FORWARD AIRSTAIR ACTUATOR - REMOVAL/INSTALLATION
EFFECTIVITY
Standard Passenger Airplanes
1. Equipment and Materials
A. No. 1 rig pin -0.4980 +0.0005/-0.0010-inch diameter by 4.0 inches long
B. No. 2 rig pin - 0.2480 +0.0005/-0.0010-inch diameter by 2.50 inches long
C. Grease - MIL-G-23827 (Ref 20-30-21)
2. Prepare for Removal
A. Remove Drain Pan (if installed)
(1) Extend airstair to provide clearance for removing drip pan attachment fasteners (Fig. 402).
WARNING: DO NOT OPERATE THE AIRSTAIR WHEN THESE CONDITIONS OCCUR:
-YOU WILL OPERATE THE AIRSTAIR MORE THAN 3 CYCLES IN 20
MINUTES -THE WIND IS MORE THAN 40 KNOTS -THERE IS NO SUPPORT UNDER THE END OF THE AIRSTAIR WHEN
THE AIRPLANE IS ON JACKS -THE FORWARD ENTRY DOOR IS OPENED FULLY -THE AREA IS NOT CLEAR OF PEOPLE OR EQUIPMENT.
IF YOU OPERATE THE AIRSTAIR WHEN THESE CONDITIONS OCCUR, YOU CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
NOTE: Temporary access can be attained by partially retracting airstair.
(2)
Gain access to drip pan through electronic compartment access door.
(3)
Remove hose clamp and drain hose from access hatch in drip pan. Remove access hatch.
(4)
Obtain access to drip pan attachment fasteners through access hatch. Remove fasteners.
CAUTION: DO NOT ATTEMPT TO MOVE SWING ARM OUT OF WAY OR USE SWING ARM AS HANDHOLD OR SWING ARM MAY BE DAMAGED.
(5)
Retract airstair and release control before airstair door begins to close. Remove drip pan through airstair - airstair door opening on side of fuselage.
B. Open airstair circuit breakers on panel P6. Disconnect airstair electrical connector (3)
(Fig. 401).
5C8
Feb 20/92 52-61-111 Page 401
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
Forward Airstair Actuator Installation 500
52-61-111 Page 402 Figure 401 (Sheet 1) BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. Oct 20/83
500 Forward Airstair Actuator Installation
Feb 15/68 Figure 401 (Sheet 2) BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 52-61-111 Page 403
C. Disengage carriage drive pinions by moving carriage pinion disconnect lever (2) to unlocked position.
D. Manually move carriage outboard to fully extended position and move carriage pinion disconnect lever to locked position.
E. Secure carriage to rail by inserting No. 2 rig pin through extend index hole (1) in aft rail and into index slot in aft beam of carriage.
F. Secure ladders to carriage by inserting No. 1 rig pin through index hole (5) in aft beam of carriage and into index hole in ladder truck.
3. Remove Forward Airstair Actuator
A. Remove pin which attaches fork end (11) on actuator (6) to clutch release link (12) on carriage pinion disconnect mechanism.
B. Remove swing arm (7) from bracket (18) on actuator.
C. Disconnect electrical connectors of the two actuator motors (14).
D. Disconnect couplings on forward and aft line shafts (9) and remove shafts.
E. Disconnect ball screw drive shaft (17) at forward and aft end leaving shaft in actuator.
F. Remove four bolts (10)-securing actuator to carriage and remove actuator.
G. Disconnect "dog" coupling (16) on ball screw drive shaft and remove shaft from actuator.
4. Install Forward Airstair Actuator
A. Insert ball screw drive shaft (17) in actuator leaving "dog" coupling (16) disconnected.
NOTE: Apply a film of grease to splines, bores, shanks, and threads of parts prior to assembly.
B. Hold actuator in mounting position on carriage and install four attaching bolts (10).
C. Connect both ends of ball screw drive shaft (17) to adjacent gearbox (15).
D. Install forward and aft line shafts (9) connecting actuator to carriage pinions.
52-61-111 Oct 20/83 Page 404
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
E. Install the swing arm (Fig. 401):
(1)
Attach the swing arm to the bracket on the airstair actuator.
(2)
Make sure both ends of the swing arm point up.
CAUTION: DO NOT INSTALL THE SWING ARM SO THAT THE ENDS POINT DOWN. IF THE ENDS POINT DOWN THE SWING ARM AND THE WIRE CAN BREAK. THIS CAN CAUSE SPARKS, FIRE AND DAMAGE TO EQUIPMENT. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：737 AMM 飞机维护手册 舱门 DOORS(149)
