The US Federal Bureau of Investigation (FBI) has closed its 16-month criminal probe into the crash of Trans World Airlines Flight 800, saying that it revealed no evidence of a criminal act.

As a result, the investigation of the loss of the TWA Boeing 747-100 becomes the sole responsibility of the US National Transportation Safety Board (NTSB), which has been investigating the accident in parallel with the FBI. The 747 crashed into the sea on 17 July 1996 off Long Island, New York, shortly after take-off bound for Paris, killing all 230 people on board.

Although mechanical failure is cited as the most likely cause of the fatal accident, the Safety Board still does not know why the centre-wing tank exploded, and have not located the ignition source.

The FBI went to great lengths to dispel a theory that a missile destroyed the 747. It released a video simulation of the flight's final minutes off the coast of Long Island, New York, which showed how burning jet fuel was mistaken by witnesses for a streaking missile.

The FBI says that its probe will remain dormant unless new evidence of a criminal act is uncovered. The Bureau had originally hinted that terrorism was to blame, but, by late last year, the FBI's theory began to unravel. It said that no warship or aircraft in the area had fired a missile at the 747.

The NTSB will hold a week-long hearing on the crash beginning on 8 December in Baltimore, Maryland. Board chairman Jim Hall says the hearing "-will demonstrate the extraordinary effort being made to conduct an objective and far-reaching examination of all aspects of the flight 800 tragedy".

At the hearing, NTSB investigators will report on the progress of the probe, and technical witnesses will testify on safety issues that have arisen during the investigation. The hearing will be a fact-finding exercise and will not determine any cause of the crash.

Source: Flight International