Whauet>You also state that it they 'do not match the sound of a bomb' yet, I do not recall seeing the same comparison of the incidents based on the CVR sound of an actual 'bomb' that would show a definitive difference in the acoustic patterns from a confirmed bomb going off in the cargo hold. I am curious as to how the sound would differ if it were indeed a bomb that went off.
JBS>Good question and answered in the Air India Flight 182 AAR Kirpal report as explained by Mr. Ray Davis of the AAIB: A bomb sound has lower frequencies and a sharper rise time than the CVR sudden sounds. NTSB and AAIB and FBI have tried for years to match those sounds of Pan Am Flight 103 to a bomb but have failed. They have staged a real bombing in a real pressurized 747 with microphones all around. The reason the sound is not of a bomb explosion is because there was no bomb explosion. The sound has been matched from Air India Flight 182 to a DC 10 cargo door explosive decompression.
Whauut> Also, in reading several of the accident reports, it is stated in them that the main deck floor beams of UA811 buckled downwards (albeit slightly for that accident) as well as with the Turkish DC-10 accident, the floor showed definitive signs of buckling downwards. Yet the reports for the Air India and Pan Am indicate that not only did the floor beams, but the seat legs and even forensic evidence on the passengers in the immediate area all show an upward force having been exerted. I did not see that information in the TWA800 evidence, so I'm not including that in this question. I am curious as to how this discrepancy occurred if the initial event was the same for all accidents.
JBS>Yes, that is very important, floor beams buckled downward or pushed upward. Sucked down would be explosive decompression and pushed up would be bomb explosion. The evaluation was based on movement of the floor panels which indicated separation in an upwards manner. It may be that the sudden sucking down of the floor beams as they separated from the floor panels gave the impression that the floor panels went upward. Cup half full or half empty. For Air India Flight 182 the evaluations were done by viewing video of the floor beams as that area was not brought up.
For Trans World Airlines Flight 800 the data is absent although very crucial.
This floor beam movement is one area that needs to be reexamined from the point of view of ruling in or ruling out explosive decompression. Another area is the engine breakdown reports for Pan Am Flight 103. When the investigators looked for evidence of a bomb they found evidence of an explosion and assumed it was a bomb explosion, not an explosive decompression.
Whauet>Again, I am not an aircraft structure expert nor do I know physics aside from the basics, but if there was an initial explosion in the aircraft (whether it be a bomb or a fuel tank explosion), there would obviously be a great deal of overpressure created internally due to the expansion of gases. Those gases will try to escape the aircraft any means possible using the weakest point in the structure (and I use that term only in a frame of reference as it is an opening to the outside of the aircraft). That weakest point would be the cargo door in most cases -- blowing the door away from the aircraft as the floor buckles and full structural failure takes place. What would the difference in damage patterns be if the cargo door opening was the initial event, or if an explosion was the initial event creating the overpressure that may have caused the door to give way....
JBS>Allow me to digress...your post is typical of those that have an open mind. The questions are polite and pointed. I think you really want to know what happened. Your conjecture about the weakest point is that of an honest ‘bomb’ guy who might say, yes, the door ruptures, so what, the bomb did it. They never admit that because if the door ruptured open in flight then the question is why and United Airlines Flight 811 is best evidence.
I agree, if it were a bomb near the door, the door would rupture. So, more evidence of a bomb is needed. The NTSB did a thorough job of explaining why Trans World Airlines Flight 800 was not a bomb and all that required, but absent, evidence is the same evidence lacking in Pan Am Flight 103. There is actually more real evidence for a bomb explosion in Trans World Airlines Flight 800 than Pan Am Flight 103. My Smith AARs go into the bomb premise for all the accidents very deeply.
Now, how could one tell if a bomb blew the door open or it ruptured on its own. That point was raised by Bill Tucker of TSB when he visited me in December. I told him that would be for the structural engineers to determine. We guessed that a bomb explosion would be sudden and might not bend the torque tubes as the wiring/cargo door explanation supposes. Mainly, when a real bomb goes off in a real plane there is ample evidence of it. There is sooting etc. That inner door lining would have impacts, pitting etc to show the rupture was caused by the force of the internal explosion. All these doors have no evidence of a bomb explosion inside.
Another piece of evidence used by Judge Kirpal of India to find that a bomb caused Air India Flight 182 was something called ‘twinning’ in metal. It was said in 1986 that twinning was found and that was conclusive evidence of a bomb explosion. The Canadians demurred and it has since been proven that twinning can be caused by bomb, fuel tank explosion, and explosive decompression or whenever aluminum is subjected to intense pressure quickly.
There were explosions aboard all these aircraft. Each type of explosion leaves certain evidence. The scale weighs one way for a bomb, or missile, or fuel tank or open cargo door. For me, based on the forest of the five aircraft, the scale tips toward electrical/mechanical and away from conspiracy or fires with no ignition source, and that is because of United Airlines Flight 811 and its linchpin of the sudden sound followed by an abrupt power cut to the FDR.
The questions you ask would be answered with a reexamination of the actual wreckage of these planes from the point of view of ruling in or out the wiring/cargo door explanation. For the accidents at the time, the emphasis was on the prosecution building a case for bomb explosion which reflected the political tenor of the times.
Cheers,
Barry
Above is smooth port side forward of the wing, nose to left, of Trans World Airlines Flight 800 which contrasts to shattered starboard side forward of the wing. Wreckage distribution shows first parts to leave were just forward of the wing. A center tank explosion as the initial event would give bilateral damage, not the actual unilateral damage shown by the evidence.
It will be interesting to see the port side of China Airlines Flight 611 aft of the wing and compare with the starboard side. A repair doubler in the center failing would give bilateral damage, not unilateral.
Barry
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