Damascus Titan missile explosion

The Damascus Titan missile explosion was an incident in the United States in 1980 in rural Arkansas. Liquid fuel in a U.S. Air Force LGM-25C Titan II intercontinental ballistic missile exploded at a missile launch facility on September 19, 1980. It occurred at Launch Complex 374-7 in Van Buren County farmland just north of Damascus, approximately fifty miles (80 km) north of Little Rock.

The Strategic Air Command facility of Little Rock Air Force Base was one of eighteen silos in the command of the 308th Strategic Missile Wing (308th SMW), specifically one of the nine silos within its 374th Strategic Missile Squadron (374th SMS), at the time of the explosion.

Around 6:30 p.m. CDT on Thursday, September 18, 1980, two airmen from a propellant transfer system (PTS) team were checking the pressure on the oxidizer tank on a USAF Titan-II missile at Little Rock AFB's Launch Complex 374-7. Due to time constraints when going into the silo, a previously acceptable ratchet and socket (3 ft (0.9 m), 25 lb (11 kg)) was taken instead of the newly mandated torque wrench. The 8 lb (3.6 kg) socket was accidentally dropped approximately 80 feet (24 m) before hitting a thrust mount and piercing the skin on the missile's first-stage fuel tank, causing it to leak a cloud of its aerozine 50 fuel.

Aerozine 50 is hypergolic with the Titan II's oxidizer, nitrogen tetroxide; i.e., they spontaneously ignite on contact with each other. The nitrogen tetroxide is kept in a second tank in the rocket's first-stage, directly above the fuel tank and below the second-stage and its 9-megaton W53 nuclear warhead.

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