What secondary mechanical event often precedes propellant release and subsequent ignition during a high-velocity water impact?

Answer

The transfer of immense shock energy shearing pipes or cracking welds.

The immense shock energy transferred through the airframe when momentum is abruptly stopped by water is more than enough to shear pipes or crack welds, which often precedes the propellant release.

What secondary mechanical event often precedes propellant release and subsequent ignition during a high-velocity water impact?

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