10 227.8 24.3 229.1 1137.4 12.3 6.1 15.0 6648.9 6422.3 10.5 236.3 34.2 238.7 1253.4 27.0 8.2 15.0 6380.0 6162.635ft obs 11 243.7 41.6 247.2 1373.4 45.9 9.7 15.0 6161.5 5951.6 11.5 250.4 47.1 254.8 1496.9 68.1 10.
7 15.0 5977.0 5773.3
12 256.7 51.4 261.8 1623.7 92.7 11.3
15.0 5816.7 5618.5
12.5 262.7 55.0 268.4 1753.6 119.3 11.8
15.0 5674.8 5481.4
13 268.4 58.0 274.6 1886.3 147.6 12.2
15.0 5547.2 5358.2
13.5 273.8 60.7 280.4 2021.9 177.2 12.5
15.0 5431.5 5246.4
14 278.9 63.1 286.0 2160.0 208.2 12.8
15.0 5325.7 5144.2
14.5 283.9 65.4 291.3 2300.7 240.3 13.0
15.0 5228.4 5050.2
15 288.6 67.5 296.4 2443.9 273.5 13.2
15.0 5138.5 4963.4
15.5 293.2 69.6 301.3 2589.3 307.8 13.3
15.0 5055.0 4882.7
16 297.5 71.5 306.0 2737.0 343.1 13.5
15.0 4977.2 4807.6
16.5 301.8 73.3 310.5 2886.8 379.3 13.7
15.0 4904.5 4737.4
17 305.8 75.0 314.9 3038.7 416.4 13.8
15.0 4836.4 4671.6
17.5 309.8 76.7 319.1 3192.6 454.3 13.9
15.0 4772.4 4609.8
18 313.6 78.3 323.2 3348.5 493.0 14.0
15.0 4712.1 4551.5
Comments t Vx Vy V (fps)
Sx Sy (ft) γ Θ Tact Tx
18.5 317.3 79.8 327.2 3506.2 532.6 14.1
15.0 4655.1 4496.5
19 320.9 81.3 331.0 3665.7 572.9 14.2
15.0 4601.3 4444.5
19.5 324.3 82.7 334.7 3827.0 613.9 14.3
15.0 4550.2 4395.2
20 327.7 84.1 338.3 3990.0 655.6 14.4
15.0 4501.7 4348.3
20.5 331.0 85.4 341.8 4154.7 698.0 14. 15.0 4455.6 4303.8
110
5 21 334.2 86.7 345.2 4321.0 741.0 14.
5 15.0 4411.7 4261.4
21.5 337.3 88.0 348.5 4488.9 784.7 14.6
15.0 4369.8 4220.9
22 340.3 89.2 351.8 4658.2 829.0 14.7
15.0 4329.8 4182.3
22.5 343.2 90.3 354.9 4829.1 873.8 14.7
15.0 4291.6 4145.3
23 346.1 91.5 358.0 5001.4 919.3 14.8
15.0 4254.9 4110.0
23.5 348.9 92.6 360.9 5175.2 965.3 14.9
15.0 4219.8 4076.0
24 351.6 93.6 363.8 5350.3 1011.9 14.9
15.0 4186.1 4043.5
24.5 354.2 94.7 366.7 5526.7 1059.0 15.0
15.0 4153.8 4012.2
25 356.8 95.7 369.4 5704.5 1106.6 15.0
15.0 4122.7 3982.2
25.5 359.4 96.7 372.1 5883.5 1154.6 15.1
15.0 4092.7 3953.3
26 361.8 97.7 374.8 6063.8 1203.2 15.1
15.0 4063.9 3925.4
26.5 364.3 98.6 377.4 6245.3 1252.3 15.1
15.0 4036.1 3898.6
27 366.6 99.5 379.9 6428.1 1301.8 15.2
15.0 4009.3 3872.7
27.5 368.9 100.4 382.3 6611.9 1351.8 15.2
15.0 3983.5 3847.8
28 371.2 101.3 384.8 6797.0 1402.2 15.3
15.0 3958.5 3823.6
28.5 373.4 102.1 387.1 6983.1 1453.1 15.3
15.0 3934.4 3800.3
29 375.6 103.0 389.4 7170.4 1504.3 15.3
15.0 3911.0 3777.7
29.5 377.7 103.8 391.7 7358.7 1556.0 15.4
15.0 3888.4 3755.9
30 379.8 104.6 393.9 7548.1 1608.1 15.4
15.0 3866.5 3734.8
30.5 381.8 105.3 396.1 7738.5 1660.6 15.4
15.0 3845.3 3714.3
31 383.8 106.1 398.2 7929.9 1713.4 15.5
15.0 3824.7 3694.4
31.5 385.8 106.8 400.3 8122.3 1766.7 15.5
15.0 3804.8 3675.2
32 387.7 107.6 402.3 8315.7 1820.3 15. 15.0 3785.5 3656.5111
5 32.5 389.6 108.3 404.4 8510.0 1874.2 15.
5 15.0 3766.7 3638.3
33 391.4 109.0 406.3 8705.2 1928.5 15.6
15.0 3748.4 3620.7
33.5 393.3 109.7 408.3 8901.4 1983.2 15.6
15.0 3730.7 3603.6
34 395.0 110.3 410.1 9098.5 2038.2 15.6
15.0 3713.4 3586.9
34.5 396.8 111.0 412.0 9296.4 2093.5 15.6
15.0 3696.7 3570.7
35 398.5 111.6 413.8 9495.2 2149.2 15.6
15.0 3680.4 3555.0
35.5 400.2 112.3 415.6 9694.9 2205.1 15.7
15.0 3664.5 3539.6
36 401.8 112.9 417.4 9895.4 2261.4 15.7
15.0 3649.0 3524.7
36.5 403.5 113.5 419.1 10096.7 2318.0 15.7
15.0 3634.0 3510.2
37 405.1 114.1 420.8 10298.9 2374.9 15.7
15.0 3619.3 3496.0
37.5 406.6 114.7 422.5 10501.8 2432.1 15.7
15.0 3605.0 3482.2
Comments t Vx Vy V (fps)
Sx Sy (ft) γ Θ Tact Tx
38 408.2 115.2 424.1 10705.5 2489.6 15.8
15.0 3591.1 3468.7
38.5 409.7 115.8 425.7 10909.9 2547.4 15.8
15.0 3577.5 3455.6
39 411.2 116.4 427.3 11115.2 2605.4 15.8
15.0 3564.2 3442.7
39.5 412.6 116.9 428.9 11321.1 2663.7 15.8
15.0 3551.2 3430.2
40 414.1 117.4 430.4 11527.8 2722.3 15.8
15.0 3538.6 3418.0
40.5 415.5 118.0 431.9 11735.2 2781.2 15.9
15.0 3526.3 3406.1
41 416.9 118.5 433.4 11943.3 2840.3 15.9
15.0 3514.2 3394.5
41.5 418.3 119.0 434.9 12152.1 2899.6 15.9
15.0 3502.4 3383.1
42 419.6 119.5 436.3 12361.6 2959.3 15.9
15.0 3490.9 3372.0
42.5 420.9 120.0 437.7 12571.7 3019.1 15.9
15.0 3479.7 3361.1
43 422.2 120.5 439.1 12782.5 3079.3 15. 15.0 3468.7 3350.5112
9 43.5 423.5 120.9 440.5 12993.9 3139.6 15.
9 15.0 3457.9 3340.1
44 424.8 121.4 441.8 13206.0 3200.2 15.9
15.0 3447.4 3329.9
44.5 426.0 121.9 443.1 13418.7 3261.0 16.0
15.0 3437.1 3320.0
45 427.3 122.3 444.4 13632.1 3322.1 16.0
15.0 3427.0 3310.2
45.5 428.5 122.8 445.7 13846.0 3383.3 16.0
15.0 3417.1 3300.7
46 429.7 123.2 447.0 14060.5 3444.8 16.0
15.0 3407.5 3291.4
46.5 430.8 123.6 448.2 14275.6 3506.5 16.0
15.0 3398.0 3282.2
47 432.0 124.0 449.4 14491.4 3568.4 16.0
15.0 3388.8 3273.3
47.5 433.1 124.5 450.7 14707.6 3630.6 16.0
15.0 3379.7 3264.5
48 434.2 124.9 451.8 14924.5 3692.9 16.0
15.0 3370.8 3255.9
48.5 435.3 125.3 453.0 15141.9 3755.4 16.1
15.0 3362.1 3247.5
49 436.4 125.7 454.2 15359.8 3818.2 16.1
15.0 3353.5 3239.3
49.5 437.5 126.1 455.3 15578.3 3881.1 16.1
15.0 3345.2 3231.2
50 438.6 126.5 456.4 15797.3 3944.2 16.1
15.0 3337.0 3223.3
113
Ty αaircraft αeff CL q Lw Lwx Lwy CD D Dx Dy
0.0 1.4 3.0 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.00.0 1.3 3.0 0.3 0.2 8.9 0.0 8.9 1.8 63.8 0.0 63.80.0 1.3 3.0 0.3 0.6 35.5 0.0 35.5 2.3 321.5 0.1 321.50.0 1.3 3.0 0.3 1.4 79.8 0.0 79.8 2.3 716.7 0.3 716.70.0 1.3 3.0 0.3 2.4 142.0 0.1 142.0 0.5 278.4 0.1 278.40.0 1.3 3.0 0.3 3.8 221.9 0.1 221.9 0.0 2.7 0.0 2.70.0 1.3 3.0 0.3 5.5 319.6 0.1 319.6 0.0 3.8 0.0 3.80.0 1.3 3.0 0.3 7.5 435.2 0.2 435.2 0.0 5.2 0.0 5.20.0 1.3 3.0 0.3 9.8 568.8 0.3 568.8 0.0 6.8 0.0 6.80.0 1.3 3.0 0.3 12.4 720.2 0.3 720.2 0.0 8.7 0.0 8.70.0 1.3 3.0 0.3 15.3 889.7 0.4 889.7 0.0 10.7 0.0 10.70.0 1.3 3.0 0.3 18.5 1077.3 0.5 1077.3 0.0 12.9 0.0 12.90.0 1.3 3.0 0.3 22.1 1283.0 0.6 1283.0 0.0 15.4 0.0 15.40.0 1.3 3.0 0.3 25.9 1507.0 0.7 1507.0 0.0 18.1 0.0 18.10.0 1.3 3.0 0.3 30.1 1749.4 0.8 1749.4 0.0 21.0 0.0 21.0370.5 4.3 6.0 0.5 34.6 4021.3 1.8 4021.3 0.0 96.6 0.0 96.6740.0 7.3 9.0 0.8 39.4 6879.5 3.0 6879.5 0.0 248.0 0.1 248.01107.4 10.3 12.0 1.0 44.7 10392.1 4.6 10392.1 0.0 499.5 0.2 499.51471.8 12.6 14.3 1.2 50.3 13954.5 175.5 13953.4 0.1 799.5 10.1 799.41810.8 13.4 15.1 1.3 56.3 16462.1 848.7 16440.2 0.1 993.7 51.2 992.31720.9 10.3 11.9 1.0 62.4 14433.8 1531.8 14352.2 0.0 689.9 73.2 686.01651.3 8.1 9.8 0.8 67.7 12847.9 1842.4 12715.1 0.0 503.3 72.2 498.11594.7 6.7 8.3 0.7 72.6 11745.8 1976.1 11578.3 0.0 392.3 66.0 386.71547.0 5.7 7.4 0.6 77.2 11032.3 2039.6 10842.1 0.0 325.7 60.2 320.11505.5 5.0 6.7 0.6 81.5 10587.2 2079.1 10381.0 0.0 284.1 55.8 278.51468.7 4.5 6.2 0.5 85.6 10311.3 2111.2 10092.8 0.0 256.5 52.5 251.01435.7 4.2 5.8 0.5 89.6 10136.5 2140.6 9907.9 0.0 236.8 50.0 231.51405.8 3.9 5.5 0.5 93.5 10020.5 2168.1 9783.1 0.0 221.9 48.0 216.61378.4 3.6 5.3 0.5 97.2 9938.4 2193.8 9693.3 0.0 209.8 46.3 204.71353.2 3.4 5.0 0.4 100.9 9876.5 2217.6 9624.3 0.0 199.7 44.8 194.61329.9 3.2 4.9 0.4 104.4 9827.0 2239.3 9568.5 0.0 191.0 43.5 186.01308.3 3.0 4.7 0.4 107.9 9785.8 2259.2 9521.5 0.0 183.3 42.3 178.31288.2 2.9 4.5 0.4 111.3 9750.5 2277.4 9480.8 0.0 176.4 41.2 171.51269.4 2.7 4.4 0.4 114.6 9719.6 2294.1 9445.0 0.0 170.2 40.2 165.41251.8 2.6 4.2 0.4 117.9 9692.3 2309.4 9413.1 0.0 164.6 39.2 159.91235.2 2.5 4.1 0.4 121.1 9667.8 2323.5 9384.5 0.0 159.5 38.3 154.81219.6 2.3 4.0 0.3 124.2 9645.8 2336.6 9358.5 0.0 154.7 37.5 150.11204.8 2.2 3.9 0.3 127.2 9625.8 2348.8 9334.8 0.0 150.4 36.7 145.91190.9 2.1 3.8 0.3 130.2 9607.5 2360.1 9313.2 0.0 146.4 36.0 141.91177.7 2.1 3.7 0.3 133.2 9590.9 2370.7 9293.3 0.0 142.7 35.3 138.2Ty αaircraft αeff CL q Lw Lwx Lwy CD D Dx Dy
114
1165.1 2.0 3.6 0.3 136.0 9575.5 2380.5 9274.9 0.0 139.2 34.6 134.81153.2 1.9 3.5 0.3 138.9 9561.4 2389.8 9257.9 0.0 135.9 34.0 131.61141.8 1.8 3.5 0.3 141.7 9548.3 2398.6 9242.1 0.0 132.9 33.4 128.71131.0 1.7 3.4 0.3 144.4 9536.1 2406.8 9227.4 0.0 130.1 32.8 125.91120.6 1.7 3.3 0.3 147.1 9524.8 2414.5 9213.7 0.0 127.4 32.3 123.21110.7 1.6 3.3 0.3 149.7 9514.2 2421.9 9200.8 0.0 124.9 31.8 120.81101.3 1.6 3.2 0.3 152.3 9504.3 2428.8 9188.7 0.0 122.5 31.3 118.41092.2 1.5 3.2 0.3 154.8 9495.1 2435.4 9177.4 0.0 120.3 30.8 116.21083.5 1.4 3.1 0.3 157.3 9486.3 2441.7 9166.7 0.0 118.1 30.4 114.11075.1 1.4 3.1 0.3 159.8 9478.1 2447.7 9156.6 0.0 116.1 30.0 112.21067.0 1.3 3.0 0.3 162.2 9470.4 2453.3 9147.1 0.0 114.2 29.6 110.31059.3 1.3 3.0 0.3 164.6 9463.1 2458.8 9138.1 0.0 112.4 29.2 108.51051.8 1.3 2.9 0.2 166.9 9456.2 2463.9 9129.5 0.0 110.6 28.8 106.81044.6 1.2 2.9 0.2 169.2 9449.6 2468.9 9121.4 0.0 109.0 28.5 105.21037.7 1.2 2.8 0.2 171.5 9443.4 2473.6 9113.7 0.0 107.4 28.1 103.61031.0 1.1 2.8 0.2 173.7 9437.5 2478.1 9106.3 0.0 105.9 27.8 102.11024.5 1.1 2.8 0.2 175.9 9431.8 2482.5 9099.3 0.0 104.4 27.5 100.71018.3 1.1 2.7 0.2 178.1 9426.5 2486.6 9092.6 0.0 103.0 27.2 99.41012.2 1.0 2.7 0.2 180.2 9421.3 2490.7 9086.2 0.0 101.7 26.9 98.11006.4 1.0 2.7 0.2 182.3 9416.5 2494.5 9080.0 0.0 100.4 26.6 96.81000.7 1.0 2.6 0.2 184.4 9411.8 2498.2 9074.2 0.0 99.2 26.3 95.6995.2 0.9 2.6 0.2 186.5 9407.3 2501.8 9068.6 0.0 98.0 26.1 94.5989.9 0.9 2.6 0.2 188.5 9403.0 2505.2 9063.2 0.0 96.9 25.8 93.4984.8 0.9 2.5 0.2 190.4 9398.9 2508.5 9058.0 0.0 95.8 25.6 92.3979.7 0.9 2.5 0.2 192.4 9395.0 2511.7 9053.0 0.0 94.7 25.3 91.3974.9 0.8 2.5 0.2 194.3 9391.2 2514.8 9048.2 0.0 93.7 25.1 90.3970.2 0.8 2.5 0.2 196.2 9387.6 2517.8 9043.6 0.0 92.7 24.9 89.4965.6 0.8 2.4 0.2 198.1 9384.1 2520.7 9039.2 0.0 91.8 24.7 88.4961.1 0.8 2.4 0.2 199.9 9380.7 2523.4 9034.9 0.0 90.9 24.5 87.5956.8 0.7 2.4 0.2 201.7 9377.5 2526.1 9030.8 0.0 90.0 24.2 86.7952.6 0.7 2.4 0.2 203.5 9374.4 2528.7 9026.8 0.0 89.2 24.1 85.9948.4 0.7 2.4 0.2 205.3 9371.3 2531.3 9023.0 0.0 88.3 23.9 85.1944.4 0.7 2.3 0.2 207.1 9368.4 2533.7 9019.3 0.0 87.5 23.7 84.3940.5 0.7 2.3 0.2 208.8 9365.6 2536.1 9015.7 0.0 86.8 23.5 83.5936.7 0.6 2.3 0.2 210.5 9362.9 2538.4 9012.3 0.0 86.0 23.3 82.8933.0 0.6 2.3 0.2 212.1 9360.3 2540.6 9008.9 0.0 85.3 23.1 82.1929.4 0.6 2.3 0.2 213.8 9357.8 2542.8 9005.7 0.0 84.6 23.0 81.4925.9 0.6 2.2 0.2 215.4 9355.3 2544.9 9002.5 0.0 83.9 22.8 80.7922.5 0.6 2.2 0.2 217.0 9352.9 2546.9 8999.5 0.0 83.2 22.7 80.1919.1 0.5 2.2 0.2 218.6 9350.6 2548.9 8996.5 0.0 82.6 22.5 79.5Ty αaircraft αeff CL q Lw Lwx Lwy CD D Dx Dy
915.9 0.5 2.2 0.2 220.2 9348.4 2550.9 8993.6 0.0 82.0 22.4 78.9
115
912.7 0.5 2.2 0.2 221.7 9346.2 2552.7 8990.8 0.0 81.4 22.2 78.3909.5 0.5 2.2 0.2 223.2 9344.1 2554.6 8988.1 0.0 80.8 22.1 77.7906.5 0.5 2.1 0.2 224.8 9342.1 2556.4 8985.5 0.0 80.2 21.9 77.1903.5 0.5 2.1 0.2 226.2 9340.1 2558.1 8983.0 0.0 79.6 21.8 76.6900.6 0.5 2.1 0.2 227.7 9338.2 2559.8 8980.5 0.0 79.1 21.7 76.1897.8 0.4 2.1 0.2 229.1 9336.3 2561.4 8978.1 0.0 78.6 21.6 75.5895.0 0.4 2.1 0.2 230.6 9334.5 2563.0 8975.7 0.0 78.0 21.4 75.0892.2 0.4 2.1 0.2 232.0 9332.7 2564.6 8973.5 0.0 77.5 21.3 74.6889.6 0.4 2.1 0.2 233.4 9331.0 2566.1 8971.2 0.0 77.0 21.2 74.1887.0 0.4 2.0 0.2 234.8 9329.3 2567.6 8969.1 0.0 76.6 21.1 73.6884.4 0.4 2.0 0.2 236.1 9327.7 2569.1 8967.0 0.0 76.1 21.0 73.2881.9 0.4 2.0 0.2 237.4 9326.1 2570.5 8964.9 0.0 75.6 20.8 72.7879.5 0.4 2.0 0.2 238.8 9324.6 2571.9 8962.9 0.0 75.2 20.7 72.3877.1 0.3 2.0 0.2 240.1 9323.1 2573.2 8961.0 0.0 74.8 20.6 71.9874.7 0.3 2.0 0.2 241.4 9321.6 2574.5 8959.1 0.0 74.3 20.5 71.5872.4 0.3 2.0 0.2 242.6 9320.2 2575.8 8957.2 0.0 73.9 20.4 71.1870.2 0.3 2.0 0.2 243.9 9318.8 2577.1 8955.4 0.0 73.5 20.3 70.7868.0 0.3 2.0 0.2 245.1 9317.4 2578.3 8953.6 0.0 73.1 20.2 70.3865.8 0.3 1.9 0.2 246.4 9316.1 2579.5 8951.9 0.0 72.7 20.1 69.9863.7 0.3 1.9 0.2 247.6 9314.8 2580.7 8950.2 0.0 72.4 20.1 69.5
116
Ff ax ay
380.8 22.7 0.0380.4 22.7 0.0379.4 22.7 0.0377.6 22.7 0.0375.1 22.7 0.0371.9 22.7 0.0368.0 22.7 0.0363.4 22.7 0.0358.0 22.7 0.0352.0 22.8 0.0345.2 22.8 0.0337.7 22.8 0.0329.5 22.8 0.0320.5 22.9 0.0310.8 22.9 0.0219.9 23.2 0.0105.6 23.4 0.0-34.9 23.8 5.0-177.4 23.4 17.3-277.7 20.8 26.2-196.6 17.0 19.8-133.1 14.8 14.7-89.0 13.5 11.0-60.5 12.6 8.6-42.7 11.9 7.1-31.7 11.3 6.1-24.7 10.8 5.4-20.0 10.3 4.9-16.7 9.9 4.6-14.3 9.5 4.3-12.3 9.1 4.0-10.6 8.8 3.8-9.2 8.4 3.6-8.0 8.2 3.5-6.9 7.9 3.3-5.9 7.6 3.2-5.0 7.4 3.1-4.2 7.2 3.0-3.5 6.9 2.8-2.8 6.7 2.7Ff ax ay
117
-2.2 6.5 2.7-1.7 6.4 2.6-1.1 6.2 2.5-0.6 6.0 2.4-0.2 5.9 2.30.2 5.7 2.30.6 5.6 2.21.0 5.4 2.11.3 5.3 2.11.7 5.2 2.02.0 5.1 2.02.3 4.9 1.92.6 4.8 1.92.8 4.7 1.83.1 4.6 1.83.3 4.5 1.73.5 4.4 1.73.7 4.3 1.73.9 4.2 1.64.1 4.2 1.64.3 4.1 1.64.5 4.0 1.54.7 3.9 1.54.8 3.8 1.55.0 3.8 1.45.2 3.7 1.45.3 3.6 1.45.4 3.6 1.35.6 3.5 1.35.7 3.4 1.35.8 3.4 1.35.9 3.3 1.26.1 3.3 1.26.2 3.2 1.26.3 3.1 1.26.4 3.1 1.16.5 3.0 1.16.6 3.0 1.16.7 2.9 1.16.8 2.9 1.1Ff ax ay
6.9 2.8 1.17.0 2.8 1.0
118
7.0 2.7 1.07.1 2.7 1.07.2 2.7 1.07.3 2.6 1.07.3 2.6 0.97.4 2.5 0.97.5 2.5 0.97.6 2.5 0.97.6 2.4 0.97.7 2.4 0.97.8 2.3 0.97.8 2.3 0.87.9 2.3 0.87.9 2.2 0.88.0 2.2 0.88.0 2.2 0.88.1 2.1 0.88.2 2.1 0.88.2 2.1 0.8
119
Appendix J - LandingLanding Calculations
120
Landing PerformanceWlanding (lbf) 7272 γapproach (rads) 0.052359878 Dbraking
(lbf)1385.086
W/S (lbf/ft2) 32.083 RTR (ft) 4391.654326 LTD (lbf) 402.671Vstall (ft/sec) 133.264 HTR (ft) 6.018609624 Ff(lbf) 4121.701523V50 feet (ft/sec) 173.244 CL TD 1.216 ax (ft/sec2) -26.166VTD (ft/sec) 153.254 AReff 26.101 Sbraking (ft) 897.602q50 feet (lbf/ft2) 35.671 CDo 0.0250 Sapproach (ft) 839.215qTD (lbf/ft2) 27.914 CDi, braking 0.0212 Sflare (ft) 229.841μL Dry 0.6 CDo flaps 0.08300 SFR (ft) 459.762μL Wet 0.4 CDo LG 0.08969 SL total (ft) 2426.420
121
Appendix K – Enhanced LiftSpreadsheet of enhanced lift calculations
122
Trailing Edge Calculations Origin Leading Edge Device Origin
λ 0.35 Type Fixed Slot C1 0.48 Fig 9.8 ΔClmax 0.2 Table 9.1
AR 8.00 ΔCLmax
0.09791349
Comparative Value 2.703
Therefoe High AR Wing
ΛLE 0 TOTAL
CLmax/Clmax 0.9 Fig 9.9 ΔCLmax 1.095Clmax 1.52 CLmax 1.368 Eq 9.5Δy/c (%) 8.5 Fig 9.10Δy 0.487 Δ⍺CLmax 1.8 Fig 9.11
⍺s (deg) 16.13 Eq 9.6δflap (deg) 40 δf 10 40 50
Δ⍺s (deg) -2.8 Fig 9.18K1 (Fig 9.20) 2 2 2
(⍺s) flapped (deg) 13.33 Eq 9.10
k2 (Fig. 9.21) 0.0125 0.0875 0.12
c (ft) 5.73 ΔCD0
0.01223919
0.08567431
0.11749619
cf (ft) 2 cf/c 0.349 t/c 12% dCl / dδf (rad)-1 5.35 Fig 9.4(Clmax)flapped 3.74 ΔClmax 2.22 Eq 9.11bf (ft) 8
SWF
110.970259
SW 226.67 KΔ 0.919 Eq 9.12
ΔCLmax 0.997 Eq 9.9
123
124
Appendix L – Refined WeightRefined weight analysis
125
Load Type Load x/L Start x/L end x/L avg MFuselage 1855.50 0% 100% 0.5 927.751581 Aircraft CG 12.3Wing 924.54 30% 55% 0.425 392.930178Main LG 482.64 45% 45% 0.45 217.188Nose LG 60.00 5% 5% 0.05 3Engines 700.00 30% 45% 0.375 262.5 b (ft) 42.58other 1428.00 0% 100% 0.5 714 ʎ 0.35Fuel Fuselage 0.00 0% 100% 0.5 0 WTO 9520Fuel Wing 2398.23 35% 55% 0.45 1079.20206 AR 8.00Payload 1600.00 10% 60% 0.35 560 Croot (ft) 7.89
H tail 509.0866 80% 100% 0.9 458.177983 Ctip (ft) 2.76
V tail 265.6097 80% 100% 0.9 239.048725 Lfuse (ft) 30
Tail Lift -1339.94 90% 90% 0.9 -1205.94341 xacH (ft) 21.77
xacW (ft) 13.5X_cg_placement 12.3SM 21% Stable x/L 0.41062475
X_cg 12.3187426 LT -1340
LW 10860
Aircraft Data
Lift Calculations
126
Appendix M – Wing LoadingExcel sheet used to determine the wing loading of the aircraft.
127
128
V(shear)M
(mom
ent)
b (ft)
42.58station
y (ft)
y/(b/2)Lift
/unit spanLift/station
Lift/unit spanLift
/stationAverage
FuelEngine &
LGStructure
Total
ʎ0.35
10
0324.710
377.8173455.256
36608.736
WTO
95200.532
0.5320.025
345.466395.684
370.575-168.27282
-19.976182.3267
AR8.00
21.065
0.05324.304
365.5383272.929
33027.360Croot (ft
)7.89
1.5971.597
0.075344.600
382.612363.606
-157.42688-19.316
186.8633
Ctip ( ft)
2.763
2.1290.1
323.082353.259
3086.06629642.502
Lfuse (ft)
302.661
2.6610.125
342.861369.540
356.200-146.942239
-18.656190.6021
xacH (ft)
21.774
3.1940.15
321.036340.980
2895.46326458.567
xacW (ft)
13.53.726
3.7260.175
340.235356.467
348.351-136.818898
-17.996193.5365
delta y (ft)
1.0655
4.2580.2
318.149328.701
2701.92723479.106
delta y /2 (ft)
0.532294564.791
4.7910.225
336.702343.395
340.049-127.056856
-17.336195.6559
65.323
0.25314.399
316.4222506.271
22591.8075.855
5.8550.275
332.233330.323
331.278-117.656115
-16.676196.9460
LT-1339.94
76.388
0.3309.753
304.1432309.325
18143.495LW
108606.920
6.9200.325
326.789317.251
322.020-108.616673
-16.016197.3873
87.452
0.35304.172
291.8642111.938
15790.0817.984
7.9840.375
320.321304.179
312.250-99.9385308
-591.32-15.356
-394.36499
8.5170.4
297.601279.585
2506.30313331.817
9.0499.049
0.425312.764
291.107301.935
-14.696287.2391
109.581
0.45289.975
267.3062219.063
10816.53010.114
10.1140.475
304.037278.035
291.036-14.036
276.999611
10.6460.5
281.207255.026
1942.0648601.585
11.17811.178
0.525294.036
264.962279.499
-13.376266.1228
1211.710
0.55271.186
242.7471675.941
6675.74012.243
12.2430.575
282.624251.890
267.257-12.716
254.540713
12.7750.6
259.768230.468
1421.4005027.043
13.30713.307
0.625269.621
238.818254.220
-12.056242.1631
1413.840
0.65246.758
218.1891179.237
3642.73714.372
14.3720.675
254.781225.746
240.264-11.396
228.867215
14.9040.7
231.889205.910
950.3702509.159
15.43715.437
0.725237.757
212.674225.215
-10.737214.4789
1615.969
0.75214.775
193.631735.891
1611.57116.501
16.5010.775
218.029199.602
208.815-10.077
198.738417
17.0330.8
194.826181.352
537.153933.937
17.56617.566
0.825194.755
186.529190.642
-9.417181.2253
1818.098
0.85171.052
169.073355.927
458.55518.630
18.6300.875
166.390173.457
169.923-8.757
161.166719
19.1630.9
141.538156.794
194.761165.427
19.69519.695
0.925129.309
160.385144.847
-8.097136.7505
2020.227
0.95101.391
144.51558.010
30.87920.759
20.7590.975
53.97076.925
65.447-7.437
58.010221
21.2921
00
Aircraft Data
Lift Calculations
EllipticalTrapezoidal
Appendix N – Structural Analysis Excel sheet used to determine the shear and moment forces for the fuselage.
129
130
Tail774.6963416
main
482.64nose gear
60.00Engine
700.00W
ing Lift Load
10860Tail Lift
Load-1340
Other
1428.00x/L
x (ft)
Wfuse (lbs)
Ww
ing (lbs)W
landing gear (lbs)W
engines (lbs)W
misc (lbs)
Wfuel (lbs)
Wpayload (lbs)
Wtail (lbs)
L wing (lbs)
L tail (lbs)Load (lbs)
V (lbs)M
(lb-ft)
0.0000
00
00
00
00
00
00
00.0499
1.49760
6060
00.050
1.592.775
71.400164.175
224.1750.426
0.1003
92.77571.400
164.175388.350
459.8200.150
4.592.775
71.400164.175
552.5251165.477
0.2006
92.77571.400
164.175716.701
2117.3970.250
7.592.775
71.400160.000
324.1751040.876
3435.5790.300
992.775
154.090233.333
71.400160.000
711.5991752.475
5530.5920.350
10.592.775
154.090233.333
71.400479.645
160.0001191.244
2943.7199052.737
0.40012
92.775154.090
233.33371.400
479.645160.000
1191.2444134.963
14361.7480.4499
13.497-10859.937
-10859.937-6724.974
19670.7590.450
13.592.775
154.09071.400
479.645160.000
957.911-5767.064
19654.4690.499
14.97482.640
482.640-5284.424
19560.7790.500
1592.775
154.09071.400
479.645160.000
957.911-4326.513
19488.6970.550
16.592.775
154.09071.400
479.645160.000
957.911-3368.602
13717.3610.600
1892.775
71.400160.000
324.175-3044.427
8907.5890.650
19.592.775
71.400160.000
324.175-2720.252
4584.0800.700
2192.775
71.400160.000
324.175-2396.077
746.8340.7257
21.76999981339.937
1339.937-1056.139
-1811.3300.750
22.592.775
71.400160.000
324.175-731.964
-1322.2530.800
2492.775
71.400193.674
357.849-374.115
-2151.8120.850
25.592.775
71.400193.674
357.849-16.266
-2444.5980.900
2792.775
71.400193.674
357.849341.584
-2200.6090.950
28.592.775
71.400193.674
357.849699.433
-1419.8471.000
3092.775
71.400164.175
863.608-247.567
Appendix O – Stability Analysis Longitudinal and Lateral directional excel sheets used for stability analysis.
14
131
xcg - xac wing -1.181257 ftmac 5.73 ftXeng 8 ft
AR 8L 0 degl 0.35Sr 226.67 ft2
b 42.58 ftz 0 ftCL cruise 0.26
h 5.25 ftw 5 ftVol of fuselage 396.03 ft3
CL a VT 0.028 per deg
lVT 10.27 ftSVT 65.79 ft2
lVT 0.4 deg
VVT 0.070005(1+ds/db)q/q 1.240081 Eq[11.42]v. tail effect 0.140763 Eq[11.40] stablefuse. effect -0.056009 Eq[11.44] unstablewing effect 0.000672 Eq[11.43] stable
Cnb 0.0854 stable
CL b -0.0854 stable
Input Parametersr 20 degb 11.5 degAsym. T 1219.635 lbsSref 226.67 ft2
b 42.58 ftCnb 0.0854diam eng 5 ftVTO 200 ft/s
r 0.076 lbm/ft3
r 0.002378 sl/ft3
1.2 VTO 240 ft/s0.2 VTO 40 ft/s
q 68.0 lbs/ft2
Deng 1602 lbs
CN R
Asy. Power 0.098554 [rad]-1 Eq[11.47]Cross Wind -0.04912 [rad]-1 Eq[11.50]
daoL/dr -0.48 Eq[11.51]
Cr/CVT 18 % Fig. 11.9
Calculations
Calculations
Vertical Tail Parameters:
Wing Geometric Data
Directional Stability Coefficient:
Rudder Sizing
Wing Parameters:
Fuselage Parameters:
132
CMo -0.091
iht 0
α CLairplane CMcg iht dletaE V (Knots)0 0.209 0.026 4.751 11.88 362.4
1 0.315 -0.007 6.033 15.08 295.32 0.420 -0.039 7.315 18.29 255.53 0.526 -0.072 8.597 21.49 228.34 0.632 -0.104 9.880 24.70 208.45 0.738 -0.137 11.162 27.91 192.86 0.843 -0.169 12.444 31.11 180.37 0.949 -0.202 13.727 34.32 170.08 1.055 -0.234 15.009 37.52 161.29 1.161 -0.267 16.291 40.73 153.7
10 1.266 -0.300 17.574 43.93 147.211 1.372 -0.332 18.856 47.14 141.412 1.478 -0.365 20.138 50.35 136.213 1.584 -0.397 21.421 53.55 131.614 1.690 -0.430 22.703 56.76 127.415 1.795 -0.462 23.985 59.96 123.616 1.901 -0.495 25.267 63.17 120.117 2.007 -0.527 26.550 66.37 116.918 2.113 -0.560 27.832 69.58 113.919 2.218 -0.593 29.114 72.79 111.220 2.324 -0.625 30.397 75.99 108.621 2.430 -0.658 31.679 79.20 106.222 2.536 -0.690 32.961 82.40 104.023 2.641 -0.723 34.244 85.61 101.924 2.747 -0.755 35.526 88.81 99.925 2.853 -0.788 36.808 92.02 98.126 2.959 -0.820 38.090 95.23 96.327 3.065 -0.853 39.373 98.43 94.628 3.170 -0.886 40.655 101.64 93.029 3.276 -0.918 41.937 104.84 91.530 3.382 -0.951 43.220 108.05 90.131 3.488 -0.983 44.502 111.26 88.732 3.593 -1.016 45.784 114.46 87.433 3.699 -1.048 47.067 117.67 86.134 3.805 -1.081 48.349 120.87 84.935 3.911 -1.113 49.631 124.08 83.836 4.016 -1.146 50.914 127.28 82.637 4.122 -1.179 52.196 130.49 81.638 4.228 -1.211 53.478 133.70 80.5
133
AR 8.0b (ft) 42.6 Xcg (ft) 13.5 αol -1.7λ 0.4 Xacwing(ft) 13.5 Cm -0.055
iwing 1.4 XacHT (ft) 22.8 CLα_wing 0.086
SHT (ft2) 126.1 Xbarcg 2.36 CLα_HT 0.066
Sref (ft2) 226.7 Xbaracwing 2.35 dCLair/dα 0.0654
mac (ft) 5.7 XbarHT 3.97 dCM/dα -0.0326
Vht 0.9 xbarnp 16.94266192
lht (ft) 9.3 S.M. 14.59
Vstall (knots) 82.67
r 0.44H 2.00m 0.09dε/dα 0.45
Stability ParametersPositionsAircraft Parameters
15
134
Appendix P – 3 view drawingThree view drawing for final aircraft design.
16
135
136