TWA crash investigators to begin tests
January 7, 1997
From Correspondent Christine Negroni
NEW YORK (CNN) -- Confounded by a lack of evidence, investigators probing the crash of TWA Flight 800 are reconsidering a well-known aviation fact and a conversation in the cockpit shortly before the crash, wondering if they are clues to the explosion aboard the aircraft.
On the voice cockpit recorder, the 747's engineer is heard beginning the process of cross-feeding, or moving fuel through various fuel tanks.
The National Transportation Safety Board plans to begin tests soon to see how much static electricity could have been created by cross-feeding.
The idea that electrostatic spark might have ignited the plane's center wing is considered the best explanation for the explosion.
Fuel leak may have caused static
It is common knowledge among aviation experts that static electricity is generated by the movement of fuel both in refueling and as it moves to the engines in flight.
Boeing, the manufacturer of the 747, says that electrostatic charges are dissipated through the frame of the aircraft through a form of grounding.
A number of independent crash investigators agree this design makes it practically impossible that a spark could have gotten into the plane's nearly empty fuel tank.
There is one way, however, that a spark could have been created in the tank, according to several investigators.
Tests changed after Boeing objected
If fuel was leaking at any of the seams along the cross-feed line, or through a hole in the pipe, the spraying fuel could have created a spark in the tank. And the investigators know the tank was filled with volatile fumes.
This will be the second time the NTSB has tried to replicate various cross-feeding scenarios. The first tests were scuttled when Boeing objected to the way they were to be conducted.
Static electricity is a fleeting phenomenon. Investigators say creating and measuring it in the lab might be the only way to determine what role, if any, it played in the crash.
Related sites:Note: Pages will open in a new browser window
External sites are not endorsed by CNN Interactive.
© 1997 Cable News Network, Inc.
Terms under which this service is provided to you.