G26601
Flap Limit Switch Installation 531
27-51-291 Figure 401 Feb 15/78
Page 402
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
FLAP LIMIT SWITCHES - ADJUSTMENT/TEST
1. Flap Limit Switches Adjustment
A. Prepare Flap Limit Switches for Adjustment
(1)
Connect electrical power to airplane.
(2)
Provide System A hydraulic power (Ref 27-51-0 MP).
(3)
Position flap control lever in 30-Unit detent to extend flaps, then to FLAP UP detent to retract flaps.
(4)
After flaps are fully retracted, wait 2 minutes then remove system A hydraulic power.
(5)
On circuit breaker panel P6-2:
(a)
Close TE ALT FLAP DRIVE MOTOR circuit breaker.
(b)
Close FLAP VALVES circuit breaker.
(6)
Remove inboard flap track fairings (Ref 27-51-141 R/I).
B. Adjust Flap Limit Switches
(1)
Position flap control lever to FLAP DOWN detent.
(a) Position alternate flap switch at ARM.
(2)
With flaps up measure dimension X (Fig. 501) at 4 and 5 jackscrews. Record value and label X1.
(3)
Actuate alternate flap drive switch to DOWN. Hold switch in this position until number 4 ball screw nut is an additional 29.95 to 30.11 inches from its up stop.
CAUTION: LEADING EDGE CONTROL SURFACES WILL EXTEND.
(4)
Remove switch cover from flap control unit (Fig. 502).
(5)
Adjust FLAP DOWN limit switch away from its actuating cam until switch actuates.
NOTE: Care must be taken to pre-position switch so that actuation takes place with switch body being moved away from cam.
500
Jun 20/86 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 27-51-291 Page 501
G26629G26669
Flap Jackscrew Stops 500
27-51-291 Figure 501 Feb 15/68
Page 502
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
500 Flap Limit Switch Adjustment
Aug 15/67 Figure 502 27-51-291
Page 503
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
(6)
Lockwire switch retaining nuts.
(7)
Hold the ALTERNATE FLAPS position switch in the UP position to retract the trailing edge flaps. Retract the flaps until dimension X (Detail A, Fig. 501) is 0.87 to 1.03 inch. (This is approximately equal to 1-3/4 to 2-1/4 turns between the upstop on the screw yoke and the upstop on the ball nut.) Approach this position from a flaps down position.
(8)
Adjust FLAP UP limit switch away from actuating cam until switch actuates.
NOTE: Care must be taken to pre-position switch so that actuation takes place with switch body being moved away from cam.
(9)
Lockwire switch retaining nuts.
(10)
Test flap limit switch per par. 2.
(11)
Test mach trim switch after adjustment of flaps up limit switch (Ref 22-21-31, Mach Trim Flap Switch).
(12)
Test autopilot after adjustment of flaps up limit switch (Ref\22-11-81 A/T, and 22-11-131 A/T or 22-11-132 A/T).
C. Restore Airplane to Normal Configuration
(1)
Replace switch cover on flap control unit.
(2)
Position alternate flap switch to OFF.
(3)
Position flap control lever to FLAP UP detent.
(4)
Pressurize hydraulic system A to retract leading edge devices (Ref 27-51-0 MP).
(5)
Depressurize hydraulic system A (Ref 27-51-0 MP).
(6)
Determine whether there is any further need for electrical power, if not, disconnect power.
2. Flap Limit Switches Test
A. Prepare Flap Limit Switches for Test
(1)
Connect electrical power to airplane.
(2)
Position flap control lever to FLAP DOWN detent.
501
27-51-291 Page 504 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. Aug 01/95
NOTE: Flap control lever is moved to FLAP DOWN position as a standard procedure to minimize load on flap hydraulic motor when hydraulic system A is pressurized.
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 飞行操纵 FLIGHT CONTROLS 3(74)
