"Roger Long" wrote in news:46add541$0$16582
:

The jet boat could
probably plow right through an oyster bar and keep right on operating
although the transducers and bottom paint would suffer.


That really depends a LOT on which jet pump is used. If the jet used has a
stator a few cm behind its spinning impeller, it will very soon be
destroyed by the first piece of hard flotsam that it ingests. Case in
point is any jetski jet or the Mercury SportJet pumps. The spinning
impeller is very, very close to the cast aluminum stator used to stop the
water spinning out the back and is required to produce linear thrust. If
ANYTHING gets between that stator and the prop, it eats the drivetrain,
instantly.

Not all jets are made for river bottom dragging service like those
wonderful jetboats made in Oz.....(c; You get a SportJet near the bottom,
it's going to be a very expensive cruise...very quickly.

Larry
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