Learjet 60 - Gear Free Fall

Learjet 60

Pilot's Manual
GEAR FREE
FALL
When the EMERGENCY
FREE FALL GEAR lever on the right side
of
the pedestal is pushed
full down (until lever latches), air pressure
from the BRAKE AIR and free
fall emergency air bottle is admitted to
the free
fall system through the lever actuated
free fall valve . The air
pressure is
directly applied to an uplock
actuator for each inboard
main gear
door, a nose gear uplock actuator,
the door selector valve,
the gear selector
valve, and a hydraulic pressure
shunt . The uplock
actuators open the gear
doors and release the nose gear
uplock allow-
ing the gear to free fall .
The gear and door selector
valves are posi-
tioned
to "down" to prevent
inadvertent gear retraction . The
hydraul-
ic pressure
shunt diverts hydraulic
system pressure to a
hydraulic
return line .
Full gear extension should
occur within 15 seconds with
a
complete loss of
hydraulic pressure . When
the landing gear is
down
and locked, the
three green LOCKED DN
lights will illuminate
. The
two outboard red
UNSAFE lights will remain
illuminated after
exten-
sion due to the inboard
main gear doors
remaining open . When
emer-
gency gear free
fall is selected, the
EMERGENCY FREE
FALL GEAR
lever must be returned
to the "up" position
in order to
retain BRAKE
AIR bottle pressure
for emergency
braking (hydraulic
system failure)
or
in order to allow
the hydraulic shunt
to reposition,
allowing the
hydraulic system to
regain pressure
(electrical malfunction)
. The
EMERGENCY FREE
FALL GEAR lever
is returned to
the "up" posi-
tion by lifting
the lever release (small
metal tab available
through the
small hole immediately
forward of the
lever) and pulling
the lever to
the full
up (latched) position
.
PM-123

3-
13
Original