Reliability
Graphite-Epoxy Motors have proven themselves to be reliable; however they are not infallible. On 17 January 1997, a Delta II (Delta 241) exploded 13 seconds after launch due to a rupture in a graphite-epoxy casing. The failure was a result of the casing having been damaged at some point in the transportation of the vehicle. The investigation team found the damage to the motor case to be caused by the stress induced by the supports which held the GEM during storage and transportation. When the motor ignited, the pressure inside the casing built up until the damaged casing could not hold in the pressure of the burning fuel and exploded, destroying the launch vehicle.
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