When the ship sinks, the hydrostatic release unit actuates
at a depth of 2 to 4 m and disconnects the lashing wire and painter
from the cradle, and the container floats to the surface of the water.
At this time, the operating line fastened to the cradle is pulled
and inflation of liferaft is started. The raft is released from the
sinking ship and floats to the surface. With this mechanism, the painter
and operating line are separate, so there is no need to provide a
weak link.