Pressure loss during the first static firing test of the Aerojet solid rocket booster (SRB) for some models of the Lockheed Martin Atlas V fleet on 15 March has been blamed on burn-through of the unit's nozzle.
During the 95s test, exhaust leaked from the area of the nozzle, and thrust and pressure dropped Despite the problem, the test was regarded by Aerojet as a success, since it demonstrated a cold temperature start-up and use of a new inhibitor designed to test reduced lift-off dynamics.
Only one satellite, a 5t Inmarsat 4, is so far planned to fly on an Atlas V equipped with SRBs.
Source: Flight International