(3)  
After the latching crank has operated, continued rotation of the control cam transmits angular movement to the cocking crank which operates a pushrod connected to the door torque tube. Movement of the pushrod, which is resisted by the door torque tube, causes the hinge arms to rotate about the hinge arm elbow pins and shift the door inboard. The forward end of the door angles inboard, and the aft end, remaining in the same relative position, moves slightly inboard and forward. As the door approaches the cocked position, the upper and lower hinge link covers release the spring-loaded hinge flaps allowing them to be pushed inward.

 (4)  
The door is swung outward through the opening by means of the assist handle. The door arc is controlled by the guide arm roller pin tracking in the guide plates as the hinge arms pivot about the body torque tube. As the door approaches the open position, the interior handle rotates clockwise due to a change in the relative position of the hinge arms which cause the cocking crank and control cam to rotate. A snubber in the body torque tube limits door actuating speed in both opening and closing sequences. A hold-open assembly in the body torque tube is engaged when door is fully open to prevent the door from contacting the fuselage or from leaving the open position.

 (5)  
The door is opened from outside the airplane by pushing the latch button and pulling the butterfly handle out from its recess in the door outer skin. The outward movement of the exterior handle engages the exterior handle shaft with the interior handle shaft by means of a clutch collar.

 (6)  
After extending the exterior handles, the handles are then rotated clockwise 180 degrees to unlatch and move the door to the cocked position. The handle must be stowed in this position (180 degrees from door closed position) before the door is pushed out of the cocked position into the full open position. As the exterior handle is rotated to the cocked position the interior handle also moves from door closed to door cocked position. Exterior handle rotation results in door mechanisms functioning the same as for interior handle rotation.

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 ALL  ú ú 02 Page 14 ú Oct 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

 (7)  
The door is closed from inside the airplane by lifting or pushing the hold-open release lever and swinging the door through the opening to the cocked position. This causes the interior handle to rotate counterclockwise. With door in cocked position, clockwiserotation of the interior handle causes the hinge arms to rotate about the hinge arm elbow pins and shift the door to the closed position. As the hinge arm elbow pins shift outboard, the door pivots on the hinge arm about the hinge arm elbow pins and brings the door into the door opening. After the door is centered, continued rotation of the interior handle operates the upper and lower latch torque tubes which engage the latch rollers in the latch cams and unfolds the upper and lower gates outward. Engagement of the latch rollers opens the door warning switch and extinguishes the annunciator light on the flight engineer's panel.

 (8)  
The door is closed from outside the airplane by lifting or pushing the hold-open release lever and swinging the door through the opening to the cocked position. With door in cocked position, the exterior handle is unstowed and rotated counterclockwise until the door is closed and latched.

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 ALL  ú ú 02 Page 15 ú Oct 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 FAULT ISOLATION/MAINT MANUAL
MAIN ENTRY DOORS
COMPONENT  SHT 102 FIG.  QTY  ACCESS/AREA  REFERENCE 
ARMS - DOOR NO. 1 GUIDE  2 BOTTOM OF BODY HINGE TORQUE TUBE  52-11-04 
ARMS - DOOR NO. 1 HINGE  4 TOP AND BOTTOM OF BODY HINGE TORQUE TUBE  52-11-03 
ARMS - DOORS NO. 5 GUIDE  1 TOP OF BODY HINGE TORQUE TUBE  52-11-04 
ARMS - DOORS NO. 5 HINGE  2 TOP AND BOTTOM OF BODY HINGE TORQUE TUBE  52-11-03
DOOR - NO. 1 MAIN ENTRY, L  1  831L  52-11-01 
　
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