1980 Damascus Titan missile explosion

The Damascus Titan missile explosion was an incident in which liquid fuel in a LGM-25C Titan II intercontinental ballistic missile exploded at missile launch facility Launch Complex 374-7 in Van Buren County farmland just north of Damascus, Arkansas, on September 18–19, 1980. The facility was one of the 18 silos in the command of the 308th Strategic Missile Wing (308th SMW), specifically one of the 9 silos within its 374th Strategic Missile Squadron (374th SMS), at the time of the explosion.

On the evening of September 18, 1980, at about 6:30 p.m., 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 Air Force Base's Launch Complex 374-7. Incorrectly using a large (25 lb (11 kg) and 3 feet (0.9 m) long) socket wrench, they accidentally dropped an 8 lb (3.6 kg) socket, which fell about 80 feet (24 m) before hitting a thrust mount and piercing the skin on the rocket'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.

Eventually, the missile combat crew and the PTS team evacuated the launch control center, while military and civilian response teams arrived to tackle the hazardous situation. There was concern for a possible collapse of the now empty first-stage fuel tank, which could cause the rest of the missile to fall and rupture, allowing the oxidizer to contact the fuel already in the silo.

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