Boeing says design not key in TWA crash report

SYDNEY, Aug 24 (Reuters) - Boeing Co (NYSE:BA - news) said on Thursday it believed a National Transportation Safety Board (NTSB) report into the explosion of TWA Flight 800 pointed to a potential problem with maintenance, not design flaws.

``The NTSB pointed out a potential problem, not a design problem, primarily around maintenance and the way maintenance is done,'' chief executive officer Phil Condit told reporters in Sydney via satellite.

``We have in fact taken all the recommendations that have come out of the NTSB and we have actively supported it,'' Condit said.

All 230 people aboard the New York-to-Paris flight were killed when the Boeing 747 blew up off Long Island on July 17, 1996, 14 minutes after takeoff from Kennedy International Airport.

Capping the costliest investigation of its kind, the five-member NTSB board said on Wednesday the accident's probable cause was an explosion in the plane's centre wing fuel tank caused by ignition of flammable vapours.

NTSB Chairman Jim Hall said the accident was caused by a chain of events ``set in motion years before by the manufacturer's and the FAA's design and certification policy.''

The safety board faulted the ``design and certification concept that fuel tank explosions could be prevented solely by precluding all ignition sources'' -- a swipe at both Boeing and the Federal Aviation Administration, which regulates the aviation industry.

``Boeing's design practice of permitting parts less than 3 inches (7.6 cm) in any direction to be electrically unbonded may not provide adequate protection against potential ignition hazards as a result of static electricity generated by lightning and other high-energy discharges,'' the board ruled.

The board issued four new safety recommendations in addition to those that had already led to some 40 FAA safety directives growing out of TWA 800.

It urged the FAA to examine the bonding of components in fuel tanks to eliminate potential ignition sources; to review wiring systems of all U.S.-certified aircraft and require any changes needed to ensure ``adequate separation;'' to work to eliminate the ignition risk posed by silver-sulfide deposits inside fuel tanks; and to act on training issues related to the repair of potentially unsafe wiring.

Boeing had told the safety board it found nothing to support the idea that a ``specific electrical system or component of the 747-100 fuel quantity indicating system ignited a fuel/air explosion.''

``None of the recovered fuel system components inspected and analysed showed any evidence of being the ignition source that initiated the accident,'' Boeing said in an April 28 submission after its own $32 million investigation.