Max Q

The max Q condition is the point when an aerospace vehicle's atmospheric flight reaches maximum dynamic pressure. This is a significant factor in the design of such vehicles because the aerodynamic structural load on them is proportional to dynamic pressure. This may impose limits on the vehicle's flight envelope.

Dynamic pressure, q, is defined mathematically as

Q=1/2PV^2

>The Q fx()

https://en.wikipedia.org/wiki/Max_q