You control the patrol boat in this game.
The boat can be moved left and right and can release depth charges.
You may use joystick 
or keyboard to control the patrol boat. See Setup
Increases the speed to the left, or brakes if the boat is moving to the right.
Increases the speed to the right, or brakes if the boat is moving to the left.
Each time you press a movement key the speed is affected one step.
Maximum speed is achieved by pressing a key three consecutive times, (from standing still).
If you repeatedly press the left key when the boat is moving right, then the speed is first decreased to zero before it starts to move left. (Same the other way round)
You can hold down the key to quickly change direction of the boat. Acceleration tip
You can release/throw depth charges from both the stern and the bow of the ship.
Left side, at the stern of the ship.
Right side, at the bow of the ship.
The number of available depth charges is shown by the bomb counter, 
, located near the top of the screen. The bomb counter is reduced every time you drop a depth charge and increased when a depth charge explodes. The number of depth charges varies from level to level. In general there will be more charges for you to drop as the levels becomes harder. The chosen play skill mode also affects the number of depth charges. See Play skill modes�
Use the throw key to throw the depth charges longer away from the ship.