The incident began with a fuel leak at 6:30 p.m. on September 18, and culminated with the explosion at around 3:00 a.m. on September 19, ejecting the warhead from its silo.[2] The warhead landed a short distance away and no radioactive material was lost.
Launch complex
Launch Complex 374-7 was located in Bradley Township, Van Buren County farmland just 3.3 miles (5.3 km) NNE of Damascus, and approximately 50 miles (80 km) north of Little Rock.[3][4]
At 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 of a USAF Titan II missile at Little Rock AFB's Launch Complex 374-7. One of the workers, Airman David P. Powell, had brought a ratchet wrench – 3 ft (0.9 m) long weighing 25 lb (11 kg) – into the silo instead of a torque wrench, the latter having been newly mandated by Air Force regulations.[5] Powell later claimed that he was already below ground in his safety suit when he realized he had brought the wrong wrench, so he chose to continue rather than turn back.[5] The 8 lb (3.6 kg) socket fell off the ratchet and dropped approximately 80 feet (24 m) before bouncing off a thrust mount and piercing the missile's skin over the 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, dinitrogen tetroxide, such that they spontaneously ignite upon 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 nine-megaton W-53 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. Lieutenant General Lloyd R. Leavitt Jr., the Vice Commander of the Strategic Air Command, commanded the effort to save the launch complex.[6] There was concern for the possible collapse of the now-empty first-stage fuel tank, which could cause the rest of the 8-story missile to fall and rupture, allowing the oxidizer to contact the fuel already in the silo.
Explosion
Early in the morning of September 19, a two-man PTS investigation team consisting of Senior Airman David Lee Livingston and Sergeant Jeff K. Kennedy entered the silo. Because their vapor detectors indicated an explosive atmosphere, the two were ordered to evacuate. The team was then ordered to reenter the silo to turn on an exhaust fan. Livingston reentered the silo to carry out the order and shortly thereafter, at about 3:00 a.m., the hypergolic fuel exploded—likely due to arcing in the exhaust fan. The initial explosion catapulted the 740-ton silo door away from the silo and ejected the second stage and warhead. Once clear of the silo, the second stage exploded. The W53thermonuclear warhead landed about 100 feet (30 m) from the launch complex's entry gate. Its safety features prevented any loss of radioactive material or nuclear detonation.[7][8]
Aftermath
Livingston died at the hospital, and 21 others in the immediate vicinity of the blast sustained various injuries; Kennedy struggled with respiratory issues from inhaling oxidizer but survived. Livingston was posthumously promoted to staff sergeant.[2] The entire missile launch complex was destroyed.[2]
At daybreak, the Air Force retrieved the warhead,[9][10] which was returned to the Pantex weapons assembly plant.[11]
The launch complex was never repaired. Pieces of debris were taken away from the 400 acres (1.6 km2) surrounding the facility, and the site was buried under a mound of gravel, soil, and small concrete debris. The land is now under private ownership.[2][12] The site was listed on the National Register of Historic Places on February 18, 2000.[2]
Kennedy, initially praised as a hero, later received an official letter of reprimand for his first entry into the complex, as it later transpired that he had disregarded an order to stay away.[5]
^O'Hehir, Andrew (September 14, 2016). "The night we almost lost Arkansas – a 1980 nuclear Armageddon that almost was". Salon. Retrieved November 18, 2020. On a September night 36 years ago, we nearly lost Arkansas. Some people may regard that as a mixed blessing, even now – Bill Clinton and his wife, then the governor and first lady of that state, were less than 50 miles away in Little Rock, at the Arkansas Democratic Convention. If the Titan 2 intercontinental ballistic missile, or ICBM, that exploded inside its silo in Damascus, Arkansas, had detonated its nuclear warhead, both the Clintons and Vice President Walter Mondale (also attending the convention) would have been dead within minutes.