The US Federal Aviation Administration (FAA) is considering a proposal that would require airlines to install new systems to further reduce fuel tank flammability on new and existing large passenger jets.
‘The FAA has issued more than 60 directives to eliminate fuel tank ignition sources, but we must do more,’ said FAA Administrator Marion C Blakey. ‘Our proposal would require a new type of equipment that would close the book on fuel tank explosions.’
Under the FAA’s Notice of Proposed Rulemaking, new fuel tank safety systems would have to be installed on Boeing and Airbus models whose air conditioning systems could cause heating of centre-wing fuel tanks. The new systems would reduce the flammability of fuel tank vapours on the ground and in flight.
According to the FAA, these new fuel tank systems work by replacing oxygen in the fuel tank with an inert gas, preventing the potential ignition of flammable vapours.
The FAA believes the new approach to both eliminating ignition sources and reducing fuel tank flammability could eliminate up to four accidents over the next 25 years. Centre wing fuel tank explosions, including the 1996 TWA 800 accident, have resulted in 346 fatalities.
In May 2002, the FAA unveiled a prototype inerting system that is said to be lightweight and uses no moving parts. Boeing used the FAA’s prototype to develop its own Nitrogen Generating System and plans to install the system on new production aeroplanes voluntarily beginning in 2005.
The FAA is considering requiring flammability reduction systems on new aeroplane models, such as the Airbus A-380 and Boeing 7E7. The FAA proposal would also prompt a retrofit of 3,800 Airbus and Boeing aeroplanes over seven years, with Boeing 737, Boeing 747, and Airbus A320 models to be retrofitted first. The total cost for retrofitting the US fleet is estimated at approximately $600 to $700 million.