FLIGHT CONTROLS
Description
Aircraft Operations Manual
8.1
PAGE
3
The autopilot rudder servo drive is mechanically
linked to the rudder control system.
Rudder Limiter System
The rudder control system includes a rudder limiter
control unit that controls a rudder limiting mecha-
nism to prevent overload conditions as a result of
excessive rudder pedal displacement or excessive
control forces on the rudder at high speed.
The rudder limiting system provides restrictions
within following speed ranges:
−
At airspeeds below 150 kts, the system permits
full range of movement for the rudder.
−
At airspeeds between 150 and 200 kts the sys-
tem limits rudder deflection to 15 deg. in either
direction.
−
At airspeeds above 200 kts the system limits rud-
der deflections to 6.3 deg. in either direction.
In a malfunction of the system the RUDDER LIMIT
light on the Central Warning Panel comes on. The
Rudder Limiter Control Unit will consider one of the
following cases as a system malfunction: power
loss, limiting mechanism fails to enter proper posi-
tion for corresponding airspeed, a failure in the
speed sensors or excessive rudder command for
corresponding airspeed due to mechanical failure.
The rudder limiter system can be overridden by set-
ting the RUDDER LIMIT switch to the OVRD posi-
tion. By setting the RUDDER LIMIT switch to
OVRD the rudder limiting mechanism will be re-
tracted by the override actuator enabling full range
of movement for the rudder at any airspeeds. The
RUDDER LIMIT light will then persist until the air-
speed is below 140 kts, where actual position of the
limiting mechanism will correspond with the air-
speed thus extinguishing the warning light.
2.4
Flaps
There is a single, slotted flap on each wing. The
flaps are mechanically interconnected and are oper-
ated by hydraulic power and controlled with a han-
dle on the center pedestal.
The flaps can also be powered by hydraulic hand
pump pressure. Ref. AOM 10.1 and 10.2.
To prevent flap damage due to excessive air loads,
a blow
−
back protection is incorporated in the hy-
draulic system.
There are four handle ”detents”, designated, 7, 15,
20 and 35, respectively. Cockpit indication is by way
of a dual pointer instrument, with a white ”band” at
each setting.
The actual flap deflection achieved at each setting
varies with airspeed. At the maximum airspeed al-
lowed for a setting the air loads on the flap surfaces
make the pointers stop at the ”upper end” of the
white band, whereas on ground they may stop clos-
er to the ”lower end”. The white band thus indicates
a ”range”, to accommodate the flexing of the flap
surfaces at different airspeeds.
A left flap position sensor supplies signals used for:
−
Left flap position indicator pointer in cockpit
−
Position feedback for flap operation.
−
Takeoff configuration warning (CONFIG)
−
Flight recorder.
−
Left stall warning channel.
A right flap position sensor supplies signals used
for:
−
Right flap position indicator pointer in cockpit
−
Landing configuration warning (CONFIG)
−
Right stall warning channel.
A flap position signal for the GPWS is also supplied
directly from the flap control unit.
If there is a malfunction in the flap electrical control
system the FLAPS light on the CWP illuminates.
A flap control system TEST lamp and a TEST
switch are installed on the overhead panel.
2.5
Gust locks
The gust lock is controlled with a handle on the cen-
ter pedestal in the cockpit. The system locks the
elevator and aileron controls mechanically and the
rudder electrically. Either of the control columns
must be pushed forward in order to get the elevator
gust
−
lock into grip.
With the gust lock engaged, power lever movement
is limited to prevent the aircraft from taking off with
the controls locked.
Dec 01/20
