Crush Depth

Bay of Biscay, October 1943. After nine hours of depth charges the commander surfaced into the destroyers' searchlights and ordered the boat abandoned and scuttled. Paul Ahrens, nineteen, was lying stunned behind a jammed door in the motor room. He comes to as she lies awash, hears laughter across the water – and then the sea closes over the boat with him inside.

Crush Depth is a first-person survival horror game and systems simulator. There are no monsters. There is a 40 m steel tube on a mud ledge, the hiss of the sea forcing its way in under sixteen bar, the hull groaning as it takes the weight, a dead friend under a blanket, and a gramophone on the shelf. Draw up the stern gland, shut the sea-cocks, drive wooden plugs into the leaks, keep the water away from the batteries before they gas you, pump, trim, close the vents and blow the tanks in the right order – with a finite amount of compressed air and no second chance.

Every number is simulated: leak flow from the real pressure difference, water levels that stay level while the boat tilts, compressed air pockets, Boyle's law in the ballast tanks, chlorine gas, cold, nitrogen narcosis and the bends. Waste air, let her get too heavy or too steep, and she will slide off the ledge into a thousand metres of water.

Needs a desktop browser with WebGL 2, a keyboard and a mouse. Headphones recommended. Contains disturbing themes (war, death, drowning).

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