August 22, 2000

TWA Flight 800 Crash Still a Mystery

WASHINGTON ––  Four years after an explosion destroyed TWA Flight 800 and 
killed all 230 aboard, federal investigators are taking what they hope will be a 
final look into the mystery of what happened.

The National Transportation Safety Board opens a two-day meeting Tuesday to 
review the evidence collected in its investigation.

Speculation has ranged from a spark caused by electrical wiring, to turbulence 
caused by another aircraft, bombs, even a missile. There has even been a 
suggestion that the answer may never be known.

What has become apparent in the long, costly probe is the Boeing 747 was 
destroyed by an explosion that originated in its central fuel tank on July 17, 1996, 
shortly after takeoff on a New York to Paris flight.

Even without knowing what ignited the Flight 800 blast, the investigation has 
led to extensive changes in design and regulation that are expected to improve 
safety in the years to come.

Shortly after the crash, investigators determined that the plane's almost-empty 
center fuel tank exploded, but they have not settled on the source of ignition.

One possibility that has been widely discussed is electrical wiring passing 
near or through the fuel tank.

The plane had spent considerable time waiting for takeoff on the runway, and 
air conditioners located beneath the fuel tank could have caused it to overheat.

Since the focus shifted toward the fuel tank, the Federal Aviation 
Administration has ordered 37 corrective actions for commercial airliners. Among them are 
replacing sharp-edged fuel probes that might damage wires, keeping pumps idle 
unless they are submerged in fuel, installing protective sleeves on wiring in 
tanks and developing electronic devices to suppress power surges in wiring.

Beth Erickson, head of aircraft certification for the FAA, said the agency has 
reviewed the history of fuel tanks on 10,000 commercial and noncombat military 
planes and found few problems.

Industry also participated, reporting a week ago that a three-year study 
concluded airline fuel tanks are safe.

The Air Transport Association, the airline industry's trade association, said 
more than 100,000 work hours were spent inspecting 990 aircraft operated by 160 
airlines as part of the program.

Erickson said the FAA determined that three factors are needed for a fuel-tank 
explosion: flammable vapors, oxygen and an ignition source.

Changes are being made in all three areas: eliminating sparks; inerting, or 
filling the empty area of fuel tanks with nitrogen rather than allowing in air 
that contains potentially flammable oxygen; reducing vapors by keeping tanks 
fuller; cooling fuel tanks; and changing fuel formulas.

Early in the investigation the possibility of a bomb led the government to 
tighten security procedures. Investigators have not reported evidence of 
explosives, either from a bomb or a missile.

Eyewitness reports of streaks of light seen nearby on the night of the crash 
have continued to plague investigators and to fuel conspiracy theories. That led 
the NTSB to go so far as to test-fire missiles to determine just what witnesses 
might have been able to see on the night of the crash.

This month a group of skeptics in Springfield, Mass., sued the government 
seeking details of its inquiry into the crash, including radar data and information 
on material found with some of the victims' bodies.

Retired Navy pilot William Donaldson, a vocal critic of the investigation, 
issued a statement Monday contending that the government is determined to cover up 
the cause of the crash.