Max Q

In the aviation and space technology called Max Q the point at which, reached ( in the spatial and temporal sense), the aerodynamic load on a flying object that moves in areas with large variations in air density maximum. In addition to the separation of the outer tank or rocket stages Max Q is one of the critical points in time during a rocket launch.

The stress is described by the dynamic pressure

With the density ρ ( " Rho " ), and the velocity v.

Application in space

After the launch of a missile from the surface, the velocity v increases because of the acceleration, while the air density ρ drops with increasing height. At a specific combination of speed and density of the force acting on the flying object is at a maximum back pressure, which corresponds to the point Q Max.

At the launch of the space shuttle is Max Q and reaches the greatest burden of the structure after about one minute flight duration at an altitude of about 11,000 m. At the start of the Saturn V moon rocket Max Q was a little later at a higher altitude, from Apollo 8, this was after 79 seconds at 13,400 m. When entering the Apollo capsule, the maximum dynamic pressure was greater than at the start of the Saturn V. In contrast, the Space Shuttle generates already at moderate back pressure enough aerodynamic lift to delay the descent into denser air masses.