Stalling & Spinning Flashcards
Define a stall.
A stall is a condition when the aircraft is unable to maintain level flight due to a reduction of lift.
What happens when the aerofoil moves beyond the critical angle of attack.
The separation point moves forward, leaving a larger turbulent wake as the airflow closest from to the top of the aerofoil separates away. This results in a rapid reduction in lift. The COP also moves rearward, resulting in a pitch down.
What are the factors affecting stall speed?
Weight, Increases stall speed
Ice/contamination, promotes separation of airflow over wing, increases stall speed.
Load Factor, Increases stall speed.
Power, Decreases stall speed, due to vertical component of thrust.
Slats/Slots & Flaps, Decreases stall speed by increasing CL and providing more lift for a given AOA.
What is a spin?
A condition of stalled flight where the aircraft is in an advanced stage of autorotation and follows a helical descent around a vertical axis.
What is autorotation?
Autorotation is when the aircraft is experiencing a cycle of auto roll - yaw and roll.
How does the incipient stage of a spin occur?
Incipient stage occurs due to one wing of the aircraft more deeply stalled than the other. This causes the aircraft to wing drop, producing more drag and forcing the aircraft to yaw in the direction of the initial roll.
What is the primary difference between a spin and a spiral dive?
During a spin the aircraft wings are stalled at a high AOA.
During a spiral dive the wings are not stalled and the aircraft is experiencing a high airspeed with lower AOA.
