Quite immersive, especially in the sound design.
I really like what you did there with the submarine controls directly on the screen as if you had the actual instruments pannel in front of you
That being said i feel the game doesn't really have issues itself but more that it falls in the category of " not for everybody" in the sense that it has quite a complex simulation aspect to it and is awesome for that, but might be a bit complex to grasp if you're not into this type of game. So not really an issue but more something to take into account i think.
But to sum up, solid entry, very nice art and sound design, and impressive that you made such complex mechanics for a jam game.
Good job :)