Learjet 60 - Thrust Reverser Relay Box

Learjet 60

Pilot's Manual
THRUST REVERSER RELAY BOX
Two thrust reverser relay boxes
are installed in the tailcone . One box
controls the
left thrust reverser system and the other controls the
right . Inputs to each
relay box are provided from : left and right squat
switches, arming switch (throttle
quadrant), stow/deploy switch
(throttle quadrant), stow switches
(thrust reverser assembly), deploy
switch (thrust reverser assembly), and
pressure switch (HCU) . From
the input signals the relay box determines
the appropriate output sig-
nals
including : arm thrust reverser (open
isolation valve in the HCU),
deploy thrust reverser, stow thrust
reverser, initiate auto stow, limit
engine thrust to
idle (discrete signal to FADEC),
restore engine thrust
to normal (discrete signal to
FADEC), enable thrust reverser
levers
(throttle balk solenoid), annunciate
thrust reverser conditions and
in-
dicate to the takeoff monitor
whether the thrust reverser is locked
or
unlocked .
PM-123
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2-26A
Change 3