1. Team 5 Critical Design Review Trent Lobdell Ross May Maria Mullins Christian Naylor Eamonn Needler Charles Reyzer James Roesch Charles Stangle Nick White

2. 2 AAE 451 – Team 5 March 24, 2005 Outline Mission Requirements Team Design Aerodynamics Dynamics & Control Propulsion Structures / Landing Gear Prediction of Vehicle Performance Remaining Design Problems

3. 3 AAE 451 – Team 5 March 24, 2005 Requirements Design Requirements & Objectives  Take-Off and landing distance: 100 ft*  Take-Off with minimum climb angle: 20°  Endurance: 15 min*  Typical descent angle of: 5.5°  Stall Speed: 20 ft/s  Loiter Speed: 28 ft/s*  Minimum Turn speed: 23.33 ft/s*  Turn Radius: 35 ft*  Operating Altitude: 18 ft*  Operational Airspace: 360x150 ft *Changed Requirements from Mission Specification

4. 4 AAE 451 – Team 5 March 24, 2005 Design Features Features / Unique Aspects  Stealth Theme  Twin Booms  Pusher Prop  Multi-Sweep Wing Predicted Weight: 0.84 lbf

5. 5 AAE 451 – Team 5 March 24, 2005 Design Properties Wing Fuselage Horizontal Tail Vertical Tail Overall Aircraft

6. 6 AAE 451 – Team 5 March 24, 2005 Design - Dimensions

7. 7 AAE 451 – Team 5 March 24, 2005 Aerodynamics - Airfoils Low Re Number  91903 (Stall) - 128660 (Cruise) Wing  Eppler E212 Tail  Eppler E169 Horizontal Tail  NACA 0010 Vertical Tail NASG: http://www.nasg.com/afdb/search-airfoil-e.phtml UIUC: http://www.aae.uiuc.edu/m-selig/ads/coord_database.html

8. 8 AAE 451 – Team 5 March 24, 2005 Aerodynamics – Geometry Defined Sweep Angles (Λ) Defined taper ratio (λ) of 1 st segment Defined Span Ratio of 2 segments Adjust to balance  Style  Aspect Ratio  Tip Chord feasibility

9. 9 AAE 451 – Team 5 March 24, 2005 Aerodynamics - Lift Lift Coefficients vs. α α (deg) C L and C l C Lmax (Hembold): 0.74 Max Lift (Hembold): 1.10 lbf Sweep Corrected Hembold Equation 1 1 Anderson, J.D., Fundamentals of Aerodynamics, New York, 2001, pp 351-416 Prandtl Lifting Line Theory 1

10. 10 AAE 451 – Team 5 March 24, 2005 Aerodynamics - Drag Parasite Drag Buildup S ref = reference area [ft 2 ] C f = skin friction coefficient K = form factor Q = interference factor

11. 11 AAE 451 – Team 5 March 24, 2005 Aerodynamics – L/D L/D max =13.21 Loiter at α=.71°,4.46° Loiter at 0.866*L/D max 2 Wing Incidence: 3° Tail Incidence: -7.3° α (deg) L/D L/D vs. α 2 Raymer, D.P., Aircraft Design: A Conceptual Approach, Virginia, 1999, pp 27 L/D=4.7

12. 12 AAE 451 – Team 5 March 24, 2005 Class 2 Tail Sizing (X-plot)

13. 13 AAE 451 – Team 5 March 24, 2005 Trim Diagram

14. 14 AAE 451 – Team 5 March 24, 2005 Control Surface Sizing Aileron size / dimension:  Area:0.04 ft 2  Length: 0.63 ft  Root Chord: 0.08 ft  Tip Chord: 0.05 ft Elevator size / dimension:  Area: 0.10 ft 2  Span: 0.50 ft  Chord: 0.21 ft Rudder size / dimension:  Area: 0.02 ft 2  Base 1: 0.04 ft  Base 2: 0.15 ft  Height: 0.19 ft

15. 15 AAE 451 – Team 5 March 24, 2005 Class 2 Vertical Tail Sizing (X-plot) 0.218 ft 2

16. 16 AAE 451 – Team 5 March 24, 2005 Feedback Controller Pitch Rate Feedback to Elevator

17. 17 AAE 451 – Team 5 March 24, 2005 Feedback Controller Damping Ratio w/o Feedback = 0.74 Desired Damping Ratio = 0.35 – 1.3 We chose a Damping Ratio = 0.95 Feedback Gain Required = 0.07

18. 18 AAE 451 – Team 5 March 24, 2005 Propeller Take-Off Characteristics Type2-Bladed3-Bladed Propeller Diameter6 in5 in Pitch4 in3 in Operating RPM14300 RPM16400 RPM Efficiency0.610.60

19. 19 AAE 451 – Team 5 March 24, 2005 Propeller Plots – 6 inch prop Take-Off Loiter C T = 0.076 C P = 0.042 η =.61 C T = 0.025 C P = 0.023 η =.83

20. 20 AAE 451 – Team 5 March 24, 2005 Motor Selection - Graupner Speed 400 6V (Direct Drive) Characteristics Engine CharacteristicsPropeller Shaft Diameter0.091 in Engine Diameter1.08 in Engine Length1.5 in Weight2.55 oz Rated Horsepower0.12 hp Rated Loaded RPM15500 RPM Operating ConditionsOperating RPM (Take Off)14300 RPM Input Voltage8.34 Volts Input Current11.7 Amps Output Power0.078 hp

21. 21 AAE 451 – Team 5 March 24, 2005 Battery & Speed Controller Selection Thunder Power 3 Cell Li-Po  Rated for 12-15 Amps  2100 mAh Allows for extended endurance as specified in the DR&O  4.6 oz. JETI 12 Amp Microprocessor Motor Controller  For 2-3 Cell LiPo  Weight = 0.53 oz.  1x0.75x0.3 in.

22. 22 AAE 451 – Team 5 March 24, 2005 Landing Gear Main gear (2)  Single beam, t = 0.0017 ft  Stroke = 0.0458 ft  Weight = 0.0018 lbf  30° angle for lateral stability  20° in front of CG for longitudinal stability  Absorb impact Gear deform instead of break  Easy to change Tail Gear (2)  18 gauge steel wire  Prevent prop and tail strike Gear deform instead of break Parameters θ = 30° Material = Al Ngear = 3 (Gen. Av.)

23. 23 AAE 451 – Team 5 March 24, 2005 Structures - CG

24. 24 AAE 451 – Team 5 March 24, 2005 Structures - Load Analysis Structural loads from code – basic equations used  τ max = 2.40 lbf/ft 2  M root = 0.26 ft-lbf  σ max = 0.0048 lbf/ft 2 Deflections  δ y = 9.1e -11 ft  δ Φ = 1.1e -4 degrees

25. 25 AAE 451 – Team 5 March 24, 2005 Structures - Load Analysis Torsion Loads  T = 0.1 ft-lbf. at high maneuver Failure of wing (most likely due to buckling) occurs at  n cr = 38 or at σ cr = 32 psf.

26. 26 AAE 451 – Team 5 March 24, 2005 Scheduled Tests Drop Test  Height of 2.5 ft  Tests landing gear and crash survivability Wing Load Test  Test maximum load of wing Flight Test  Propeller test  Feedback gain test  Control surface test

27. 27 AAE 451 – Team 5 March 24, 2005 Strength Testing Failure at 26 lbf

28. 28 AAE 451 – Team 5 March 24, 2005 Strength Testing Failure due to buckling

29. 29 AAE 451 – Team 5 March 24, 2005 Manufacturing Wing/fuselage and tails milled using CNC Wet lay-up with 0.6 oz. bidirectional s-glass Holes cut and tapped for component placement Epoxy bonding of tails and booms Mechanical attachment of landing gear, motor, etc.

30. 30 AAE 451 – Team 5 March 24, 2005 Manufacturing - Booms Circular holes cut for boom insertion Foam is bonded inside and out to tube Boom pinned into place with wire

31. 31 AAE 451 – Team 5 March 24, 2005 Overall Schedule To be accomplished before 1 st flight Order parts – March 10 Build prototype wing – March 11 Test prototype strength – March 22  CDR – March 24  CNC Parts – by March 28  Fiberglass Parts – by April 3  Build – by April 7  Test and modify – until flight date

32. 32 AAE 451 – Team 5 March 24, 2005 Predicted Flight Performance Max. Turning Radius: 35 ft (DR&O)  Bank Angle: 34.82°  Turn Rate: 0.8 rad/s Min. Turning Radius: 10.92 ft (Limit)  Bank Angle: 65.85°  Turn Rate: 2.57 rad/s Maximum Climb Angle: 26.77° Take-Off Distance: 16.29 ft Landing Distance: 22.48 ft

33. 33 AAE 451 – Team 5 March 24, 2005 Current Issues Propeller air flow Engine heating Manufacturability  Boom attachments  CG movement