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Modern Design Concept. Chapter 10. Aerodynamic Research Contributions. Propulsion Structural Design Monocoque structure Optimum location for the engine nacelles. Light Planes Then & Now.
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Modern Design Concept Chapter 10
Aerodynamic Research Contributions • Propulsion • Structural Design • Monocoque structure • Optimum location for the engine nacelles
Light Planes Then & Now • Most light airplane manufacturers used only very low powered engines and applied them to tube and fabric frames. • Very light sport plane with little real utility • Beechcraft had the first truly modern light airplane, figure 8-14 p.234 • 175mph on only 185 hp
Light Planes Piston engines- dominated general aviation Due to lower cost & fuel efficiency Drag clean up by improving efficiency of airflow- (wheel fairings)
Canards • Forward mounted horizontal tail arrangement • Leading proponents of canard is Burt Rutan • Figure 10-7 p. 279
Canard • PROS • It provides additional lift in the positive direction while performing its primary task of balancing the wing pitching moment • Higher L/D overall airplane • Canard is out of wing downwash; so efficient at high angle of attack
Canard • CONS • The canard surface will increase in lift and nose-up moment, with increased angle of attack destabilizing • Stability can be provided by the wing, but this requires that the wing always behind the CG in order to give a nose-down moment at increased angle of attack
Canard • CONS • Center of gravity travel is limited • Horizontal surface mounted forward; the vertical tail must always be aft of the CG
Effective Aspect Ratio Devices • Tip Shape Effect • Endplates • Winglets • Swept wing
Quiz on Chapter 10 Please take out a sheet of paper Include today’s date and your name
Quiz on Chapter 10 • List one pro and one con of the canard.