Hawker 800 XP, Pilot Training Manual

Page: 335 / 504

QNH—MB
970 975 980 985 990 995 1,000
IN. Hg 28.64 28.79 28.94 29.09 29.23 29.38 29.53
CORRECTION
—
FEET
+ 1,500 + 1,350 + 1,250 + 1,100 + 950 + 800 + 650
QNH—MB
1,005 1,010 1,015 1,020 1,025 1,030 1,035
IN. Hg 29.68 29.82 29.97 30.12 30.27 30.41 30.56
CORRECTION
—
FEET
+ 550 + 400 + 250 + 100 0 – 150 – 300
TAKEOFF
Before beginning the takeoff, the MAIN AIR
VLV switches must be set to CLOSE. Check
that both MAIN AIR VALVE annunciators are
extinguished. Check that the F/DK VLV switch
is set to CLOSE. Check that the PRESSN
switch is set to AUTO.
AFTER TAKEOFF
As soon as practicable after takeoff, position
the MAIN AIR VLV switches to OPEN. Check
that MAIN AIR VALVE annunciators are ex-
tinguished. Check that the DUCT OVHT
↑
annunciator remains extinguished. Adjust the
cabin RATE of change knob to obtain the de-
sired rate of climb appropriate to the top of
climb height.
If the airplane fails to pressurize during the
climb, it may be due to an auto mode mal-
function. Select the PRESSN switch to OVRD;
this will ensure that the fan-oprated venturi,
normally operating on the ground to hold the
outflow valves open, is switched off.
In the event of cabin altitude not being con-
trolled satisfactorily by the cabin pressure con-
trol, turn the MANUAL CABIN ALTITUDE
CONTROL slightly in the INCREASE direc-
tion. The PRESSURIZATION CONTROL
lever should then be turned to the GROUND
TEST position after which the MANUAL
CABIN ALTITUDE CONTROL can be used to
attain the required cabin altitude.
DURING FLIGHT
Check that the cabin altitude and temperature
are maintained satisfactorily. Crew compart-
ment temperature may be increased indepen-
dently of the cabin by operation of the F/DK
VLV switch.
DESCENT
At the start of descent, set the cabin pressure
control according to Table 12-1 for the desti-
nation airfield. Adjust the cabin RATE of
change knob to give the desired rate of descent.
This should not exceed 300 ft/minute.
BEFORE LANDING
The cabin altitude setting for landing depends
upon the destination barometric pressure (QNH).
Apply the correction given in Table 12-1 for the
appropriate barometric pressure (QNH) to the air-
field elevation. Then set that value on the outer
scale of the CABIN CONTROLLER.
Close the main air valves before the aircraft
descends below 250 feet to reduce engine
12-7
FOR TRAINING PURPOSES ONLY
HAWKER 800 XP PILOT TRAINING MANUAL
FlightSafety
international
Table 12-1. CABIN ALTITUDE SETTING FOR LANDING