Cargo carriers and manufacturers oppose a proposed fix for a problem the NTSB says likely caused the in-flight explosion of TWA Flight 800 near Long Island, N.Y., in 1996. That event killed all 230 aboard. The FAA has applied a fix for passenger aircraft and now wants to apply changes to cargo jets. The NTSB has estimated that the problem (faulty wiring in a fuel tank) would cause similar events every four years. And in 2001 a 737-400 suffered an explosion while on the ramp at Bangkok, and in 2006 a 727-200 suffered an explosion while on the ground in India. But Boeing says the risk for cargo operators is "less than extremely improbable," the Seattle Times reported Friday. The manufacturer has found support from Airbus, the airline trade group A4A, UPS and FedEx. Meanwhile, the clock is ticking in more ways than one.
The NTSB's estimate does not include certain safety measures already put in place across much of the affected fleet. And the remaining service life of affected cargo jets may be running out. Boeing estimates that because of that, the probability of an accident is "unlikely to occur in the operational life" of the affected cargo fleet. That fleet is currently made up of roughly 352 cargo aircraft flying in the U.S. Timing might not be the only concern. The FAA's proposed fix would require Boeing to change certain fuel-tank wiring. It estimates the cost of that fix at $100,000 to $200,000 per airplane. Boeing says the figure would be much higher and has instead offered a different solution -- fitting the jets with nitrogen-generating systems that displace flammable vapors. The system is fitted to all Boeing aircraft made today. But that solution would cost carriers $323,000 per aircraft to retrofit. Carriers have balked at the figure and have asked the FAA to run a thorough cost-benefit and risk analysis prior to requiring any mandatory fix. If the FAA takes them up on it, most of the affected fleet could be retired before new regulations roll out.