PPRuNe Forums - Attention B737 Drivers

INFORMATION ON THAI AIRWAYS INTERNATIONAL
BOEING 737 EXPLOSION
April 11, 2001

The National Transportation Safety Board is providing technical
support to the Government of Thailand's investigation of a March 3, 2001
explosion and fire that destroyed a 9-year-old Thai Airways International
Boeing 737-400 (HS-TDC) that was sitting at a gate at Don Muang
International Airport, Bangkok, Thailand. A flight attendant aboard the
plane was killed in the blast and subsequent fire, which destroyed the
airplane.

The Government of Thailand, in conjunction with the NTSB, is
releasing the following information:

On March 22, 2001, Deputy Prime Minister Chavalit Yongchaiyudh related that
the investigation is actively pursuing all potential causes for the loss of
the airplane and that nothing has been ruled out at this time.

Physical evidence has been found that the center wing tank exploded. The
accident occurred at 2:48 p.m. on a day with temperatures in the high 90s
Fahrenheit. The initial explosion of the center wing tank was followed 18
minutes later by an explosion in the right wing tank. Air conditioning
packs, which are located directly beneath the center wing tank and generate
heat when they are running, had been running continuously since the
airplane's previous flight, including about 40 minutes on the ground.

Although chemical traces of high energy explosives were initially believed
to be present, samples have been submitted to the FBI for confirmation by
laboratory equipment that is more sensitive than equipment available in
Thailand. Although a final report has not yet been issued, the FBI has
found no evidence of high explosives in any of the samples tested to date.

Despite a thorough examination of the wreckage by Thai and American bomb
experts, no physical evidence of a bomb has been found to date.

The NTSB has a library of sound signatures recorded from previous flights
and tests, including both fuel air explosions and high explosive charges.
The recording of the HS-TDC explosion has features that are similar to
recorded features of a Philippine Airlines 737-300 center wing fuel tank
explosion in May 1990. Neither recording includes a precipitating sound of
an initiating explosion that may have ignited the fuel tank.

Many parts from HS-TDC, including fuel pumps and wiring, have been removed
and are to be analyzed in laboratories.

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NTSB Press Contact: Ted Lopatkiewicz
(202) 314-6100

Several photos from the accident scene are linked to this release on
the Board's web site, www.ntsb.gov <http://www.ntsb.gov>, under "News &
Events," "Press Releases."