Revision 1
7-17
FOR TRAINING PURPOSES ONLY
HAWKER 800 XP
PILOT TRAINING MANUAL
FlightSafety
international
HP Fuel Cocks
Each high pressure (HP) fuel cock control
lever connects mechanically through cables
and teleflex controls to the fuel control unit.
The levers control the opening and closing of
the fuel control units from off (no fuel flow)
to the idle throttle setting. The levers also
connect mechanically with the hydraulic sup-
ply valves. Closing of a HP fuel cock simul-
taneously isolates the respective engine’s
hydraulic fluid supply.
A cam and spring at the OFF (0°) and ON (20°)
positions of each HP fuel cock control lever me-
chanically lock the levers in either position.
Before moving the lever, the knob must be pulled
out to unlock it. The lever automatically locks
once it reaches the OPEN or CLOSED positions.
Microswitches within each lever control power
to the engine igniter units. In OFF, a circuit
opens to remove power to the igniter unit. In
ON, the switch closes to supply power to the
respective unit.
A red warning light is above the ON position
of each HP fuel cock control lever. The light
will become lit in combination with the fire
warning system as a reminder to close the re-
spective cock.
Engine Synchronizer
The engine synchronizer provides synchro-
nization of the engines. Using the three posi-
t i o n E N G S Y N C s w i t c h ( F i g u r e 7 - 1 3 ) ,
synchronization of either the low pressure fan
(N
1
) or the high pressure turbine (N
2
) speeds
can be selected in the cockpit. The left engine
(No. 1) is the master engine and the right en-
gine (No. 2) is the slave.
The system compares either the N
1
or N
2
speeds of the engines. The synchronizer pro-
cesses speed signals from each engine and
provide a trim signal to the electronic engine
computer of the slave engine to reduce an
speed difference.
Synchronization has limited authority and can
occur only when speed differential is within
the authority range. The maximum authority
range is ±2.5 % N
2
at throttle midrange; au-
thority range decreases as engine speed in-
c r e a s e s o r d e c r e a s e s f r o m t h e t h r o t t l e
midrange. The synchronizer has no effect at
the full throttle settings.
The OFF position of the switch removes the
DC power from the synchronizer; the N
1
and
N
2
positions select the spool that will be used
for synchronization. Operation of the syn-
chronizer requires both engine computer
switches to be in the AUTO position.
With APR armed the synchronizer is inoper-
ative. When a synchronizer is switched off, the
N
1
rpm indicator shows N
1
rpm compensated
for the thrust of the engine. When the syn-
chronizer is switched to N
1
or N
2
the N
1
rpm
indicator shows the N
1
rpm.
The engine synchronizer system uses 28 VDC
from the PE busbar.
ENG SYNC
N1
OFF
N2
Figure 7-13. Engine Synchronizer Switch
Summary of Contents for 800 XP
Page 4: ......
Page 6: ......
Page 10: ......
Page 104: ......
Page 124: ......
Page 126: ......
Page 156: ......
Page 158: ......
Page 160: ......
Page 170: ......
Page 172: ......
Page 174: ......
Page 184: ......
Page 186: ......
Page 198: ......
Page 200: ......
Page 202: ......
Page 222: ......
Page 264: ......
Page 266: ......
Page 268: ......
Page 276: ......
Page 278: ......
Page 280: ......
Page 290: ......
Page 292: ......
Page 310: ......
Page 312: ......
Page 314: ......
Page 328: ......
Page 338: ......
Page 340: ......
Page 342: ......
Page 352: ......
Page 354: ......
Page 356: ......
Page 378: ......
Page 412: ......
Page 414: ......
Page 416: ......
Page 474: ......
Page 476: ......
Page 478: ......
Page 486: ......
Page 500: ......
Page 502: ......
Page 504: ......