When a sudden unexpected mechanical event occurs, certain mechanical events follow. There have been four confirmed instances where pylon fuse pins fail and the aircraft is there to be available for inspection. Certain sequences occurred when those fuse pins failed. They occur during a stress event such as severe turbulence or hard landing. The engine detaches, goes forward, flips up and back, taking wing leading edge material with it affecting flap action but not affecting adjacent engine.
Pilot immediately reports engine lost when engine falls away.
There is no delay between report of trouble and report of engine lost. Things fall from the aircraft. There have been two unconfirmed but official explanations of fuse pin failure for two Boeing 747 crashes. The mechanical sequence which occurs after the initial sudden unexpected mechanical event does not follow the confirmed sequence, but does follow the confirmed mechanical sequence when a forward cargo door opens in flight. The two confirmed instances where the forward cargo door failed and the aircraft is available for inspection a certain sequence was followed.