Key Upgrade Still up in the Air

A key safety system designed to prevent fuel tank explosions - like the kind that brought down TWA Flight 800 10 years ago off the coast of Long Island, killing all 230 aboard - has still not been installed on commercial airliners, officials with the National Transportation Safety Board said yesterday.

While significant safety improvements have been made to prevent similar explosions, the board's acting chairman, Mark V. Rosenker, said yesterday that the Federal Aviation Administration has dragged its feet in compelling the airlines to install the fuel tank inerting systems. The systems are designed to replace oxygen in the center fuel tanks with an inert gas, such as nitrogen, which can't cause an explosion.

Late yesterday, an association representing family members of those who died on Flight 800 called for a congressional investigation into why the systems have not been installed.

Risa Heller, a spokeswoman for Sen. Charles Schumer, said the senator would help. "They deserve answers," she said.

John Seaman, of upstate Clifton Park, who is chairman of Families of TWA Flight 800, lost his 19-year-old niece, Michele Becker. "The families tried to be patient. It's been 10 years since the loss of 230 lives. All of those folks died way too soon, and it was because of a known problem in the airlines that the NTSB has been trying to get the FAA to move on."

The NTSB is an independent oversight agency that investigates accidents on sea, air and on land. The FAA is a federal agency in charge of air safety regulations.

Most-wanted list

Rosenker said at a morning news conference that reduction of fuel tank flammability remains on the NTSB's "most wanted" list of safety improvements for commercial airliners.

The FAA defended its actions, which the airlines have been fighting.

"We are working as hard as we can," said John Hickey, the FAA's director of aircraft certification. "It was a very big rule and there were a lot of comments. Those comments have to all be addressed and analyzed. It is a costly rule and it puts the organizations in the business in a defensive mode."

Nonetheless, Rosenker said in an interview that he was frustrated. "Ten years is much too long, and this has been clearly resolvable," he said.

TWA 800, a Boeing 747, crashed on July 17, 1996, minutes after takeoff from Kennedy Airport on a flight to Paris. The NTSB determined the crash was caused by an explosion in the center wing fuel tank, resulting from ignition of the flammable fuel/oxygen mixture.

Richard Hammer of Glen Head lost his wife, Beverly, 59, and daughter, Tracy Anne, 28. "Something went dramatically wrong and potentially could happen again based upon their inaction," he said.

Plan to retrofit thousands

Last November, the federal government told airlines they needed to retrofit thousands of passenger aircraft with the inerting systems. The 152-page proposed rule issued by the FAA came after months of wrangling within the U.S. Department of Transportation, the FAA's parent agency, over the cost to the airlines - which could reach $1.6 billion.

After the rule was issued, the FAA had a public comment period, now closed. The agency has 16 months to analyze the comments, and the rule is not expected to be finalized this year. And, officials have speculated, the FAA is expected to give airlines from seven to 10 years to install the systems.

In a filing to the FAA, the powerful Air Transport Association, which represents major airlines, said the changes were unnecessary and too expensive, and said that new measures to prevent electrical sparks from igniting fumes are sufficient to prevent another catastrophe.

Rosenker said that the FAA has made significant progress in some areas. For example, there are now fleetwide inspections and reviews of fuel tank design. In addition, fuel pumps, fuel quantity indicating systems, in-tank wiring and operational procedures have been modified to make systems safer.

"The crash of TWA 800 was a watershed event for the air carrier industry," Rosenker said. "In the intervening years, a lot of thought and effort has been devoted to the issues raised by this accident, and the public is safer for it."

Safety's slow progress

Officials have had mixed success in getting airlines to fix the fuel vapor and wiring problems that brought down TWA flight 800.

(1) FUEL VAPORS

Problem: Fuel, combined with accumulating oxygen in the center tank, can ignite and explode. Officials are pushing airlines to install inerting systems to reduce oxygen in their planes' fuel tanks. (See diagram at left)

STATUS: None have been installed on commercial planes. Airlines say the changes are unnecessary and expensive. If officials finalize their ruling on this, airlines would likely have 7-10 years to make the fix.

(2) FAULTY WIRING

PROBLEM: Flight 800 investigators found that a spark from aging wiring likely caused an explosion in the center tank.

STATUS: Officials have made recommendations to address wiring problems. Inspections and maintenance of fuel pumps, wiring and other electrical components have been improved.

How inerting works

Air drawn in by plane's engines (A) is fed into inerting system. Inside, membranes separate nitrogen from oxygen (B) Oxygen is vented into atmosphere (C) and nitrogen, which is inert, is put into the center fuel tank (D). With less than 12 percent oxygen in the tank, fuel vapors are less likely to ignite. Inerting system can also be used with wing tanks.

SOURCE: National Transportation Safety Borard; Federal Aviation Administration; Boeing



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