Stalltechnik

Stalltechnik refers to the study, interpretation, and application of techniques related to aircraft stalls, including their aerodynamic basis, recovery procedures, and design measures to prevent or manage stalls. In aviation, a stall occurs when the angle of attack of the wing exceeds its critical value, causing the airflow to separate from the upper surface. Lift decreases sharply while drag increases, and control effectiveness diminishes. The condition can lead to a loss of altitude or a spin if coupled with yaw and roll moments.

Causes and contributors include high angle of attack at low airspeed, unfavorable weight and balance, flap or gear configurations, turbulence, and abrupt control inputs. Stall behavior varies with aircraft type, configuration, and loading; common variants include clean stalls (no flaps), approach-to-stall conditions, and full or aggravated stalls.

Recovery procedures emphasize prompt and coordinated action: reduce angle of attack by pushing the nose down, apply power to regain airspeed, and level the wings with coordinated rudder and aileron inputs. Avoid abrupt or excessive control movements and ensure full control authority is restored before resuming normal flight.

Training and safety play a central role. Stall awareness is taught in flight schools, often with stick-shaker or stick-pusher systems and supervised stall practice to establish proper recognition and reaction. Spin training may be included where appropriate.

Design and technology aim to delay stall or ease recovery. Features include wing washout, leading-edge devices (slats), cuffing, vortex generators, stall strips, and improved boundary-layer control. Modern aircraft also use angle-of-attack sensors and stall-warning systems to enhance early detection and response.