Learjet 60 - Thrust Reverser Assembly; Thrust Reverser Lever

Learjet 60
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Pilot's Manual
THRUST REVERSER ASSEMBLY
Each engine is equipped with a thrust reverser assembly attached to
the engine outer fan duct . When stowed, the thrust reverser fairs with
the nacelle and forms the engine afterbody . Each upper and lower
door is attached to the support structure by a four-bar linkage . Two
links are idler links and two are driver links . The driver links connect
to the
inboard and outboard actuators with an overcenter link . After
stowing
the doors, the actuators continue to drive the overcenter links
to an
overcenter position . This provides a mechanical latch to keep
the doors
stowed . This overcenter mechanism is referred to as the pri-
mary latch .
In addition to the primary latch, each
thrust reverser door is held in
the stowed position by a secondary
latch . A latch plate on each door
engages the spring-loaded
secondary latch mechanism securing the
door in the stowed
and
locked
position . During the deployment se-
quence, each secondary latch is
released by hydraulic pressure from
the deploy line .
Each assembly is equipped
with two primary latch stow switches,
two secondary latch stow switches,
and one deploy switch . The
pri-
mary latch stow switches are
used to detect the extreme
aft (locked)
position of the inboard and
outboard actuators . The
secondary latch
stow switches are used to
detect the engagement of
the
secondary
latch with the thrust reverser
doors . The deploy switch
is actuated by
one of the idler links
and detects the fully deployed
position . These
switches
provide signals to sequence the thrust
reverser operation,
control the thrust
reverser annunciators, control
the throttle balk sole-
noid and
initiate the auto stow sequence .
THRUST
REVERSER LEVER
A thrust reverser lever
is mounted piggy-back
fashion on each main
thrust lever . The thrust
reverser lever cannot be
moved out of the
STOW position unless
the associated main thrust lever
is at the IDLE
stop . Similarly, the main thrust
lever cannot be moved
from the IDLE
position when the associated thrust
reverser lever is in
the DEPLOY
and reverse thrust range .
Moving the
main thrust lever to IDLE actuates a
switch in the throttle
quadrant to signal the system
to arm if the aircraft is
on the ground .
Another
switch in the throttle quadrant is
actuated by the thrust re-
verser
lever and signals the system to stow or
deploy the associated
thrust reverser .
When both thrust reversers are fully
deployed, the thrust reverser
lev-
ers are allowed to move beyond
the DEPLOY detent into the
reverse
PM-123
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2-25
Change 3