Question

On October 4" 1992, an El Al 747 freighter crashed in Amsterdam, killing all four people on board and over 50 people on the ground. The cause of the crash was the number 3 and 4 engines separated from the wing, causing a loss of control. From a corrosion engineer's standpoint, discuss the main failure contributed to the corrosion and prevention action should be considered

Please provide cause of corrosion and details.

Answer 1

Introduction Initial investigation revealed that crash was due to disintegration of the get engine for understanding whether the pin failure was a consequences or the cause of the crash. fractography Investigato need to be done.

Fractography test result Macroscopic study of fraufuge reveals that face little deformation had fast plore and fracture was very flat ne, Fracture created by overload during crash. Charactastic of traus crystalline stress Cormsston pits, tunnels and slots were found near both the pin inner and outes penone for sec test (stress Corrosion cracking a test) resut The required stress for see was Residual stress arising from the prodretion method. Go is Nitmnie prone to see The Infanal annulus space was at seased from environment e t possible that the commune engronment. penetrated into the se internal spares Eodeunce that this really decused during service will be given later, I thence

Conclusion The main enise e of the crash was that enque, manufactures selectate an sce drone maferial intronic 6o for pins of levers of compressor variable vanes in the design stage. The solution has been to change pin mafariah. The first levels with the new pins ma ferias were delivered less than five months after the the accident. The frequent inspections an the levers with the old som were Continued untill all these lever had been replaced.
According to stress corrosion cracking test and fractography test done on the crash the following conclusion is obtained.