Pilot’s Manual
1-6
PM-132A
CABIN ENTRY DOOR (CONT)
A cable and knob assembly is attached to the forward side of the lower
door frame. The cable and knob assembly is used to raise and lower the
lower door from inside the cabin. When closing the lower cabin door, a
secondary latch will automatically engage and hold the lower door in
position against the door seal until the lower door handle is rotated
forward to the locked position. If the handle is not rotated to latch the
door and the door is left in position by the secondary latch, the upper
door will be prevented from closing due to a pin which extends out-
board from the lower door just below the handle.
When the locking handle on the lower door is rotated forward, the
latching mechanism drives four pins into the fuselage frame, securing
the lower door. The inside and outside handles on the upper cabin door
are secured to a common shaft within the door. When either upper door
handle is rotated to the closed position, six latching pins are driven into
the fuselage structure and two pins are driven from the upper door into
overlapping halves in the lower door. There are a total of eight pins
installed in the upper door. Two of the six upper door latching pins are
driven through both the fuselage structure and through interlocking
arms on the lower door, which secure the doors together.
When the cabin entry door pins are engaged (there are twelve pins
total, eight in the upper door, four in the lower door), the door becomes
a rigid structural member. Correct pin engagement may be checked
using the small sight windows installed in the upper and lower inner
door panels. Sight windows are provided to check pin engagement for
ten of the latch pin locations, for two middle lock pins and for the lower
lock (pawl).
ENTRY DOOR ANNUNCIATIONS
All of the twelve cabin door latching pins are installed so they contact
a microswitch when the pin is fully engaged. If any of these pins do not
make contact when the upper door handle is closed, a red ENTRY
DOOR warning light is displayed on the Crew Warning Panel (CWP)
and a red ENTRY DOOR message on the Engine Indicating and Crew
Alerting System (EICAS) illuminates to provide the crew with visual
indication of cabin door security.
