Apollo 15 main-parachute failure

In the investigation of the failure of one of the three main parachutes of the Apollo 15 spacecraft, which collapsed at approximately 1825 meters after operating properly from deployment at 3050 meters, three conditions considered to be possible causes of the failure were produced. The suspect conditions were the proximity of the forward heat shield that passed the spacecraft at approximately 1825 meters, the dumping of the reaction control system hypergolic propellants at approximately 1825 meters, and the failing of a riser link found on a recovered parachute. (The failed parachute was not recovered). The remaining two parachutes functioned as planned and averted a catastrophic failure. The conclusions concerning the cause of the failure are discussed.