Plain English Meaning

When a fast jet gets close to the speed of sound, the airflow over the wing changes in a way that pushes the nose down on its own. If the pilot doesn't correct it, the aircraft tries to dive even faster, which makes the problem worse.

Full Definition

An uncommanded nose-down pitching tendency that occurs when an aircraft approaches or exceeds its critical Mach number. As airflow over the wing reaches supersonic speed, shock waves form and disrupt the lift distribution, shifting the wing's center of lift rearward. This rearward shift creates a strong nose-down pitching moment that, if uncorrected, can drive the aircraft into a steeper dive and a further increase in , worsening the .