7-19
FOR TRAINING PURPOSES ONLY
HAWKER 800 XP
PILOT TRAINING MANUAL
FlightSafety
international
A pressure switch, which operates at 6 psi, is
tapped into the air bleed pipe from the en-
gine. When the air pressure is low, the switch
operates to cause an ENG 1 (or 2) A/ICE an-
nunciator to be lit on the MWS panel.
The anti-icing valve is energized to the closed
position (with busbar energized and ENG
ANTICE switch selected to OFF), and is bi-
ased to the open position. This provides anti-
icing fail-safe operation in the event of an
electrical malfunction.
Prior to the opening of an anti-icing valve, or
during any subsequent system failure, the
pressure switch will register a low pressure
condition and the appropriate ENG A/ICE an-
nunciator will be lit at the MWS dim pre-set
level (Figure 7-16). The annunciator will re-
main lit at the dim level after the switch has
been selected to ON, until the nacelle anti-icing
air supply rises above 6 psi and the pressure
switch contacts change over. Then the an-
nunciator goes out.
However, a timer in the circuit ensures that the
annunciator will brighten to full intensity,
should the pressure switch not operate within
two seconds. The time delay also inhibits ‘nui-
sance’ flashing of the annunciator during nor-
mal system operation.
ENG ANTICE
1 ON 2
OFF
Figure 7-15. Engine Anti-ice Switch
ENG 1
A-ICE
ENG 2
A-ICE
Figure 7-16. Engine Anti-ice Annunciator
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: ......