TM 55-1520-240-23-8
10-1
FUEL SYSTEM
(Continued)
10-1
REFUELING
There are two methods of refueling the helicopter.
Gravity Fill Refueling —
Each tank has a gravity fill port which is opened
for individual tank refueling. About 30 minutes are
necessary to refuel the helicopter by this method.
Single Point Pressure Refueling —
The pressure refueling system allows the aircraft to
be completely refueled in about 4 minutes with fuel
supplied at 300 gallons per minute at 55 psi. Refueling
is controlled by a panel located in the right front intertank
area. Fuel enters the pressure refueling adapter and
goes to the forward auxiliary tanks through a breakaway
fitting on the aft access door. Fuel enters the main tanks
through the bottom orifice of a split manifold. The top
orifice of the manifold is connected to a tube which runs
through the main tank and supplies the aft auxiliary
tank. Two sensing tubes between the high level control
valve and shutoff valve cause the shutoff valves to close
when each tank is filled. The jet pump draws fuel from
the forward pressure refueling lines when the main tank
boost pumps are turned on. On aircraft with 68 a
vacuum relief check valve opens when fuel is drawn
from the pressure refueling lines. Air is drawn into the
pressure refueling lines as the jet pump removes the
remaining fuel, and prevents a vacuum from forming
in the lines. On aircraft with 82 installed, the internal
tanks can also be refueled using this method.
NO BREAK - WORK HARDER
The capacity of the airframe fuel system is 1034 gallons
when all tanks are filled.
NO BREAK - WORK HARDER
The capacities of individual tanks are shown below:
10-11
