Stall (flight)#Deep stall

Deep Stall ( German: deep demolition ) is the critical flight condition of an aircraft, in which simultaneous stall (English stall ) on the wings of the elevator is not in the air stream and therefore also can not contribute more to the control. A deep stall usually leads to loss of control and therefore at high altitude crash of the aircraft, as the stalled flight condition can not be changed by the elevator.

Affected by this effect are usually aircraft with a T-tail (elevator above the rudder ). To counter the effect, so-called stick - pusher were introduced: automatics, the press the control column forward when the angle of attack reaches a limit. Virtually all early passenger aircraft with a T-tail were affected by the effect or had to be redesigned accordingly, the BAC 1-11 and the Ilyushin Il- 62.

Deep stall is sometimes referred to as super stable.