Figure 2-18. Fuel Management Panel

TM 1-1510-223-10 2-36 1. Standby Pump Switch (#1 Engine) 5. Standby Pump Switch (#2 Engine) 2. Fuel Quantity Indicator (#1 Engine) 6. Auxiliary Transfer Override Switch 3. Fuel Quantity Main/Auxiliary Gaging System Selector Switch 7. (#2 Engine) Crossfeed Switch 4. Fuel Quantity Indicator (#2 Engine) 8. Auxiliary Transfer Override Switch (#1 Engine) Figure 2-18. Fuel Management Panel primary high-pressure pump for engine starting and all normal operations. Either the engine-driven boost pump or electric standby pump is capable of supplying suffi- cient pressure to the engine-driven primary high-pres- sure pump and thus maintaining normal engine operation. b. Standby Fuel Pumps. A submerged, electrically- operated standby fuel pump, located within each nacelle tank, serves as a backup unit for the engine-driven boost pump. The standby pumps are switched off during nor- mal system operations. A standby fuel pump will be oper- ated during crossfeed operation to pump fuel from one nacelle tank to the opposite engine. The correct pump is automatically selected when the CROSSFEED switch is activated. Each standby fuel pump has an inertia switch included in the power supply circuit. When subjected to a 5 to 6 g shock loading, as in a crash situation, the inertia switch will remove electrical power from the standby fuel pumps. The standby fuel pumps are protected by two 10-ampere circuit breakers placarded STANDBY PUMP #1 or #2, located on the overhead circuit breaker panel (fig. 2-7), and four 5-ampere circuit breakers (two each in parallel) on the hot battery bus. c. Fuel Transfer Pumps. The auxiliary tank fuel transfer system automatically transfers the fuel from the auxiliary tank to the nacelle tank without pilot action. Motive flow to a jet pump mounted in the auxiliary tank sump is obtained from the engine fuel plumbing system downstream from the engine driven boost pump and routed through the transfer control motive flow valve. The motive flow valve is energized to the open position by the control system to transfer auxiliary fuel to the na- celle tank to be consumed by the engine during the initial portion of the flight. When an engine is started, pressure at the engine driven boost pump closes a pressure switch, which after a 30 to 50 second time delay to avoid depletion of fuel pressure during starting, energizes the motive flow valve. When auxiliary fuel is depleted, a low level float switch de-energizes the motive flow valve after a 30 to 60 second time delay. This time delay function prevents cycling of the motive flow valve due to sloshing fuel. If the motive flow valve or the associated control cir- cuitry fails, the loss of motive flow pressure when there is still fuel remaining in the auxiliary fuel tank, is sensed by a pressure switch which illuminates a caution annun- ciator placarded #1 NO FUEL XFR or #2 NO FUEL XFR. During engine start, the pilot should note that the NO FUEL XFR annunciator extinguishes 30 to 50 seconds after engine start. The NO FUEL XFR annunciator will not illuminate if auxiliary tanks are empty. A manual override is incorporated as a backup for the automatic transfer system. This is initiated by placing the AUX XFER switch, located in the fuel management panel to the OVRD position. This will energize the pedal, forward