Static electricity is the latest theory being examined by investigators seeking the cause of the TWA Flight 800 explosion, a safety board official said Saturday.
“This is a possibility but it’s not the only one,” said the National Transportation Safety Board official who spoke on condition of anonymity. “It’s a very possible source but we are by no means certain.”
The investigation of the July 17 explosion has been a process of elimination. Investigators say they have not ruled out the possibility that the Paris-bound plane was downed by a bomb, missile or a mechanical malfunction after it left Kennedy Airport.
Investigators believe the nearly empty center fuel tank on the Boeing 747 exploded but haven’t pinpointed what ignited the blast.
As a result of its probe, the NTSB on Friday urged the Federal Aviation Administration to adopt rules that would improve the safety of fuel tanks, preventing possible explosions caused by heat, sparks or static electricity.
The static electricity theory centers on the possibility that static built up around a pipe that carries fuel through but not into the center fuel tank. Just as static can build around a pipe in a house, it can also form around a pipe in an airplane.
The static could have been created by fuel spray that might have escaped through a pinhole rupture in the fuel pipe into the nearly empty center fuel tank, igniting vapors capable of exploding if their temperature had risen to at least 100 degrees.
Another possibility is that an electrical spark might have jumped out of a loosened joint in the pipe, touching off the explosion when the spark connected with the hot vapors.