BOMBARDIER BD-100-1A10, Руководство по эксплуатации

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POWERPLANT
Sep 13/2004 Flight Crew Operating Manual Volume 2
REV 1 CSP 100-6
18-01-21
THRUST REVERSER SYSTEM (Cont)
REVERSE THRUST OPERATION
When reverse thrust is desired, the thrust levers are drawn aft to the IDLE position, where the thrust reverser levers may
be lifted, thus allowing the main thrust levers to be pulled further rearward to the REV soft detent. This rearward movement
signals the FADEC (via the RVDTs) and the thrust reversers (via the microswitches in the TQA) that thrust reverser de-
ployment has been commanded. Once in the REV detent, it is unnecessary to hold the thrust reverse levers up, as they stay
in place until the pilot selects forward operation. Interlock balks will prevent movement of the levers rearward beyond REV
until the thrust reverser deploy switches provide feedback that the thrust reverser doors are fully deployed. During the de-
ployment sequence, a white REV icon is displayed on the EICAS, and N
1
target and bug are removed from the display.
Once the doors are fully deployed, the REV icon changes to a green color, and the interlock baulk is released. This will
allow for thrust lever modulation between the REV and MAX REV positions. N
1
target and bug are set to the maximum
reverser N
1
setting.
To stow the thrust reversers, the main thrust levers are moved forward to the IDLE position. As the lever move between
the REV and IDLE positions, the thrust reverser levers will return to their forward thrust position. Interlock balks will pre-
vent movement of the main thrust levers forward beyond IDLE until the thrust reverser stow switches provide feedback
that the doors have completely closed. During the stow phase, the REV icon will go from green to white, and the N
1
target
and bug are removed from the display. Once the doors are fully stowed, the REV icon will disappear, and the N
1
target and
bug will reset to the takeoff setting. Also, the forward interlock baulk will be removed, allowing for forward
thrust modulation above idle thrust.
Thrust reverser operation of each engine is independent of the other engine. If the FADEC senses that a thrust reverser door
is unlocked in flight, the FADEC will limit engine thrust to idle, irrespective of thrust lever position. It will also post
a L (R) REVERSER UNSAFE (W) CAS message. If the main thrust levers are pulled rearward to the REV position when
the aircraft is not on the ground (no WOW or wheel spinup signal), the doors will not be unlocked, and an amber REV icon
is illuminated inside the N
1
display. This caution signal is removed if the levers are restored to IDLE or forward while in
the air.
ISOLATION CONTROL UNIT
The isolation unit controls the hydraulic system pressure to the thrust reverser system.
DIRECTIONAL CONTROL UNIT
The directional control unit controls hydraulic pressure to the upper and lower door actuators to deploy force.
A pressure switch sends a signal to the directional control unit. The directional control unit control also sends a signal to
the upper and lower door actuators causing an overstow of the thrust reverser doors to enable unlatching of the primary
locks.
The unit contains a directional control valve that is controlled by a solenoid valve. The solenoid valve is controlled from
thrust lever microswitches, WOW and wheel spinup signals. When the solenoid is energized, a deploy valve opens allowing
hydraulic pressure to sequentially release the two primary locks.
Through the WOW or wheel spinup signal, two tertiary locks (prevents uncommanded thrust reverser deployment) release
and allows the directional control valve to the deploy position.
As the aircraft decelerates, the maximum N
1
is reduced which limits thrust reverser authority and also helps prevent thrust
reverser controllability problems.