787 Flight Crew Operations Manual
DO NOT USE FOR FLIGHT
Engines, APU -
Engine System Description
Copyright © The Boeing Company. See title page for details.
7.20.16 D615Z003-TBC
[Option – RR engines]
Fuel is supplied by pumps located in the fuel tanks. The fuel flows through a spar
valve located in the main tank. It then passes through the first stage engine fuel
pump where additional pressure is added. It flows through a fuel/oil heat
exchanger where it is preheated. A fuel filter removes contaminants. The second
stage of the engine fuel pump adds more pressure before the fuel reaches the fuel
metering unit. The fuel metering unit adjusts fuel flow to meet thrust
requirements. Leaving the FMU, the fuel flows through a high pressure filter and
then through the engine fuel valve into the engine.
The spar and engine fuel valves allow fuel flow to the engine when both valves
are open. The spar valve opens when the engine fire switch is IN and either the
START selector is in START or the FUEL CONTROL switch is in RUN. The
engine fuel valve opens when the engine fire switch is IN and the FUEL
CONTROL switch is in RUN. Both valves close when the engine fire switch is
OUT, or the FUEL CONTROL switch is in CUTOFF and the START selector is
in NORM.
Fuel flow is measured after passing through the engine fuel valve. Fuel flow is
displayed on the secondary engine display. Fuel flow information is also provided
to the FMS.
February 15, 2010
To Next Page
Loading...
