1. AE 10 Airplane Design

2. Preliminary Aircraft Design Process 1. Mission Specification 2. Configuration Design 3. Weight Sizing 4. Performance Sizing 5. Fuselage Design 6. Wing Design 7. Empennage Design 8. Landing Gear Design 9. Weight & Balance Analysis 10. Stability & Control Analysis 11. Drag Polar Estimation 12. Final Design

3. 1. Mission Specification  What exactly is the airplane expected to do? Ex. TWA specifications for a modern luxury transport – 02 Aug. 1932: All metal tri-motor monoplane All metal tri-motor monoplane Carry 12 passengers Carry 12 passengers Range = 1,080 st. mi. Range = 1,080 st. mi. Crew = 2 Crew = 2 Top Speed @ sea level = 185 mph (min) Top Speed @ sea level = 185 mph (min) Cruise Speed @ sea level = 146 mph Cruise Speed @ sea level = 146 mph Landing Speed = 65 mph (max) Landing Speed = 65 mph (max) Service Ceiling = 21,000 ft (min) Service Ceiling = 21,000 ft (min) Rate of Climb = 1,200 fpm Rate of Climb = 1,200 fpm Max Gross Weight = 14,200 lbs Max Gross Weight = 14,200 lbs Passenger cabin must have ample room for comfortable seats, miscellaneous fixtures and conveniences. Passenger cabin must have ample room for comfortable seats, miscellaneous fixtures and conveniences. Airplane must have the latest radio equipment, flights instruments, and navigational aids for night flying Airplane must have the latest radio equipment, flights instruments, and navigational aids for night flying

4. DC-1

5. Requirements are extremely important because they  Drive the design  Are the yardstick by which the success of the design is measured

6.  Aircraft companies have lost large amounts of $$ because they followed a bad or inappropriate set of requirements:

7. Spruce Goose (Hercules), 1947 Designed by Howard Hughes 700 passenger (cargo + troop carrier) 8 x 3,000 hp 8-cylinder engines: largest piston engines ever produced for an ac Urgent government project in 1942, had lost all priority by 1944

8. 1 st supersonic bomber: North American XB-70 Valkyrie, 1964

9. C-5 Galaxy, June 30, 1968 LG Design, LG: 28 wheels, tires can be inflated / deflated in fight !

10. Length = 3 – 4 in. Weight = 0.25 oz. Takeoff & Landing: Vertical Speed = 60 mph Range = 1 mile Flight Altitude: less than 1,000 ft Heart Rate: 1,200 / min (20 / sec) Wing Beats: 70 - 200 / sec Control: Very Precise Refueling: In-flight Consumes: 155,000 calories / day its own weight in fuel every 18 hrs its own weight in fuel every 18 hrs Visits 2,000 flowers / day to feed To sustain same level of activity a human would have to eat 220 lbs of hamburger per day.

11. Trumpeter Swan takeoff Lake Michigan

12. 2. Configuration Design Refers to the positioning of the major parts of the airplane  Wing  Fuselage  Empennage  Engines  Landing gear in relation to each other. What will the airplane look like?

13. An – 225 with Buran

14. 2. Configuration Design  Ideal configuration: the cg of W E, W F, W PL are all at the same longitudinal location. Why? –Limits cg travel. –Reduces S wet because there is less need for trim control power.  Think: –Light –Simple –Accessibility –Maintainability –Cost

15. 2. Configuration Design  Minimize interference D.  At high M<1 it may be necessary to apply local area ruling to reduce D wave (B-747)

17. 2. Configuration Design  For M>1 airplanes, area ruling at several M is necessary. Ideal shape: Sears-Haack body of revolution

18. 2. Configuration Design  Structural Synergism: major intersecting structural components should be arranged to avoid duplication of special heavy structure.

19. Piaggio P – 180 Avanti

20. Preliminary Sizing  Weight Sizing  Performance Sizing

21. 3. Weight Sizing  TOW or W TO is a very important design parameter; it sizes the entire vehicle –Wing size = f (W TO ) –Landing Gear size = f (W TO ) –Acquisition Cost = f (W TO )

23. 4. Performance Sizing To determine:  Wing Area S  Takeoff Thrust T TO (jet ac) or Takeoff Power P TO (propeller ac)  Maximum Lift (C Lmax ) for clean, takeoff, landing configurations

24. Typical Performance Requirements  Field length –Takeoff d TO –Landing d LND  Speed –Stall V s –Cruise V cr –Maximum V max

25. Typical Performance Requirements  Climb –Rate-of-climb (ROC) – AEO, OEI –Time-to-climb (TTC) to some altitude –ROC min @ some altitude (operating ceiling) –Balked landing –Climb Gradient (CGR) –Military Climb Requirements

26. Typical Performance Requirements  Maneuvering –Min turn rate (  ) – utility, agricultural, aerobatic, military ac –Min turn radius –Specific Excess Power (P s )  Airworthiness –Phoenix AZ 1990: airport closed for 3 days because of the heat; no civil ac could meet the takeoff field requirement

28. 5. Fuselage Design

30. 5. Cockpit Design

31. 6. Wing Design - Planform

32. 6. Wing Design - Airfoil

33. 6. High-Lift Devices

34. 6. Wing Design – lateral controls

36. 7. Empennage Design

38. 8. Landing Gear Design

39. 9. Weight & Balance

40. 9. C.G. Excursion Graph Location of Center of Gravity: From Nose: 2.36 ft From Ground: 1.6 ft

41. 10. Longitudinal Static Stability

42. 10. Directional Static Stability

43. L/D = 9.3 11. Drag Polar

44. 12. Final Design