Volume 5, Issue 2 (March 1977)
Simulating Rain Impact Damage to Supersonic Missile Radomes
A test simulating the rain impact damage to two ceramic missile radomes traveling at supersonic speeds is described. A water-jet gun has been developed which fires a short burst of water at speeds up to 5000 ft/s (1524 m/s). This gun was used to simulate the impact of raindrops on the radomes. Equations are given relating the crater volume and area of a single jet impact to the energy of the jet. Then equations are given which express the cumulative damage as a function of impact angle, drop size distribution, velocity, and rain field length and intensity. A computer code has been written to solve these equations. The computer code gave results that agreed well with an actual rocket sled test. The code was used to predict the damage for a new set of conditions, and the water-jet gun was used on full-scale radomes to simulate the predicted rain impact damage.