TM 55-1520-240-23-10
16-1
EXTERNAL CARGO HOOK SYSTEM
16-1
DESCRIPTION
The external cargo hook system consists of three
separate cargo hooks mounted on the underside of the
helicopter. The system allows a single load to be carried
suspended at up to three points or three separate loads
to be carried at the same time.
NO BREAK - WORK HARDER
The center cargo hook is suspended from a beam under
the cabin floor at sta. 331. The hook is attached to the
beam with a bolt that lets the hook swing to each side.
The beam is carried in bearings attached to structure at
the sides of the rescue hatch in the floor. It can pivot
forward and aft from the attaching points.
NO BREAK - WORK HARDER
When not in use, the hook is stowed between cabin floor
and rescue hatch door. In use, the hatch door is opened
and the hook is unstrapped to hang down through the
open hatch. The hook lifting capacity is 26,000 pounds.
NO BREAK - WORK HARDER
The forward and aft hooks hang from fittings attached
to the floor beams at sta. 249 and 409. Each fitting is
a universal type that allows the hook to swing forward
and aft and from side to side. Normally the hook is
electrically actuated through a connector on the fuselage
skin. It can also be released manually through a cable
that connects to a release mechanism. The lifting
capacity of each hook is 17,000 pounds. When used
together, the two hooks can lift a load of 25,000 pounds.
NO BREAK - WORK HARDER
All three hooks can be released in any one of three
modes: normal, emergency, or manual. See Task 16-2
for a description of hook operation in each of these
modes.
NO BREAK - WORK HARDER
Power to operate the cargo hook system in normal
operation comes from the No. 2 28 vdc bus. Two circuits
are provided, each controlled by a separate circuit
breaker. One circuit provides power to the system. The
other contains the control switches and relays. Two
separate power and control circuits are provided for
emergency release of the hooks. Again, each has its
own circuit breaker.
16-2
