TM 55-1680-320-23 & P
1-8. Equipment Data.
Weight (wet) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...180.0 lbs. (81.72 kg)
Height (min) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..50.90 in. (129.28 cm)
(max) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..5l.9l in. (131.85 cm)
Length (min) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..33.58 in. (85.29 cm)
(max) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35.38 in. (89.86 cm)
Width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13.50 in. (34.29 cm)
Power Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..125 amps max. @ 28 vdc
Rated Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .600 lbs. (272.40 kg)
Limit Load. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1800 lbs. (817.20 kg)
Lubricating Oil (normal use) . . . . . . . . . . . . . . . . . . . . . NSN 9150-00-698-2382
(below .40ºF (-400C)) . . . . . . . . . . . . . . . . . . . . . . . . . ..MIL-H.5606
1-9. Safety, Care, and Handling. Observe all general precautions and safety regulations when handling the rescue
hoist.
Section III TECHNICAL PRINCIPLES OF OPERATION
1-10. Rescue Hoist Assembly. The Rescue hoist assembly (Figure 1-2) is intended for installation on all UH1 Series
helicopters. The hoist is an electronically powered unit consisting of five major assemblies; winch assembly, boom
head assembly, boom position support assembly, control panel assembly, and control pendant assembly. The hoist
has a 260 foot (792.5 dm) cable and 600 pound (272.4 kg) rated load. Lift speed at rated load is 125 feet (381 dm)
per minute (250 feet (762 dm) per minute at 300 pound (136.2 kg) load).
The hoist uses aircraft power, and can
be operated by one man.
1-11. Winch Assembly.
a. The winch assembly (Figure 1-3) consists of a winch mechanism, limit switch drive assembly, electric motor, brake
cooling pump, automatic clutch and brake assembly, inertia dump assembly, and the cable hook.
b. The limit switch drive assembly contains four positive action limit switches that control extension and retraction
rates of the rescue cable. One limit switch prevents extension (unreeling) of the cable beyond established limits. A second
switch operates when the cable reaches 3 to 5 safety wraps frorn full reel off (down limits at 250 (762 dm) foot maximum
extension). A third switch operates the rewind (reeling) caution indicator, decelerating the hoist to 50% speed when the
cable hook is with 10 feet (30.48 dm) of full stowed position. The fourth limit switch operates the hoist when the cable
hook reaches 18 inches from full stow (decelerating to 12 feet (36.58 dm) per minute).
c. The automatic brake and clutch assemblies actuate to prevent reeling or extension of the cable when maximum
load is exceeded Two thermal temperature sensing switches monitor winch and brake operation, actuating when system
components exceed safe temperature limits. The brake cooling pump acts to regulate brake and clutch operating temperatures.
1-7
