Hawker 800 XP, Pilot Training Manual

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6-10
FOR TRAINING PURPOSES ONLY
HAWKER 800 XP PILOT TRAINING MANUAL
FlightSafety
international
Reduction Drive Assembly
The reduction drive assembly is a small plan-
etary gear assembly driven by the turbine shaft.
The planetary system reduces the high turbine
rpm to the values required for the various ac-
cessories which consist of the following:
• Oil pump
• Fuel pump and fuel controller
• DC starter-generator
• Tach generator
OIL SYSTEM
General
The APU oil system is a self-contained, fully
automatic system which provides for cooling and
lubrication of the rotor bearings and the bear-
ings and gears in the reduction drive assembly.
FUEL SYSTEM
General
The APU fuel system is a fully automatic sys-
tem with no operator controls or adjustments,
The fuel system functions to control the APU
during starting and acceleration, and provides
for a nearly constant rpm under all operating
conditions.
IGNITION SYSTEM
General
The APU ignition system is a high-energy ca-
pacitor discharge system. The ignition exciter
is mounted on the APU and supplied with DC
power from the distribution system. A high-
tension lead connects the exciter to a single ig-
n i t e r p l u g i n t h e c o m bu s t o r. I g n i t i o n i s
operational from the initiation of the startup
to 90% rpm when it is terminated by a speed-
sensing switch.
Electronic Sequence Unit (ESU)
The ESU controls startup and monitors the APU
while it is operating. Any malfunction of the
APU will result in the ESU shutting it down.
CONTROL AND INDICATIONS
General
Control, indication, and warning for the APU
(Figure 6-5) are all provided on a single panel
located on the side face of the bulkhead behind
the pilot’s seat. The panel contains the fol-
lowing controls and indicators.
APU MASTER Switch
The APU MASTER switch is a two-position,
ON–OFF switch. When the switch is on, elec-
trical power is available to the APU control
panel.
TURBINE START Switch
The TURBINE START switch is a momen-
tary, pushbutton switch. When pushed, the
switch will initiate the automatic start se-
quence of the APU.
BLEED AIR Switch
The BLEED AIR switch is a two-position,
ON–OFF toggle switch. The function of the
BLEED AIR switch is to control the elec-
tropneumatic bleed valve that supplied APU
bleed air to the airplane’s environmental sys-
tem when the airplane is on the ground. For
m o r e i n f o r m a t i o n o n A P U b l e e d a i r, s e e
Chapter 9, “Pneumatics” and Chapter 11, “Air
Conditioning.”
NOTE
Wi t h t h e Tu r b o m a c h A P U , A P U
bleed air is available in flight.