Definition
A loss of lift caused by the formation of shock waves on the upper surface of a wing as airflow over the wing reaches the speed of sound. The shock waves disrupt the smooth airflow, causing it to separate from the wing surface, which destroys lift in much the same way a conventional aerodynamic stall does — but triggered by compressibility effects at high speed rather than by exceeding the critical angle of attack at low speed.
Plain English
A high-speed stall that happens when air moving over the wing goes supersonic and forms shock waves. Those shock waves break up the airflow, and the wing suddenly stops producing lift.
Context Anchor
Seen in high-speed aerodynamics, jet operations, and discussions of flying near an airplane’s high-speed limits.
Derivation
From shock wave (a sharp pressure discontinuity formed when airflow reaches the speed of sound) and stall (loss of lift). The name reflects the cause: it's a stall produced by shock waves, not by a high angle of attack.
Why Pilots Care
It can produce sudden buffeting and control loss during dives or high-speed maneuvers if speed is not reduced promptly.
Grounding Statement
Picture a very fast airplane where the air over the wing suddenly hits a pressure jump, stops flowing smoothly, and starts breaking away from the wing.
Intuition Check
Do not read shock stall as an electrical shock or a surprise event. Here, shock means a sudden pressure change in fast-moving air, and stall means the wing’s airflow has separated enough to reduce lift.
Example Sentence 1
As the aircraft approached its critical Mach number in the dive, the pilot eased back on the throttle to avoid a shock stall.
Example Sentence 2
Reducing power and lowering the nose allowed the airplane to recover from the shock stall before control effectiveness was fully lost.