This chapter contains information about the two HRUs used on US watercraft. Can Type hydrostatic release device and the Hammer H20 hydrostatic release device.
Components are replaceable off the shelf.
The thin walled aluminum can is designed to be crushed by the pressure of water at a depth of 25 feet plus or minus 15 feet. The wall thickness of the can is such that it can be damaged during installation or inspection. The thin walled aluminum can forms a water tight seal that is the heart of the hydrostatic release. Collapsing of the aluminum can will allow the end brackets to release the life raft from its stowage. It is designed to collapse by water pressure.