Originally Posted by desirableroasted

The game reports "2 knots" at any speed between 2.0 and 2.99 knots (which is why you can move at "0 knots" -- you are at .9 knots, perhaps).

At 2.9 you are going to be making too many rpms to be silent. So, to be safe, check your rpms, not the reported speed.

That said, even at higher speeds you still may get away:

• you could be under a thermal layer. You won't know when you are, but they are modeled in GWX.
• the DD crew might not be very good.
• if you are deep enough, his hydrophone may overshoot you.

In 1939, you can, often and surprisingly, simply walk away from the scene of the crime at 3-5 knots and only 50 meters depth. By 1943, I am wishing for a crush depth of 500 meters and a pair of Dorothy's magic shoes.

But your mileage may vary.