Mach tuck
![Shock wave above wing moves rearwards as aircraft speed approaches Mach 1](/Images/godic/202501/25/Transonic_flow_patterns.svg2702.png")
![The P-38 Lightning gave Lockheed engineers a great deal of initial design trouble because it was so fast that it was the first American aircraft to experience compressibility and Mach tuck.](/Images/godic/202501/25/Lockheed_P-38J_Lightning_-_12702.jpg")
Mach tuck is an aerodynamic effect whereby the nose of an aircraft tends to pitch downward as the airflow around the wing reaches supersonic speeds; the aircraft will first experience this effect at significantly below Mach 1. This speed is known as the critical Mach number of the wing.