An Air China Boeing 737 Next Generation airliner recently pulled up to the gate, caught fire, and moments after the passengers deplaned through emergency exits, the center fuel tank exploded and destroyed the aircraft.
Had the explosion occurred just minutes before, all 152 passengers would most likely have been killed. The TWA 800 explosion brought home a well-known fatal flaw in transport category aircraft – large fuel tanks harbor fuel vapors that can explode and kill people. The problem has been well known for 45 years. The military long ago addressed it by putting fire suppression safeguards in large aircraft fuel tanks. Nitrogen inerting of the fuel tank is the preferred method and is effective, although passing cabin air through the tanks to lean the air and purge fuel molecules is another method.
Nitrogen inerting systems are supposed to be installed in new aircraft but either the system didn’t work, the aircraft didn’t have one, or other factors that need further investigation allowed an explosion to occur. The bottom line is simple. FAA predictions that center fuel tank explosions would be unlikely, with only four predicted over the next fifty years are obviously bogus, like all other FAA predictions. Inerting the fuel tanks of all transport category airplanes is vital unless we are prepared to assume the human and economic costs of hundreds dead.
Today, new fuel tank inerting systems that manufacture their own nitrogen from air weigh only a few hundred pounds. They can be retrofitted and eliminate this problem that has already taken a thousand lives. When technology is available to prevent death in aviation, it is immoral to allow bureaucratic inaction and industry stonewalling to assume this risk flight after flight. The FAA needs to act now!
Arthur Alan Wolk
August 2007