S 865-097

 (37)
 Close the 7G26 NOSE GR STRG ALTN circuit breaker on the P7 Overhead Circuit Breaker Panel.

 K.
Test Towing Provisions

 S 495-098
 (1)  
Install the rig and tow pin NS-5 at the nose gear summing mechanism (Fig. 502).

 S 715-099

 (2)  
Do a check of the nose gear steering collar:

 (a)  
Move the upper torsion link counterclockwise to move the nose gear collar 10 to 20 degrees from the neutral position.

 (b)  
Make sure that the collar turns freely.

 NOTE: Between 10 to 20 degrees the steering metering
____ valve's compensator pressure in the steering actuators may overcome manual force and the collar will start to turn by itself until it is hardover CCW (CW for CW collar rotation test).
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 32-51-00
 ALL  ú ú 03 Page 524 ú Feb 18/02
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 (c)  If this happens do these steps: 1) Remove the pressure from hydraulic system No. 1. 2) Hold the tiller handle in the hardover position.
 WARNING: IF THE TILLER HANDLE IS NOT HELD IN THE HARDOVER
_______ POSITION, THE GEAR CAN ROTATE RAPIDLY TO A CENTERED POSTION WHEN TOW PIN IS REMOVED, CAUSING POSSIBLE INJURY TO PERSONNEL IN THE WHEEL SWING PATH.
 3) Remove the rig and tow pin NS-5.
 4) Pressurize the hydraulic system No. 1.
 5) Slowly permit the tiller handle to return to neutral.
 6) Install the rig and tow pin NS-5.

 S 715-100
 (3)
Repeat the above check but move the upper torison link clockwise.

 (a)  
Make sure the results are the same.

 S 865-101
 (4)  Move the nose gear collar to the neutral position.
 S 865-145
 WARNING: IF NOSE WHEELS ARE NOT STRAIGHT-FORWARD, THE GEAR CAN RAPIDLY
_______ TO A CENTERED POSTION WHEN TOW PIN IS REMOVED, CAUSING POSSIBLE INJURY TO PERSONNEL IN THE WHEEL SWING PATH.
 (5)  
Remove the rig and tow pin NS-5.

 L.
Restore Airplane to Normal

 S 865-103
 (1)  
Move the gear handle to the DN position.

 S 865-104

 (2)  
Remove system No. 1 hydraulic power (AMM 29-11-00/201).

 S 415-105

 (3)  
Install the nose gear torsion link apex bolt (Fig. 503)

 (a)  
Remove the holding tool from the torsion link.

 (b)  
Place the upper torsion link end into the lower torsion link end fork.

 (c)  
Lubricate the apex bolt shank and threads with grease.

 (d)  
Insert the apex bolt and screw into the threaded bushing.

 (e)  
Tighten the bolt hand tight and install the quick-release pin.

 (4)  
Install the left forward ceiling panel in the passenger compartment.

 (5)  
Remove all test equipment.

 S 415-106
 S 085-107
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 32-51-00
 ALL  ú ú 03 Page 525 ú Feb 18/02
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 S 865-108
 (6)  On the P461 Pilot's Overhead Maintenance Panel, put the FLT CONTROL HYD POWER - TAIL VALVE switches No. 1, 2, 3, and 4 in the NORMAL position.
 S 865-109
 CAUTION: FAILURE TO OPEN THE CIRCUIT BREAKER BEFORE PERFORMING
_______ THE FOLLOWING PROCEDURES CAN RESULT IN DAMAGE TO EQUIPMENT OR EXCESSIVE EQUIPMENT OPERATING TIME.
 (7)  
Close the following circuit breakers:

 (a)  
P7 Overhead Circuit Breaker Panel
 1) 7G23 BODY GR STRG ARM AC
 2) 7G24 BODY GR STRG ARM DC

 (b)  
P180 DC Power Distribution Panel
 1) 180E7 ELEV/RUD VLV SYS 2
 2) 180H8 ELEV/RUD VLV SYS 1
 3) 180E22 ELEV/RUD VLV SYS 4
 4) 180E23 ELEV/RUD VLV SYS 3
　
中國(guó)航空網(wǎng) www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機(jī)維護(hù)手冊(cè) 起落架 LANDING GEAR 8(7)