【正文】 an airplane into a turn. 正確答案：A (25)Which is a purpose of ground spoilers A．Reduce the wings lift upon landing B．Aid in rolling an airplane into turn. C．Increase the rate of descent with out gaining airspeed. 正確答案：A (26)What is the purpose of a control tab? A．Move the flight controls in the event of manual reversion. B．Reduce control forces by deflecting in the proper direction to move a primary flight control. C．Prevent a control surface from moving to a fulldeflection position due to aerodynamic forces. 正確答案：A (27)Which is a purpose of wingmounted vortex generators? A．Reduce the drag caused by supersonic flow over portions of the wing B．Increase the onset of drag divergence and aid in aileron effectiveness at high speed C．Break the airflow over the wing so the stall will progress from the root out to the tip of the wing 正確答案：A (28)What is the purpose of a servo tab？ A．Move the flight controls in the event of manual reversion. B．Reduce control forces by deflecting in the proper direction to move a primary flight control. C．Prevent a control surface from moving to a fulldeflection position due to aerodynamic forces. 正確答案：B (29)What is the purpose of an elevator trim tab? A．Provide horizontal balance as airspeed is increased to allow handsoff flight. B．Adjust the speed tail load for different airspeeds in flight allowing neutral control forces. C．Modify the downward tail load for various airspeeds in flight eliminating flightcontrol pressures. 正確答案：C (30)Which direction from the primary control surface does a servo tab move? A．Same direction. B．Opposite direction. C．Remains fixed for all positions. 正確答案：B (31)Which direction from the primary control surface does an antiservo tab move? A．Same direction. B．Opposite direction. C．Remains fixed for all positions. 正確答案：A (32)Which direction from the primary control surface does an elevator adjustable trim tab move when the control surface is moved? A．Same direction. B．Opposite direction. C．Remains fixed for all positions. 正確答案：C (33)What is the reason for variations in geometric pitch along a propeller or rotor blade? A．It permits a relatively constant angle of attack along its length when in cruising flight. B．It prevents the portion of the blade near the hub or root from stalling during cruising flight. C．It permits a relatively constant angle of incidence along its length when in cruising flight. 正確答案：A (34)Which flight conditions of a large jet airplane create the most severe flight hazard by generating wingtip vortices of the greatest strength? A．Heavy, slow, gear and flaps up. B．Heavy, slow, gear and flaps down. C．Heavy, fast, gear and flaps down. 正確答案：A (35)Wingtip vortices created by large aircraft tend to A．Sink below the aircraft generating the turbulence. B．Rise from the surface to traffic pattern altitude. C．Accumulate and remain for a period of time at the point where the takeoff roll began. 正確答案：A (36)Which statement is true concerning the wake turbulence produced by a large transport aircraft? A．Vortices can be avoided by flying 300 feet below and behind the flight path of the generating aircraft. B．The vortex characteristics of any given aircraft may be altered by extending the flaps or changing the speed. C．Wake turbulence behind a propellerdriven aircraft is negligible because jet engine thrust is a necessary factor in the formation of vortices. 正確答案：B (37)If you take off behind a heavy jet that has just landed, you should plan to lift off A．prior to the point where the jet touched down. B．beyond the point where the jet touched down. C．a(chǎn)t the point where the jet touched down and on the upwind edge of the runway.正確答案：B (38)How does the wake turbulence vortex circulate around each wingtip? A．Inward, upward, and around the wingtip. B．Counterclockwise when viewed from behind the aircraft. C．Outward, upward, and around the wingtip. 正確答案：C (39)Hazardous vortex turbulence that might be encountered behind large aircraft is created only when that aircraft is A．Developing lift B．Operating at high airspeeds C．Using high power settings正確答案：A (40)It is the responsibility of the pilot and crew to report a near midair collision as a result of proximity of at least A．500 feet or less to another aircraft. B．50 feet or less to another aircraft. C．1,000 feet or less to another aircraft.正確答案：A (41)To allow pilots of intrail lighter aircraft make flight path adjustments to avoid wake turbulence, pilots of heavy and large jet aircraft should fly A．below the established glidepath and slightly to either side of the oncourse centerline. B．a(chǎn)bove the established glidepath and slightly downwind of the oncourse centerline. C．on the established glidepath and on the approach course centerline or runway centerline extended.正確答案：C (42)How can the pilot increase the rate of turn and decrease the radius at the same time? A．Steepen the bank and increase airspeed. B．Steepen the bank and decrease airspeed. C．Shallow the bank and increase airspeed. 正確答案：B 43)How can turbulent air cause an increase in stalling speed of an airfoil? A．An abrupt change in relative wind. B．A decrease in angle of attack. C．Sudden decrease in load factor. 正確答案：A (44)What is the relationship of the rate of turn with the radius of turn with a constant angle of bank but increasing airspeed? A．Rate will decrease and radius will increase. B．Rate will decrease and radius will decrease. C．Rate and radius will increase. 正確答案：A (45)Which condition would INITIALLY cause the indicated airspeed and pitch to increase and sink rate to decrease? A．Sudden increase in a headwind ponent. 18