TM  1-1520-240-10 2-4-4            pounds per hour in 100 pound increments. The signal to drive the indicator is derived from a fuel Figure  2-4-5.  Fuel Flow Indicator. flow transmitter in the fuel line of each engine at the quick disconnect shelf. Power to operate the No. 1 indicator is from the No. 1 AC bus through the ENGINE NO. 1 FUEL FLOW circuit breaker on the No. 1 DP. Power to operate the  No.  2  indicator  is  from  the  No.  2  AC  bus  through ENGINE NO. 2 FUEL FLOW circuit breaker on the No. 2 PDP. 2-4-10.  Pressure Refueling System. The pressure refueling system permits rapid refueling of all fuel tanks simultaneously or selective refueling of any tank or combination of tanks. Maximum fueling rate is 300  gallons  per  minute  at  55  psi.  The  system  control panel and refueling nozzle receptacle are on the right side  of  the  helicopter  above  the  forward  right  landing gear (fig. 2-4-6). In addition to the control panel and refueling receptacle, the system consists of dual fuel level control valve, a dual fuel shutoff valve in each tank, a jet pump in each main tank, and pressure refueling manifold. a. Dual  Fuel  Level  Control  Valves  and  Dual  Fuel Shutoff Valves.  The dual fuel level control valves control the operation of the fuel fuel shutoff valves. When fuel in a tank rises to the full level during pressure refueling, the floats in the control valve close and apply a signal to the shutoff  valve,  closing  it.  the  floats  can  also  be  closed electrically to stop fuel flow into a tank at some intermedi- ate level. The floats are controlled by the FUEL CELL SHUTOFF VALVE TEST switches on the refueling con- trol panel. b. Jet Pumps.  The jet pump installed in each main tank  evacuates  the  refueling  manifold  and discharges the displaced fuel into the main tank. The jet pump is activated when the forward boost pump in each main rank is first turned ON following pressure refueling. c. Pressure Refueling Manifold.  The pressure re- fueling  manifold  connects  to  all  tanks  to  the  pressure refueling receptacle. It does not include projectile resist- ant features because the fuel is evacuated before flight by the jet pumps. Electrical power is applied to the system only when the REFUEL STA switch on the cockpit FUEL CONTR panel is placed to ON. Power to operate the pressure refueling system  is  supplied  by  the  DC  switched  battery  bus through the REFUEL circuit breaker on the No. 1 PDP. 2-4-11.  Controls and Indicators. Except for the REFUEL STA switch on the cockpit FUEL CONTR  panel,  all  pressure  refueling  system  controls and indicators are on the pressure refueling station panel (fig. 2-4-6). 2-4-12.  PWR Control Switch. The PWR (power) control switch is labeled ON and OFF. When placed to ON, electrical power is applied to the pressure refueling system and to the refueling station quantity indicator provided the REFUEL STA switch on the cockpit FUEL CONTR panel is at ON. Also, the PWR ON  light  will  illuminate,  the  fuel  quantity  indicator  will register the quantity of fuel in the tanks, and the REFUEL VALVE POSN lights will illuminate momentarily. When placed to OFF, electrical power is removed. 2-4-13.  REFUEL STA Switch. The REFUEL STA switch is on the cockpit FUEL CONTR panel (fig. 2-4-1) when placed to ON, applies electrical power from the DC switched battery bus to the PWR ON switch on the refueling station panel. Setting the switch to OFF after pressure refueling, closes the refuel valves and discontinues electrical power to the refueling panel. When pressure refueling, be sure the switch is at ON at all times. If the switch is at OFF, the aft auxiliary tanks will not fill, the remaining four tanks will fill to maximum, the refuel station quantity indicator is inoperative, and there is no precheck capability. 2-4-14.  Fuel     Quantity     Indicator     and     Selector Switch. The pressure refueling station fuel quantity indicator and selector switch (fig. 2-4-4) are identical to those in the cockpit. The indicator at the refueling station indicates fuel quantity only when the REFUEL STA switch on the cockpit FUEL CONTR panel (fig. 2-4-1) is at ON and the PWR switch on the refueling station panel (fig. 2-4-6) is at PWR ON. Electrical power to drive the indicator is AC from a solid-state inverter in the cabin at sta 220. The inverter, in turn, is powered by the DC switched battery bus through the FUEL REFUEL circuit breaker on the No. 1 PDP. 2-4-15.  FUEL CELL SHUTOFF VALVE TEST Switches. Seven  three-position  FUEL  CELL  SHUTOFF  VALVE TEST switches are on the refueling control panel (fig.