Hawker 800 XP, Pilot Training Manual

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Revision 1 7-15
FOR TRAINING PURPOSES ONLY
HAWKER 800 XP PILOT TRAINING MANUAL
FlightSafety
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Fuel Flow Indicating
The fuel flow indicating system for each en-
gine consists of:
• Fuel Flow Transmitter
• Signal Conditioner
• Flow Rate Indicator
• Fuel Flow/Fuel Used Indicator.
The transmitter is a turbine-driven motor that
rotates and generates an AC electrical signal
as fuel flows past it. From the transmitter a sig-
nal conditioner converts the AC signal into
DC for the indicators.
A fuel flow indicator with an integral fuel used
indicator, on the center instrument panel dis-
plays fuel flow with a pointer moving over a
graduated scale. The unit displays fuel flow in
pounds-per-hour (PPH) from 0 to 2,200.
The fuel flow transmitter and indicators use
28 VDC power from the PS1 and PS2 bus-
bars. The left system receives power from the
PS1 busbar, and the right system receives
power from the PS2 busbar.
POWER CONTROL
INTRODUCTION
The power control system on the engine con-
sists of (see Figure 7-12):
• Throttle Levers
• High Pressure (HP) Fuel Cocks
• Fuel Control Unit
• Electronic Engine Computer
• Engine Synchronization.
Throttles
Each throttle lever on the center pedestal me-
chanically connects through cables and a tele-
flex control to a fuel control unit.
Movement of the throttle directly drives the
fuel control unit from idle to full power. In re-
sponse to throttle movements and engine pa-
rameters, the digital electronic engine coontrol
(DEEC) provides an electric signal to the hydro-
mechanical fuel control unit torque motor. The
fuel control unit either decreases or increases
the flow of fuel to the engine to provide over-
speed and overtemperature protection.
With the DEEC failed and OVSPD PROT se-
lected, or OFF selected, through the ENG
CMPTR switch on the overhead panel, the
throttle lever directly controls the engine
power through the fuel control governor.
The HP cock positions are in relationship to
the angle of rotation of the control shaft on the
FCU. The full aft (0°) position is the engine
fuel cutoff position. The idle (or engine start)
position is forward at 20°. To move the throt-
tle valve from idle to cutoff or from cutoff to
idle, the HP fuel cock lever must be lifted.
The throttle has unrestricted travel from idle
to full thrust, when the HP fuel cock lever is
in the forward position.
Audible Warnings and
Interlocks
The throttle levers operate two microswitches
through a cam on the throttle cable drum shaft.
Reducing power below 65 % N
1
rpm with the
landing gear not locked down below 150 kts
completes a circuit that sounds a warning horn.
Increasing power with the air brakes extended
while the landing gear is down will complete
a circuit that sounds a warning horn.
A mechanical locking device interconnects both
throttle levers to prevent simultaneous appli-
cation of engine power above 60 % N
1
with the
elevator gust lock installed. Although one throt-
tle at a time can be advanced to any setting.