BOMBARDIER BD-100-1A10, Руководство по эксплуатации

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LANDING GEAR
Volume 2 Flight Crew Operating Manual Sep 13/2004
15-01-06
CSP 100-6
REV 1
LANDING GEAR (Cont)
NOSE LANDING GEAR
The Nose Landing Gear (NLG) consists of a twin wheel forward retracting, cantilever shock strut, and folding drag strut
that incorporates a mechanical downlock.
The major sub-assemblies of the NLG are shock strut, retraction actuator, wheel and tire, drag brace and harness assem-
blies, hydraulic hoses and taxi/landing lights.
The nose landing gear is actuated by the left hydraulic system and electrically controlled by the proximity sensor system
(PSS) which includes the proximity sensor electronic unit (PSEU) and control handle. Normal operation of the landing gear
extension and retraction system is initiated by selecting the desired landing gear position, UP or DOWN, using the landing
gear control handle mounted on the main instrument panel.
In flight, the nose gear is electronically centered by the steering control unit (SCU), and mechanically centered by centering
cams as the oleo extends with the assistance of the nitrogen filled strut and under the weight of the springs and wheel as-
semblies.
A spring-operated external lock mechanism on the drag brace mechanically locks the nose gear in the extended position.
A NLG ground locking pin can be inserted into the upper drag brace sub-assembly to prevent inadvertent unlocking while
the aircraft is on the ground.
The NLG also contains the steering manifold assembly and steering actuator which provides steering and castering func-
tions for the NLG during ground maneuvers.
With the torque link attached, the gear can only be rotated 120
°
in either direction. Attempting to rotate beyond this causes
a switch to trip, resulting in a NWS LIMIT EXCEEDED (C) CAS message and potential structural damage. In addition to
the cockpit indication, the feedback mechanism also incorporates indicator pins at approximately
±
123
°
of steering angle.
If the steering angle exceeds this value during towing while the torque links are connected, these pins are designed to yield
to indicate the need to inspect the feedback links and surrounding area as detailed in the AMM for possible damage.
For special hangar operations, the torque links may be disconnected to allow towing at any angle provided the NLG shock
strut extension exceeds 3.50 inches of chrome showing.
NOSE DOORS
The nose gear doors give aerodynamic smoothness to the fuselage when the nose landing gear is retracted in the wheel well.
The aft door is mechanically attached to the landing gear assembly and provides partial enclosure of the gear. Two control
rods attach the aft door to the nose gear shock strut. A hinge attaches the aft door to the aircraft structure.
The forward doors attach with hinges to the left and right sides of the wheel well and are mechanically linked and operated
by the nose gear system. There are two forward-door mechanisms. Each of these mechanisms has a link which operates a
bell crank and a control rod. When the nose gear is retracted, the mechanisms pull the two forward doors to the fully closed
position.
When the nose gear is down, the forward doors and aft door will remain open.