There's a little bug for speedboats.
If you exit it when it's not fully stopped, it will keep to move forward at the same speed it was.
If you come to a complete stop, instead, is going to stay exactly where it is when you exit it

It'll keep moving no matter what. Exited when it was zero mph, and resurfaced a couple minutes later and found it moved about a mile out!

Strange.. i played a diving mission with a friend, insertion via speedboat, swim 1.5 Km to the target, do the obj and then get back and the boat was still there and it was with bad weather (high waves)

+1

The water element begins to be pretty realistic already IMO, but this is one of the must-features that are lacking atm

The anchor should be visible underwater too!

OK. Tried it again last night, and the boat was still there too after making sure I set movement to 0 MPH and Engine Off. Maybe the movement was still +0.5 or +1 MPH, or maybe it was an exit quirking the MPH up. Still needs an anchor?

I also found, instead of trying to depend on reverse to throttle to a full stop, simply do a few full U-turns or quick circles, preferably away from the target and shoreline to prevent sticking or getting shot.

Like I said, I'm far from being a Navy guy. ;-)

Bug #3992 "Difficult to Stop Boats" might be relevant to this bug.

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