Back to center instrument panel.
The MD80 has a landing gear that is mechanically actuated and hydraulically operated.
Normally actuated by a landing gear handle, the gear may be raised or lowered
by pressure from the right hydraulic system or by pressure transferred from the
left hydraulic system through the power transfer unit. When retracted, the gear
is fully enclosed by doors. If the right hydraulic system fails, the gear can
be mechanically released to free fall to the extended locked position. An
electrically monitored visual/aural indicating and warning system provides
indication of gear and brake system status.
Gear handle must be pulled out of detent at UP and DOWN before it can be moved.
To prevent inadvertent retraction, handle is locked in down position until nose
gear strut extends and moves ground shift mechanism.
GEAR HANDLE RELEASE button provides a means of bypassing antiretraction release
mechanism to allow landing gear handle to be raised in event of ground shift
system malfunction after takeoff.
Gear door open
Comes on to indicate main gear doors not fully closed with gear handle DOWN or
emergency extension lever raised.
- - indicates that respective gear is DOWN and locked with gear
handle down or emergency gear extension lever raised.
- - indicates that gear is not DOWN and locked with gear handle down or emergency
extension lever raised.
- - For main gear doors - door not latched closed with gear handle UP.
- - Landing gear in transition or not in agreement with gear handle.
- Indicates gear up and locked and, for main gear, door latched closed,
with gear handle UP.
||Gear light (alternate installation).
Upper: RED with black lettering.
Lower: Black with green lettering.
||Emergency gear extension lever.
Mechanically releases main gear door latches, nose gear over-center lock and
places gear hydraulic system in bypass condition allowing gear to free-fall
and lock into position. The main gear doors will remain open.