2-9. ENTRANCE AND EXIT PROVISIONS.
Two keys are provided in the loose tools
and equipment bag. Both keys fit the locks
on the cabin door, emergency hatch,
tailcone access door, and the right and left
nose avionics compartment doors.
a. Cabin Door.
Structural damage may occur if more than
one person is present on the airstair cabin
door at one time. The door is weight
limited to 300 pounds.
An airstair cabin door, hinged at the bottom,
provides a stairway, for normal and emergency
entrance and exit. Refer to Figure 2-8. In the closed
position, the door becomes an integral part of the
cargo door. The cabin door is provided with steps, two
of which fold flat against the door in the closed
position. A step folds down over the doorsill when the
door opens to provide a platform (step) for door seal
protection. T3 F3 A plastic-encased cable provides
a handhold and support for the door in the open
position and a convenience for closing the door from
inside. R Two plastic-encased cables provide a
handhold and support for the door in the open position
and a convenience for closing the door from inside. A
hydraulic damper permits the door to lower gradually
during opening. A rubber seal around the door seals
the pressure vessel while the aircraft is in flight. The
door locking mechanism is by either of the two
mechanically interconnected handles, one inside and
the other outside the door. When either handle is
rotated, three rotating cam-type latches on either side
of the door capture posts mounted on the cargo door.
A button adjacent to the door handle must be pressed
before the handle can be rotated to open the door. A
bellows behind the button is inflated when the aircraft
is pressurized to prevent accidental unlatching and/or
opening of the door. A placard adjacent to the window
instructs the operator that the safety lock arm is in
position around the bellows shaft that indicates a
properly locked door. Pushing the red button adjacent
mechanism. T3 F3 A DOOR UNLOCKED annunciator
on the caution/advisory panel will illuminate if the door
is not closed and all latches fully locked. R A DOOR
UNLOCKED warning light on the caution/advisory
panel will illuminate if the door is not closed and all
latches fully locked. The cabin door opening is
21.5 inches wide by 46.0 inches high.
b. Cargo Door. A swing-up cargo door, hinged
at the top, provides access for loading cargo or bulky
items. Refer to Figure 2-8. The cargo door opening is
52.0 inches wide by 52.0 inches high. After initial
opening force is applied, gas springs will completely
open the cargo door automatically. The door is
counter-balanced and will remain in the open position.
A door support rod is used to hold the door in the open
position, and to aid in overcoming the pressure of the
gas spring assemblies when closing the door. Once
closed, the gas springs apply a closing force to assist
in latching the door. A rubber seal around the door
seals the pressure vessel while in flight. The door
locking mechanism is operated only from inside the
aircraft, and is operated by two handles, one in the
bottom forward portion of the door and the other in the
upper aft portion of the door. When the upper aft
handle is operated per placard instructions, cam-type
latches (two on the forward side of the door and two
on the aft side) rotate, capturing posts mounted on the
fuselage side of the door opening. The bottom handle,
when operated per placard instructions, actuates four
pin-lug latches across the bottom of the door. A button
on the upper aft handle must be pressed before the
handle can be released to open or latch the door. A
latching lever on the bottom handle must be lifted to
release the handle before the lower latches can be
opened. These act as additional aids in preventing
accidental opening or unlatching of the door. The
cabin and cargo doors are equipped with dual sensing
circuits to provide the crew with remote indication of
cabin/cargo door security. An annunciator, placarded
DOOR UNLOCKED, will illuminate if the cabin or
cargo door is open and the battery switch is on. If the
battery switch is off, the annunciator will illuminate only
if the cabin/cargo door is not securely closed and
latched. The cabin/cargo door sensing circuit receives
power from the hot battery bus.
When operating the cargo door, ensure
that the cabin door is closed and locked.
Operating the cargo door while the cabin
door is open may damage the door hinge
and adjacent structure.
To prevent damage to the mechanism,
avoid side loading of the gas springs.
(1) Opening the Cargo Door.
1. Handle Access Door (lower forward
corner of door) Unfasten and open.
2. Handle Lift hook and move to OPEN
3. Handle Access Door Secure.