This picture show the results of a foam strike test on a Reinforced Carbon-Carbon (RCC) panel. The RCC forms the leading edge of the shuttle wing. A 1.7 pound piece of foam struck the Colombia at 500 MPH on an RCC panel on the left wing, probably causing damage similiar to this a 16 inch hole. Superheated plasma penetrated the wing during re-entry and melted the underlying aluminum structure, ultimately causing a structural failure and the destruction of the spacecraft.