In the company's investigation, it was noted that during a stop in Turkey, ground crews had filed the cargo door's locking pins down to less than a quarter of an inch (6.4 millimetres), when they experienced difficulty closing the door. Subsequent investigative tests proved the door yielded to approximately 15 psi (100 kPa) of pressure, in contrast to the 300 psi (2,100 kPa) that it had been designed to withstand.
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Now, I thought I knew everything publically available surrounding Ship 29, having read the report in depth, all of the books available and various websites over many years - however I never knew this and am quite astounded (referenced from Wikipedia).
From the referenced Chicago tribune article:
Shortly after Alan Tetelman* of Failure Analysis arrived in Paris to inspect the wreckage, he noted that the pins on the cargo door had been filed down deliberately. By asking a few questions, he then learned that on a stop in Turkey, the ground crews had trouble closing the door, which then closed effortlessly by taking less than a quarter inch off the pins. By doing so, it was proved through tests, the door yielded to about 15 pounds of pressure, while it had been designed to withstand 300 pounds.
This puts a different slant on some aspects of this crash. Again I am astounded by this as it is entirely new to me.
Any thoughts?
* Professor of Engineering and Applied Science UCLA - Who then lost his life in 1978 in the PSA 727 mid-air... an amazing coincidence.