Hawker 800 XP, Pilot Training Manual

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Revision 1 7-5A
FOR TRAINING PURPOSES ONLY
HAWKER 800 XP PILOT TRAINING MANUAL
FlightSafety
international
Accessory Drive
An accessory drive gearbox and transfer gear-
box are driven from the high pressure (N
2
)
spool. The transfer gearbox is driven by a ver-
tical shaft and in turn drives the accessory
gearbox through a horizontal gearshaft. The
accessory drive gearbox provides shaft power
for aircraft accessories (hydraulic pump,
starter/generator and alternator) which are
mounted on the forward face of the accessory
gearbox. The fuel pump, fuel control unit and
oil pump are all mounted on the rear face of
the accessory gearbox.
OPERATION
When the engine is operating (Figure 7-4),
the single-stage fan draws air in through the
nacelle inlet duct. The outer diameter of the
fan accelerates a moderately large air mass at
a low velocity into the full-length bypass duct.
At the same time, the inner diameter of the fan
accelerates an air mass into the engine core.
The pressure of this air is increased by the LP
compressor and directed to the HP compres-
sor where the air pressure is further increased
and ducted aft to the combustor.
A precise amount of this air enters the re-
verse-flow combustor where fuel is injected
by the twelve spray nozzles. The mixture is ini-
tially ignited by the two igniter plugs and ex-
panded through the turbine. The HP turbine
extracts enough energy to drive the HP com-
pressor and the transfer and accessory gears.
The LP turbine extracts enough energy to drive
the LP compressor, the planetary gear, and
the fan.
Figure 7-4. Gas Flow