Hawker 800 XP, Pilot Training Manual

Page: 396 / 504

Revision 1 15-16
FOR TRAINING PURPOSES ONLY
HAWKER 800 XP PILOT TRAINING MANUAL
FlightSafety
international
Flap Control System
The flap selector lever is connected by a cable
to an input lever on the flap control unit. A
spring strut and a spring drum in the cable
run compensate for any movement lag (Figure
15-13).
Movement of the input lever connects hy-
d r a u l i c p r e s s u r e t o o p e r a t e a h y d r a u l i c
motor in the flap control unit. The motor
drives the transmission shafting to move
the flaps in the selected direction. The motor
is stopped automatically should a control
cable failure occur.
When the flaps reach the selected position,
the hydraulic pressure is removed from the
motor. Further movement of the flaps is ar-
rested and they are locked at the required
angle. Friction devices prevent the flaps mov-
ing away from the selected position in the
event of hydraulic failure.
A synchronizing cable circuit is provided to
prevent the occurrence of an asymmetric flap
condition. Should one flap cease to move, the
synchronizing circuit isolates the hydraulic
supply to the flap motor, the flaps stop mov-
ing and maintain the position attained at the
moment of failure.
A flap servo baulk stops additional move-
ment of the flap control unit input lever from
the landing position. The baulk is released and
the lever moved to the lift-dump position by
an interconnection with the airbrake control
when this is moved into the lift-dump position.
Airbrakes
In flight, the airbrakes must not be operated
when the flaps are extended to any position.
Lift Dump
Lift dump is to be used only when the aircraft
is on the ground.
Rudder Bias
The rudder bias switches must be ON and the
systems operative during each takeoff.
Electrical Power Supplies
The flap position indicator is powered from the
PS1(a) busbar via circuit breaker FLAP POS
(M/7) on panel DA-D.
The warning horn is powered from the PE(a)
busbar via circuit breaker HORN (K/1) on
panel DA-D.
Emergency Operation
The flaps may be operated by means of the
auxiliary hydraulic system. Using the auxil-
iary system, the flaps can be lowered to any
preset position from 0 to 45°. Lift dump and
airbrakes are not available.
The emergency flap selection is made using
the normal flap control lever. Position indi-
cation is still available as long as PS1(a) bus-
bar is energized.
AIRBRAKE CONTROL SYSTEM
A pair of airbrakes per wing are powered by
the main hydraulic system (Figure 15-15). Of
each pair, one airbrake extends from the wing
upper surface, the other one from the wing
lower surface.