Let's say that due to fancy driving and a throttle linkage failing at
the wrong time somebody drove their ten tonne hardboat into a pair of
your parked RIBs such that witnesses said both went into the air. And
that as well as bent steering wheel and diving bottle rack there was a
worrying crack in the fiberglass.

Knowing a lot more than me what kind of testing would you expect to be
done ?

Isn't there more to checking the structural integrity of a boat than
just random hammer testing ?

Jon