cargo compartment.
2) Disconnect from the bellcrank, the pushrod which connects bellcrank to torque tube (Detail A).
3) Using a strap wrench, rotate master latch lock torque tube to retract the latch lock sectors and open the pressure relief doors.
(c) Bypass jammed latch actuator or mechanism (if applicable). 1) Remove four access panels from lower edge of door and two midway up the door.
2) Disconnect from the bellcranks, the pushrods which connect each of the four lower latch bellcranks and the two midspan latch bellcranks to the latch torque tubes (Details B and F).
3) Pull out on midspan latch bellcrank to unlatch midspan latch.
4) Position latch mechanism pushrods (4 places) horizontally then, using a soft mallet, move pushrod inboard by gently tapping pushrod, and check that latch bellcranks rotate to unlatch door.
(d) Bypass jammed hook actuator or mechanism (if applicable). 1) Remove forward and aft access panel from lower edge of door.
2) At the forward and aft access panels on the forward door and only the forward access panel on the aft door, disconnect from the bellcranks, the pushrods which connect hook bellcranks to hook torque tube (Detail C).
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3) At the aft access panel on the door, it is necessary to cut either the adjustable rod end bearing of the pushrod or the bolt which connects the pushrod to the hook bellcrank to disconnect the puchrod.
4) Using a strap wrench, rotate each bellcrank to unhook the door.
(e) Bypass jammed lift actuator or mechanism (if applicable).
WARNING: IF LATCHES AND HOOKS ARE OPEN, DOOR WILL SWING
_______ OUTWARD TO A VERTICAL POSITION WHEN DOOR LINKS ARE DISCONNECTED. BE PREPARED TO CONTROL OUTWARD MOVEMENT OF DOOR.
1) Disconnect swivel clamp from rotary actuator arm to provide slack in conduit.
2) For the forward actuator at the aft door, disconnect the two clamps to loosen the conduit.
3) Disconnect from door link support fittings, the links which connect lift actuator arms to door (Detail D).
NOTE: Access to links from outside the airplane is gained
____ through pressure relief door cutouts.
4) Using sling used to install the door, raise door to full open position and support as required.
(f)
After bypassing jammed actuator or mechanism, continue electrical operation of door as described in the "Open and close door electrically" paragraph.
(6)
Close door with a jammed actuator or mechanism.
(a)
Operate door electrically as described in the "open and close door electrically" paragragh until jammed actuator or mechanism stops door operation. Place door control switch off.
NOTE: After bypassing jammed actuator or mechanism, closing
____ can be completed electrically as described in the "open and close door electrically" paragraph.
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(b) Bypass jammed lift actuator or mechanism (if applicable).
1) Attach sling used to install door. Hoist door upward to relieve preload on door lift actuating mechanism.
2) Disconnect torque tube from forward and aft rotary actuators or if rotary actuactor is jammed component in system, remove rotary actuator (Ref 52-34-03).
3) Lower door and hold in closed position.
(c) Raise and stow the master latch lock handle in its recess and check that cargo door caution message on the upper EICAS display goes out.
NOTE: A visual check that pressure relief doors are closed
____ to the normal unpressurized condition (top of door up to
0.50 inch inboard of door skin) will verify that cargo door latches are closed and locked.
CAUTION: DO NOT CLOSE THE CARGO DOORS WHEN THE MANUAL
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