HOOK OPEN caution capsules come on
and the hooks open or the solenoids acti-
14. CARGO HOOK MSTR switch RESET
and release to OFF. Check all HOOK OPEN
cautions go out and the hooks close.
15. To confirm safety of the cargo hook system,
the pilot, copilot, and flight engineer each
press a CARGO HOOK RELEASE switch to
attempt to open cargo hooks with the CAR-
GO HOOK MSTR switch at OFF.
4-3-17. Normal Operation of Cargo hooks.
Normal operation of the cargo hooks from the cockpit or
from the cargo compartments is as follows:
1. CARGO HOOK MSTR switch ARM. (If
used from the cockpit or the cargo compart-
2. HOIST OPERATORS PANEL CARGO
HOOK switch ARM. (if used from the
3. HOOK SEL switch ROTATE to hook or
hooks to be released.
4. CARGO HOOK RELEASE switch Press.
(From either the cockpit or the cargo
5. Master caution panel Check HOOK
OPEN cautions come on.
6. Loads Check released. If the forward or
aft hooks did not open because of sling
slack, press the release switch and lift the
helicopters to apply a strain to the sling and
pull the hooks open.
4-3-18. Emergency Operation of Cargo Hooks.
Refer to Chapter 9 for emergency operation of cargo
4-3-19. Helicopter Internal Cargo Handling System
An internal cargo handling system is provided for quick
loading securing and unloading of palletized cargo (fig.
4-3-15 and 4-3-17). The system consists of a set of rail
assemblies and guide roller assemblies that are secured
to the helicopter floor. For descriptive information, ser-
vice/maintenance instructions. operation, installation
and removal instructions, refer to TM 55-1680-358-12 &
The system has three main sections: a cabin section, a
ramp section, and a ramp extension section (fig. 4-3-17).
The cabin section has outboard rail/rollers along both
sides of the cabin, and inboard guide rollers running
along the center of the cabin. There are six outboard
rail/roller assemblies, three on each side of the cabin.
Each of the six rail/roller assemblies has its own dedi-
cated location in the helicopter. The left and right side rail/
roller assemblies are symmetrically opposite. There are four
inboard guide roller assemblies mounted in the center of the
cabin floor. All of the outboard and inboard guide roller as-
semblies are installed by being bolted to the existing tiedown
fitting locations in the cabin floor.
The system is equipped with a set of locking devices and
tiedown fittings for securing loaded cargo.
All cargo must be properly restrained to en-
sure safe operation of the helicopter and the
safety of personnel. Loads must be restrained
in accordance with procedures and guide-
lines in Chapter 6 and TM 10-450-2, Helicop-
ter Internal Loads.
The ramp section has two inboard roller assemblies along
the center of the ramp and two outboard guide/roller assem-
blies along the sides of the ramp. A ramp support assembly
is used to support the ramp when loading or unloading the
helicopter with the ramp in the horizontal position
The ramp extension section has two ramp extension roll-
er assemblies and two ramp extension support assem-
blies to support the ramp extensions when loading and
unloading with the ramp in the horizontal position.