FOUR SEAT LIGHT PLANE Chris Hayes Matt Mayo

FOUR SEAT LIGHT PLANE Chris Hayes, Matt Mayo, Bryant Ramon

Table of Contents 1) 2) 3) 4) 5) 6) 7) 8) 9) 10) 11) 12) 13) 14) 15) 16) 17) 18) 19) 20) 21) 22) 23) 24) 25) Title Page Table of Contents Problem Statement / Description Requirements Three-Views / Isometrics (Cessna 172 Skyhawk) Three-Views / Isometrics (Cirrus SR 22) Three-Views / Isometrics (Cessna 172 Re-Design) Chapter 1 - Design Proposal Chapter 2 – Preliminary Estimate of Take-Off Weight Chapter 3 – Wing Loading Selection Chapter 4 – Main Wing Design Chapter 5 – Fuselage Design Chapter 6 – Horizontal and Vertical Tail Design Chapter 7 –Engine Selection Chapter 8 – Take-off and Landing Chapter 9 – Enhanced Lift Design Chapter 10 – Structural Design and Material Selection Chapter 11 – Static Stability and Control Chapter 12 – Cost Estimate Chapter 13 – Design Summary and Trade Study Regulatory Compliance Performance Quote Final Rendering of our model (cont. ) Conclusions

Problem Statement / Description Your team works for Cessna and you’ve been charged with proposing a new design to replace/complement the Skyhawk. Your team will propose a new design that can out perform Diamond/Cirrus designs all with the prestigious Cessna nameplate. Your proposal should include a recommendation on 172 retirement, launching a replacement design, upgrading the 172 only or leaving the 172 as is and launching a new design.

Requirements Performance Item Design Payload (Non-Expendable) Passenger Allowance Cabin Length/Width/Height Design Payload (Expendable) Design Range w/Max Payload Design Time-on-Station w/Max Payload Stall Speed Max Cruise Speed = Max Mach AEO Takeoff Field Length OEI Takeoff Field Length (BFL) Landing Field Length AEO Rate-of-Climb OEI Rate-of-Climb Glide Slope Max Sustained Turn Rate Max Instantaneous Turn Rate Service Ceiling Unit Cost Development Cost Altitude/Ambient Velocity/Mach ISA Vmax Solve / ISA Vmax / Vbe Sea Level / ISA Solve Cruise Altitude / ISA Solve Sea Level / ISA Vtakeoff Sea Level / ISA Vopt (Cruise Altitude/2) / ISA Vopt Cruise Altitude / ISA Vopt Solve / ISA Vopt - Flaps Clean Clean Flaps Clean Clean - Weight Wo Requirements/ Targets 1 Pilot / 3 pax 250 lbs/pax 12’/4’/4’ Wo 0 Wo 800 nm Wo 0 Wo <45 nm/hr Cruise >160 nm/hr Wo <1, 800 ft Wo n/a Wo-(Wf/2) <1, 500 ft Wo >900 ft/min Wo n/a Landing <3 deg Cruise >2 deg/s Cruise >2. 5 deg/s Cruise >20, 000 ft <$350, 000 <$11 M

Three-Views / Isometrics • Cessna 172 Skyhawk Source: http: //www. theblueprints. com/en/blueprints/modernplanes/cessna/18078/view/cessna_172_skyhawk/

Three-Views / Isometrics • Cirrus SR 22 • Source: http: //servicecenters. cirrusdesign. com/Tech. Pubs/pdf/POH/sr 22 -002/pdf/20880 -002 Info. Manual. pdf

Cessna 172 Redesign

Design Proposal • Re-Designing the Cessna 172 Skyhawk • Passenger allowance of 250 lbs/pax • Cabin Dimensions of 12’/4’/4’ • Design Range (with Max Payload) of 800 nm • Faster cruise than Cirrus SR 22

Preliminary Estimate of Take-off Weight Design Weight Summary Assumptions(using Corke atmosphere model) Mission Analysis Summary • SFACT: 0. 5280 Parameter Symbol Empty Weight (lb) We • Corke Table 2. 3 Payload (lb) Wp -Expendable Wpe • Lift-to-Drag ratio: 13. 0 -Non-expendable Wpne Fuel Load (lb) Wf • Corke Figure 2. 4 -Mission Fuel Burned Wfb -Reserves Fuel Wr • SFC: 0. 7713 -Trapped Fuel Wtf Design Takeoff Gross Weight (lb) Wo • Updated with Engine Spreadsheet Surplus Empty Wt. (lbs) Design Problems Benchmarking Janes W 0 Cessna Redesign W 0 Del% Cirrus SR 22 3, 600 (lb) 3, 967. 0 (lb) 10. 2% heavier Cessna 172 2, 450 (lb) 3, 967. 0 (lb) 61. 9% heavier (W/Wo) Weight Value Fraction 2, 094. 6 0. 5280 1, 000. 0 0. 2521 0. 0000 1, 000. 0 0. 2521 872. 4 0. 2199 823. 0 0. 2075 41. 2 0. 0104 8. 2 0. 0021 3, 967. 0 1. 0000 0. 00

Wing Loading Selection Assumptions(using Corke atmosphere model) • Cl, max: 2. 314083922 • Chapter 4 spreadsheet • Cd 0: 0. 0161 • Chapter 7 spreadsheet • e: 0. 8 • Accepted value given by Corke • Takeoff Max Thrust: 906 lbs • Calculate to obtain climb rate Benchmarking Jane’s W/S Cessna Redesign W/S Del% Cirrus SR 22 24. 8 17. 81 28. 2% Cessna 172 14. 1 17. 81 26. 3% Design Wing Loading Summary Wing Loading Selection Summary Design Wing Loading W/S (lb/f^2) Parameter No. Flight Regime 1 AEO Take-off S_TO (f) 2 Landing 17. 81 Value Target Del% 945. 8 1800. 0 -47% S_L (f) 1, 119. 9 1500. 0 -25% 3 Cruise Start S (f^2) 222. 7 4 Cruise End H (f) 10, 000. 0 5 AEO Climb d. H/dt (f/min) 731. 1 900 6 Acceleration n 7. 149 7 Turn - Instantaneous psi_dot (deg/s) 7. 270 2. 5 191% 8 Turn - Sustained psi_dot_act (deg/s) 7. 259 2. 0 263% 9 Ceiling H (f) 36, 937. 4 20000 85% 2. 490 3 -17% 47. 6 45 6% 10 Glide Gamma (deg) 11 Stall Speed Vstall (ktas) Design Problems -19%

Main Wing Design Assumptions(using Corke atmosphere model) • Aspect Ratio: 7. 5 • JAWA 2013 • LE Sweepback: 0 • Not required for light airplanes • Airfoil: NACA 2412 Same airfoil as the Cessna 172 S based on wikipedia • Interference factor: 1 • Corke Table 4. 2 • Benchmarking Cirrus SR 22 Cessna 172 Cessna Redesign 10 7. 32 7. 5 Taper Ratio 1 1 LE Sweep 0 0 Aspect Ratio Max (t/c) . 28 . 12 Airfoil Description Roncz NACA 2412 1. 7 1. 5 CL, Max Main Wing Design Summary b Meff cr ct m. a. c. b 40. 87 ft 0. 250 5. 45 ft 5. 4 ft 0. 9682 CLa 0. 0863 1/deg CLo 0. 1726 atrim CLtrim k CD L/D Total Drag 0. 54 deg 0. 2192 0. 0531 0. 0133 16. 48 185. 9 lbf Design Problems

Fuselage Design Assumptions(using Corke atmosphere model) • Inverse Fineness: 7. 11 Viscous Drag Calculations: x/L x (ft) 0. 00 0. 10 0. 20 0. 30 0. 40 0. 50 0. 60 0. 70 0. 80 0. 90 1. 00 • Corke Table 5. 11 • Max Diameter: 4. 5 • Design Driver • Interference factor: 1 • Corke page 107 • Fuselage shape: Elliptical Cylinder • Fuselage Design Summary Elliptic Cylinder Fuselage Shape H (ft) 0. 0 3. 2 6. 4 9. 6 12. 8 16. 0 19. 2 22. 4 25. 6 28. 8 32. 0 W (ft) 1. 00 2. 50 4. 00 2. 40 1. 40 0. 90 0. 50 P (ft) 1. 00 2. 50 4. 00 2. 40 1. 40 0. 90 0. 50 3. 1 7. 9 14. 1 12. 6 7. 5 4. 4 2. 8 1. 6 Totals: subsonic Benchmarking Cirrus SR 22 Cessna Re-Design Del% Inverse Fineness 5. 4 7. 11 31. 7% Max Diameter 4. 8 4. 5 6. 3% Total Drag 90 61. 3 31. 9 % Cessna 172 Cessna Re-Design Del% Inverse Fineness 6 7. 11 18. 5% Max Diameter 4. 75 4. 5 5. 3% Total Drag 37. 5 61. 3 63. 5% Design Problems Sw(ft^2) Rex 25. 1 45. 2 40. 2 24. 1 14. 1 9. 0 5. 0 298. 6 4. 5 E+06 9. 0 E+06 1. 4 E+07 1. 8 E+07 2. 3 E+07 2. 7 E+07 3. 2 E+07 3. 6 E+07 4. 1 E+07 4. 5 E+07 CF 3. 40 E-03 3. 04 E-03 2. 85 E-03 2. 72 E-03 2. 63 E-03 2. 56 E-03 2. 50 E-03 2. 45 E-03 2. 41 E-03 2. 37 E-03 Drag (lbf) Volume (ft 3) 6. 4 10. 2 9. 6 9. 2 8. 8 7. 6 4. 5 2. 6 1. 6 0. 9 8. 2 31. 6 50. 9 45. 4 26. 3 9. 3 3. 4 1. 3 61. 3 278. 1

Horizontal and Vertical Tail Design Assumptions(using Corke atmosphere model) • Aspect Ratio: 1. 3 vertical, 3 horizontal • Corke Table 6. 5 in range • Taper Ratio: 0. 5, 0. 5 • Corke Table 6. 5 • LHT / LVT: 18 ft / 18 ft • Corke page 126 Benchmarking Cirrus SR 22 Cessna Redesign Aspect Ratio 1. 3/3. 0 Taper Ratio 0. 5/0. 5 LE Sweep 35/15 Max (t/c) 0. 35/0. 35 Airfoil Description NACA 63 -006 CL, Max 0. 8/0. 8 Tail Design Summary Conventional T-Tail Cruciform H-Tail V-Tail Inverted V-Tail Y-Tail Twin Tail Control Canard Lifting Canard Airfoil Section Max Thickness, % LE Sweep, deg Aspect Ratio, d. CL/da, 1/deg Total Drag (lbf) 56. 9 54. 3 56. 1 58. 1 53. 6 55. 8 59. 8 56. 9 Main Wing 0. 120 0. 0 Del% Base -4. 6% -1. 5% 2. 1% -5. 9% -1. 9% 5. 1% 0. 0% Vertical Tail NACA 63 -006 0. 060 35. 0 1. 300 0. 0320 Design Problems VT TE Sweep (deg) 10. 6 10. 6 Horizontal Tail NACA 63 -006 0. 060 15. 0 3. 000 0. 0594

Engine Selection Assumptions(using Corke atmosphere model) Design Parameters Cessna Redesign Gross Weight 3, 967. 0 lbs Reference Wing Area 222. 7 ft^2 Wing Loading 17. 81 Cruise Altitude 10, 000 ft Cruise Speed/Mach 159. 5/0. 25 Bleed 0. 02 Reference Engine PT 6 A-50 Engine Scale Factor 1. 0 Scaling Methodology Eqns. 7. 8 -7. 11 Engine Selection Summary Number of Engines Uninstalled Engine Power, SLS ISA Max Reference Engine Scale Factor Type of Engine Ave. SFC, @ Design Cruise Engine Weight Engine Length Engine Max Diameter Propeller Diameter # of Blades Benchmarking Engine Cirrus SR 22 Cessna 172 Cessna Redesign Power 160 945 SFC 0. 4313 0. 7494 Weight 430. 72 lbs 258 lbs 215. 6 Length 38. 43 in 33. 6 in 39. 6 in Width: 18 in Height: 25 in Width: x in Height: x in Diameter Engine Selection Summary Propeller Diameter 6. 667 ft 6. 25 ft 7 ft Number of Blades 3 2 2 Design Problems Value 1 945. 0 PT 6 A-50 1. 000 Turboprop 0. 7494 215. 6 39. 6 19. 6 7 2 Units shp/eng lbm/hr/shp lbf/eng in in ft -

Take-off and Landing Assumptions(using Corke atmosphere model) Design Parameters Takeoff and Landing Summary Cessna Redesign Gross Weight 3274 Reference Wing Area 222. 7 ft^2 Wing Loading 9. 21 Gear Frontal Area 151. 58 ft^2 Takeoff/Landing Flap deflection angle 30/60 Cl_max 1. 1/1. 55 Obstacle Height 50/50 Friction Coefficient 0. 4 (Roll 0/0. 5 (Brake) Takeoff and Landing Summary Rationale Adjust lift curve Design Gross Weight lbf Altitude ft Engine Thrust lbf/eng Stall Speed nm/hr Field Lengths AEO Takeoff ft OEI Takeoff ft Landing ft Regulatory Compliance AEO, Gear Up Vy ft/min OEI, Gear Up G % OEI, Gear Down G ft/min Benchmarking Design Problems Cirrus SR 22 Cessna 172 AEO field length OEI field length Landing field length Cessna Redesign 961/1061 - - 961/1061 3967 0 906 47. 7 2, 021 #NAME? 2, 231 704 0 0. 0%

Enhanced Lift Design Flap Design Summary Type of TE Flaps LE Flaps Flap Area / Wing Area, Swf/Sw Flap Deflection Angle, df Flap Chord / Wing Chord, cf/c Flap Span / Wing Span, bf/b CL, max DCDo, flaps Design plain No 0. 50 40. 00 0. 40 Units deg - 0. 50 - 2. 31 - 0. 0863 - Benchmarking Flap type Wing Platform Plot Wing Planform Wing Half Span, b/2, (ft) Assumptions(using Corke atmosphere model) 15 12 9 6 3 0 0 3 6 9 Axial Position, (ft) Design Problems Cirrus SR 22 Cessna 172 Cessna Redesign Plain plain Flap Chord/ Wing Chord 3. 6028/7. 2 Flap Span/ Wing Span 21. 617/54. 04 S_wf/S_w 194. 7/389. 4 12 15

Structural Design and Material Selection Wing Platform Plot V-n Diagram Structure Material Summary Structure/Material Summary X-Section Material Group Material Tension (W 1/W 2)t Compression (W 1/W 2)c Bending (W 1/W 2)b # of Wing Spars Spar Deflection (in. ) Spar Height < Wing Thickness ? # of Bulkheads Bulkhead Spacing (in. ) # of Longerons Longeron Height < Fuse. Wall Wing Fuselage Skin Spar Skin Longerons Airfoil I Beam Hollow Ellipse Hollow Circle Aluminum Alloy Steels Aluminum Alloy 2024 -T 3 (clad) 4130 Normalized 2024 -T 3 (clad) 1. 000 1. 728 1. 000 2. 447 1. 000 2. 211 1. 000 X 1 X X X 10. 00 X X X YES X X X 14 X X X 28. 30 X X X 8 X X X YES Design Problems

Static Stability and Control Static Stability & Control Summary Final Weight Breakdown Weight Summary Component Wing Horizontal Tail Vertical Tail Fuselage Main Gear Nose Gear Engine(s) Remaining Components Empty Weight Design Gross Weight Empty Weight Fraction Symbol Wwing Wh-stab Wv-stab Wfuse Wmain lg Wnose lg Weng Wrem We Wo We/Wo General Fighter Transport Aviation 631 512 487 67 18 26 20 41 26 794 888 303 112 77 180 59 30 32 553 595 674 555 2, 910 2, 793 2, 204 3, 967 0. 734 0. 704 0. 556 Rudder Design V-Stab Span, (ft) 5 4 3 2 1 0 2 4 Axial Position, (ft) Static Margin -Center of Lift -Center of Gravity -Static Margin @ Wcr, start -Dtrim / Dtotal Stability Coefficients -Longitudinal, Cm, a -Lateral, CL, b -Directional, Cn, b Rudder Area Value. Comments 0. 3553 xcl/L 0. 3401 xcg/L 9. 0%stable 0. 146 Dtrim high, See Corke Page 279 -0. 0019 stable Corke: -1. 5<Cm, a<-0. 16 -0. 1715 stable Corke: 0. 08<Cn, b<0. 28 2. 3 ft 2 Design Problems V-Stabilizer Planform 0 Static Stability & Control Summary 6

Cost Estimate Pie Chart (1986 CER’s) Cost Estimate Summary Year Number of Development Aircraft Number of Production Aircraft Production Rate (per month) Amortization Period (# of ac) C_P ($) 1986 CERs Cost Estimate in 9% 2013 Dollars 2013 2 5300 50 4000 C_EN ($) 1% C_E ($)C_D ($) 5% 1% C_QC ($) 7% C_T ($) 5% C_MM ($) 25% Initial Unit Cost (1986 Model) Final Unit Cost (1986 Model) Initial Price Markup Profit (%) C_ML ($) 47% $689, 852 $661, 368 4% 10 Proposed Cost vs. Requirement Proposed Cost Requirement Del % $661, 368 $350, 000 89. 0% Design Problems

Trade Summary Design Summary 172 Re-Design Cessna 172 Weights W_TO (lb) W_S W_F (lb) W_P (lb) s_fact Wing S (ft^2) b (f) W/S (lb/ft^2) Fuselage L (f) H(f) Engines # of T_max (lb) T/W Takeoff/Landing S_TO (ft) S_L (ft) Cirrus SR 22 3967 2094. 6 872. 4 1000 0. 528 2189. 4 1402. 2 188. 2 599 0. 6404 2077. 8 1243. 3 234. 5 600 0. 5984 222. 7 40. 87 17. 81 139. 6 36. 08 15. 68 145 38. 33 22. 07 32 7 27. 2 8 26 8. 92 1 906 ? 0. 2284 ? 2021. 1 1324. 6 1 Trade Study • Wanted to see the effect of a more efficient engine or increased cruise Mach would have on range 1 ? ? 1630 1335 1756 1178 Trade Study Results Cruise Mach vs Range (nm) 880 Specific Fuel Consumption vs Range (nm) 1200. 0 1000. 0 800. 0 600. 0 Range (nm) 400. 0 Range (nautical miles) Range (nautical Miles) 1400. 0 860 840 820 800 780 760 740 200. 0 720 0. 0 0 0. 5 1 1. 5 2 Specific Fuel Consumption (lb/(lbf·h)) 0 0. 1 0. 2 0. 3 0. 4 0. 5 Cruise Mach 0. 6 0. 7 0. 8

Regulatory and Design compliance Regulatory Compliance Certification (FAR Part 23) Velocities Takeoff Climb Gradient Rolling Friction Obstacle Height Emergency Exits Max Load Factor Design Compliance Airfoil Cross Section, Taper, Sweep Crew Sight Lines Fuselage Volume Tail Geometry – Aft VT TE Sweep<20 deg page 136 Tail Placement – Stall Control Tail Placement – Spin Recovery Propeller Tip Speed/Mach < 0. 85 Longitudinal Static Stability Directional Static Stability Trim Drag Corke Reference Your Design Status V_TO>1. 1 Y_Stall 300 fpm @ sea level n/a 50 feet 1 type IV load factor <3. 1 Compliant compliant n/a compliant Sections 4. 1 -4. 3 Table 5. 8, page 95 Section 5. 1 Tables 6. 1 -6. 6, pages 123 -128 compliant compliant compliant Figure 6. 9, page 129 Figure 6. 10, page 131 page 152 Equation 11. 26 Equation 11. 45 Equation 11. 61

Performance Quote Performance Item Requirements/ Targets Proposed Design -Design Payload (Non-Expendable) -Passenger Allowance -Cabin Length/Width/Height -Design Payload (Expendable) -Design Range w/Max Payload -Design Time-on-Station w/ Payload -Stall Speed -Max Cruise Speed = Max Mach -AEO Takeoff Field Length -OEI Takeoff Field Length (BFL) -Landing Field Length -AEO Rate-of-Climb -OEI Rate-of-Climb -Glide Slope -Max Sustained Turn Rate -Max Instantaneous Turn Rate -Service Ceiling -Unit Cost -Development Cost 1 Pilot / 3 pax 4 250 lbs/pax 12’/4’/4’ (192 ft^3) 0 800 nm 0 <45 nm/hr >160 nm/hr <1, 800 ft n/a <1, 500 ft >900 ft/min n/a <3 deg >2 deg/s >2. 5 deg/s >20, 000 ft <$350, 000 <$11 M n/a 4 250 lbs/pax n/a 194 ft^3 1% 0 n/a 800 nm 0% 0 n/a 47. 6 ktas -5. 7% 158. 5 ktas -0. 9% 2021. 1 ft n/a 1324. 6 ft 11. 7% 704 ft/min n/a 2. 49 deg 17% 5. 64 deg/s 182% 7. 27 deg/s 190. 8% 36, 900 ft 84. 5% $689, 850 97. 1% $113, 900, 000 -935. 5% Delta% Cessna 172 Cirrus SR 22 4 250 158 ft^3 0 640 nm 0 48 ktas 124 ktas 1630 ft n/a 1335 ft 730 ft/min n/a 6. 34 deg 22. 2 deg/s 13. 8 deg/s 14, 000 ft $364, 000 $68, 200, 000 250 184 ft^3 0 400 nm 0 60 ktas 183 ktas 1756 ft n/a 1178 ft 1270 ft/min n/a 5. 95 deg 17. 6 deg/s 11. 11 deg/s 17, 500 ft $664, 900 $141, 800, 000

Final Rendering of our model

Final Rendering of our model (cont. )