The LRU-12/A life raft assembly (fig. 5-21)
consists of a four-man inflatable life raft and an
inflation assembly (a CO2 cylinder with an infla-
tion valve and a manifold). The life raft has an
orange flotation tube that is divided into two
separate compartments by two internal vertical
bulkheads. These two compartments are called the
bow and the stern. The raft has a noninflatable
floor with an inflatable seat in the bow section.
This seat is manually inflated through the topping-
off valve using the hand pump. A lifeline encircles
the flotation tube. A righting line and accessory-
container securing line are attached to the lifeline.
Survival equipment is stowed in the accessory
container and a supply pocket attached to the
flotation tube. A sea anchor is attached to the
bow, a boarding stirrup is attached to the stern,
and heaving lines equipped with rubber weights
are attached at each end. Two topping-off valves
and four boarding handles are located on the tube.
Three righting handles are located on the under-
side of the life raft floor. Two boarding handles
are located on the topside of the floor, one
amidships in the center, the other athwartships
towards the stern. The life raft CO2 inflation
assembly and accessory container are contained
in the LRU-12/A carrying case. When the life raft
is fully inflated, it measures 9 1/4 feet long.
Inflation Procedures. Like other flotation
equipment, the LRU-12/A has a CO2 type of
inflation system. This system can be installed to
operate automatically or manually, depending
upon aircraft installation.
The LRU-12/A is also equipped with a hand
pump for manually inflating the two-section
flotation tube and/or the inflatable seat and is
stowed in the accessory container. The pump-
attaching fitting and the topping-off valve are
designed to allow a positive connection. To use
the hand pump, follow the steps listed below:
NOTE: In the absence of a CO2 t y p e o f
inflation system, manual inflation starts with the
seat section. It fills quickly and provides flota-
tion for the raft while the main flotation tubes
are being inflated.
l Screw the inflation end of the assembly
hose of the hand pump into the topping-off valve
Figure 5-23.Survivor holding the hand pump while attaching the assembly hose to the topping-off valve.