Pressure measurements on a Mach 5 sabot during discard

An experimental program has been conducted in a Mach 5 airflow to obtain surface pressures in the scoop and on the underside of a sabot at different stages of the discard process. The data are needed to validate computer codes used for predicting the trajectory of the sabot during discard and to aid in the design of minimum-interference sabots. Because of wind-tunnel size constraints, the tests were carried out using a model with one sabot petal. The remaining sabot petals were modeled by using splitter plates as symmetry planes, Assessment of the data indicates that the complex flow structure between the sabot and projectile is simulated using this approach. Because of the complex shock-shock and shock-boundary-layer interactions, the pressure distributions on the sabot underside have very distinctive shapes with large maxima; if a code can locate these maxima and predict their magnitudes reasonably well, then the integrated forces and moments (which determine the sabot trajectory) should be modeled reasonably accurately. The current data should prove useful in that regard.