S+C, PERFORMANCE PDR

1. S+C, PERFORMANCE PDR Stability and Control Preliminary Design Review and Performance PDR October 24, 2000 Presented By: Christopher Peters …and that’s cool Team DR2 Chris Curtis Loren Garrison Jeff Rodrian Mark Blanton

2. S+C, PERFORMANCE PDR Presentation Outline: • Stability and Control • Empennage sizing • Control Surface Sizing • CG, AC and NP Locations • Trim Discussion • Static Margin • Dutch Roll Mode • Short Period Mode • Performance • Take-off and Climb • Turn • Endurance • Projected Plan

3. S+C, PERFORMANCE PDR Empennage Sizing: • Class I Sizing Approach • Sizing with Tail Volume Coefficients • Vvt,Vht – ROSKAM II, SEC8 • Vvt = 0.04 • Vht = 0.5 • Determined from Historical Data for small GA Aircraft, Homebuilt and Production. • VT area generally too big… • Need Class II Sizing to justify Size Selection • HT and VT analyzed using Class II Sizing

4. S+C, PERFORMANCE PDR Empennage Sizing: • Class II Sizing Approach • HT • Size HT using Center of Gravity (CG), Static Margin (SM), Tail Volume Coefficient (Vht) and HT-Moment Arm (lht) Information. • VT • Size VT using CG, Cnβ, Tail Volume Coefficient (Vvt), and VT-Moment Arm (lvt) Information.

5. S+C, PERFORMANCE PDR Empennage Sizing HT: • For Electric Model Design assume the ability to pick CG by internal arrangement of Avionics and Electronics, to fit Desired SM • Pick SM to fit Mission • Modification of X-Plot Method necessary • Analyze HT for Trimmed flight and Geometry Limitations

6. S+C, PERFORMANCE PDR Empennage Sizing HT: • SM, 18% is Design Goal • Possible Travel to Account for: 10%-25% • Due to Component Shift and Mission Modifications • Neutral Point Location (Xnp) Determined thru Trim-Analysis • CG Set

7. S+C, PERFORMANCE PDR • Empennage Sizing HT: • Neutral Point Derivation: • Calculation of lht by Sht Variation – Limited by Length of Fuselage:

8. S+C, PERFORMANCE PDR • Empennage Sizing HT Solution: Sht = 2.25ft2 ARht = 4 bht= 3.0 ft cht = 0.75 ft Vht = 0.5 lht = 3.171 ft

9. S+C, PERFORMANCE PDR Empennage Sizing VT: • Vvt Variation for Svt Calculation determined by Weathercock Criterion for ‘Manned Aircraft’: • Simultaneously Calculation of lvt by Vvt Variation – • Iteration Process, Cnβ update – Effects on Dutch Roll Mode • Weathercock: Cnβ >= 0.057 rad-1

10. S+C, PERFORMANCE PDR • Empennage Sizing VT Solution: Svt = 0.77ft2 ARvt = 2.5 bvt= 1.39 ft cvt = 0.56 ft Vvt = 0.024 lvt = 3.38 ft SvtHIST = 1.69ft2

11. S+C, PERFORMANCE PDR Control Surface Sizing : • Control Surface Sizing thru Class I Method: • Estimation based on Empirical Data • From ROSKAM II/8 and former 451 Reports: • Elevator: 40%croot – 45%ctip , Full Span • Rudder: 35% croot - 48% ctip, Full Span • Aileron: 25% cw – 60% Span • Deflection Limits: • Rudder/Elevator: +/- 10º • Flat Plate Airfoil Approximation – Separation • No Dihedral, Rudder and Aileron Control

12. S+C, PERFORMANCE PDR Aerodynamic Center, CG, SM: • Aerodynamic Center Wing • 23% of Cmean – For Biplanes (Raymer) • Aerodynamic Center Aircraft • As shown Before, Xnp = 1.85ft (from FS 0, - Nose of A/C) • CG • SM = 18%, CG = FS 1.68 • SM = 10%, CG = FS 1.75 • SM = 25%, CG = FS 1.61

13. S+C, PERFORMANCE PDR Aerodynamic Center, CG, SM: • CG Calculation, Mass Inertias • Component Shift to meet SM = 18% • Determine Mass Inertias for given CG • Ixx = 0.5 slugs-ft^2 • Iyy = 0.54 slugs-ft^2 • Izz = 0.96 slugs-ft^2

14. S+C, PERFORMANCE PDR Trim: Force and Moment Balance

15. S+C, PERFORMANCE PDR Moment Coefficient: iwu= 0 deg iwl= -2 deg iht= 0 deg

16. S+C, PERFORMANCE PDR Trim Conditions

17. S+C, PERFORMANCE PDR Trim Conditions

18. S+C, PERFORMANCE PDR Dutch Roll Mode: ζDR = 0.212 ωDR =2.102

19. S+C, PERFORMANCE PDR Short Period Mode Approximation (after DR K. Hout): ζSP = 0.57 ωSP =5.62

20. S+C, PERFORMANCE PDR Performance • Endurance • After propulsion PDR II • Endurance Requirement met and exceeded at Vloiter=25 ft/s • Takeoff Distance • Less than 35 ft • At Climbangle > 6deg. • Easily meeting abort mission and climb constraints

21. S+C, PERFORMANCE PDR Performance • Projected Work • Detailed Analysis of Performance Parameters • Take-off • Turning • Dynamic Simulation of Aircraft • Mission Analysis with finalized Parameters