Aerodynamics of Flight

Rudder Inboard wing Elevator Tab Outboard wing Stabilizer Foreflap Midflap Inboard flap Aftflap Flight spoilers Ground spoiler Outboard flap Aileron Tab Landing Flaps Aileron Leading edge slats Inboard wing Leading edge flaps 737 Control Surfaces Outboard wing Control tab Stabilizer Inboard aileron Elevator Leading edge flaps Control tab Aileron Upper rudder Takeoff Flaps Anti-balance tabs Lower rudder Foreflap Midflap Aftflap Vortex generators Pitot tubes Inboard wing Ground spoilers Inboard flaps Outboard wing Flight spoilers Outboard flap Leading edge slat Balance tab Leading edge flap Outboard aileron Slats Fence Aileron 727 Control Surfaces Flaps Retracted Figure 5-71. Control surfaces. differential type, they extend further on one side and retract around the wing leading edge. The airflow tends to tear loose on the other side. If they are the non-differential type, they rather suddenly from the upper surface at a moderate AOA. extend further on one side but do not retract on the other side. To utilize trailing edge flaps, and thus increase the C , L-MAX When fully extended as speed brakes, the non-differential the wing must go to a higher AOA without airflow separation. spoilers remain extended and do not supplement the ailerons. Therefore, leading edge slots, slats, and flaps are used to improve the low-speed characteristics during takeoff, climb, To obtain a smooth stall and a higher AOA without airflow and landing. Although these devices are not as powerful as separation, the wing’s leading edge should have a well- trailing edge flaps, they are effective when used full span in rounded almost blunt shape that the airflow can adhere to combination with high-lift trailing edge flaps. With the aid at the higher AOA. With this shape, the airflow separation of these sophisticated high-lift devices, airflow separation is starts at the trailing edge and progresses forward gradually delayed and the C is increased considerably. In fact, a L-MAX as AOA is increased. 50 knot reduction in stall speed is not uncommon. The pointed leading edge necessary for high-speed flight results in an abrupt stall and restricts the use of trailing edge flaps because the airflow cannot follow the sharp curve 5-50