...When Commercial Aircraft Explode
Besides the TWA accident, which resulted in 346 deaths, two fuel-tank explosions occurred in Boeing 737s in Asia while the aircraft were on the ground. In March 2001, a Thai Airways 737-400 exploded while sitting on a hot ramp at Bangkok's domestic airport, and in May 1990, a center-wing fuel tank of a Philippine Airlines 737-300 exploded. The FAA's explosion-prevention device dumps oxygen into the atmosphere and pumps nitrogen into the fuel tanks. The extra nitrogen cuts oxygen content by almost half, making combustion of fuel vapors virtually impossible. The systems need about $14,000 worth of maintenance every year. They weigh less than 200 pounds.