7 Flight Mystery and Aerodynamic Principles
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Fig. 7.90 Counter-rotating propeller engine
Fig. 7.91 European A400M propeller transporter
attack, at which point it can fly smoothly at a small angle of attack. However,
when taking off or landing, because the speed of the aircraft is small, in order
to achieve the required lift, on the one hand, the angle of attack of the aircraft
needs to be enlarged, on the other hand, the airflow bypassing the aircraft is
in the acceleration and deceleration zone, and the aircraft is near the ground.
At this time, the control is more difficult than the cruise, and the aircraft
accident rate is much higher than the cruise state. According to statistics, the
accident rate of the aircraft in the takeoff and landing state can reach about