HEADQUARTERS OH-58A, Technical Manual

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TM 55-1520-228-10
(2) Ensure that gravity refueling port is
closed. If not, rotate inner sleeve counterclockwise until
gravity refueling port is closed and flange of sleeve is in
contact with rivet at base or receiving cylinder. Refer to
figure 2-23.
Ensure that servicing unit pressure is not above
125 PSI while refueling.
(3) Insert fueling nozzle into receiver and ac-
tuate automatic nozzle lever to ON or FLOW position.
Pin at base of nozzle will momentarily indicate when fuel
flow stops.
(4) Fuel flow will automatically shut off when
normal fuel level is reached. Just prior to normal shut off,
fuel flow may cycle several times as fuel level is reached.
Gage on servicing unit will indicate when flow is stopped.
(5) When fuel flow has stopped, actuate lever
on nozzle to OFF, disconnect nozzle from receiver and
replace filler cap.
(6) Disconnect fuel nozzle ground and rewind
hose assembly.
(7) Disconnect servicing unit ground at heli-
copter.
(8) Disconnect servicing unit ground at
grounding stake.
If helicopter is equipped with closed circuit
refueling system and fuel servicing unit is not
equipped with related nozzle for closed circuit
refuelling, a gravity system may be used pro-
viding the servicing nozzle does not exceed
1.75 inches outside diameter. To refuel utilizing
the gravity nozzle, it is necessary to position
the inner sleeve of receiver until slot is lined
up with fuel port in bottom of receiver. Position
nozzle into port in order to bypass closed cir-
cuit refueling system if caution is not used to
prevent damage to inner sleeve of receiver at
fuel port through improper use of nozzle.
d. Gravity Refueling.
(1) Ground the helicopter at the receptacle lo-
cated adjacent to the filler cap on the helicopter to the
filler-nozzle and remove filler cap.
(2) Rotate inner sleeve clockwise until sleeve
clears port in bottom of fuel receiver. Refer to figure
2-23.
(3) Position nozzle into port of fuel receiver.
(4) Fill to specified level.
(5) Remove nozzle and rotate inner sleeve
counterclockwise until gravity refueling port is closed
and flange of inner sleeve is in contact with rivet at base
of receiver cylinder.
(6) Reinstall filler cap.
(7) Disconnect fuel nozzle ground and rewind
hose.
(8) Disconnect servicing unit ground at heli-
copter.
(9) Disconnect servicing unit ground at
grounding stake.
2-78. FUEL SYSTEM SERVICING. (RAPID (HOT)
REFUELING).
WARNING
When it is determined that rapid (hot) refuel-
ing is required (prescribed in FM 10–68), proper
grounding of aircraft must be accomplished.
a. Precautions.
NOTE
Servicing personnel shall comply with all safety
precautions and procedures in FM 10–68.
NOTE
If the nozzles do not reduce the fuel pressure to
less than 25.5 PSIG, the receiver is designed to
shut off fuel flow.
(1) Ground the helicopter at the receptacle lo-
cated adjacent to the filler cap on the helicopter to the
filler-nozzle before removing filler cap.
2-60 Change 12