A-A
LOWER RUDDER ALIGNED WITH THE INDEX TAB (VIEW FROM THE REAR)
Upper Rudder Power Control Package Adjustment
Figure 501 (Sheet 2)

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A
747-400
MAINTENANCE MANUAL

 S 865-006
 WARNING: MAKE SURE THAT PERSONS AND EQUIPMENT ARE CLEAR OF ALL CONTROL
_______ SURFACES BEFORE YOU SUPPLY HYDRAULIC POWER. AILERONS, RUDDERS, ELEVATORS, FLAPS, SPOILERS, LANDING GEAR AND THRUST REVERSERS CAN MOVE QUICKLY WHEN YOU SUPPLY HYDRAULIC POWER. THIS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
 (5)  
Supply systems No. 1, 2, 3 and 4 hydraulic power (Ref 29-11-00/201).

 D.
Adjust the Upper Rudder Power Control Package

 S 865-007
 (1)  
Make sure the lower rudder is in the neutral position:

 (a)  
Adjust the rudder trim indicator to the neutral position.

 (b)  
Shake the rudder pedals to put the cam of the feel, centering and trim mechanism in the detent.

 (c)  
Make sure the rudder position indicator on the EICAS flight controls maintenance page shows 0 degrees.

 (d)  
Make sure the trailing edge of the lower rudder is in the width of the index tab on the index plate.

 S 825-008
 (2)  
If the lower rudder is not in the neutral position, adjust the lower rudder PCAs (Ref 27-21-16/501).

 S 835-009

 (3)  
Examine the adjustment of the upper rudder:

 (a)  
Make sure the servo unit for the upper ratio changer actuator is in the retracted position.

 NOTE: The servo unit is in the retracted position when the
____ length from the centers of the attachment bolts is 5.202-5.212 inches.
 (b)  Make sure the trailing edge of the upper rudder aligns with the trailing edge of the lower rudder in the limit of 0.20 inches.
 S 825-032
 (4)  
If the upper and lower rudders do not align in the limit, adjust the control rod for the upper rudder power control module:

 (a)  
Measure the distance between the trailing edges of the upper and lower rudders.

 (b)  
If the distance between the trailing edges of the rudders is less than 1.00 inch, adjust the control rod: 1) Loosen the two checknuts on the input control rod. 2) Turn the control rod until the trailing edges of the

 rudders align in the limit.
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MAINTENANCE MANUAL

 (c)  If the distance between the trailing edges of the rudders is more than 1.00 inch, adjust the control rod: 1) Put the FLT CONTROL HYD POWER - TAIL switches No. 1 and 3
 on the P461 Pilot's Overhead Maintenance Panel in the SHUTOFF position.
 2)  Open these circuit breakers on the P180 DC Power
 Distribution Panel and attach DO-NOT-CLOSE tags:
 a) 180H8 ELEV/RUD VLV SYS 1
 b) 180H23 ELEV/RUD VLV SYS 3

 3)  Loosen the two checknuts on the control rod.
 4)  Remove the clevis bolt that connects the aft end of the control rod to the summing lever for the power control module.
 5)  Turn the aft rod end and the rod assembly in the same direction to adjust the length of the rod.
 NOTE: A one-half turn of the rod end or the rod will move
____ the trailing edge of the rudder approximately
 1.03 inch.
 a) Decrease the length of the control rod to move the rudder left. b) Increase the length of the control rod to move the rudder right. 6) Put the rod end in its position in the summing lever.
 CAUTION: DO NOT TIGHTEN THE LARGER BOLT AFTER YOU TIGHTEN THE
_______ NUT. THE NUT AND THE SMALLER BOLT WILL BECOME LOOSE.
 7)  Install the clevis bolt, washer and nut to attach the control rod to the summing lever: a) Tighten the larger bolt to 50-65 pound-inches more than
 the run-on torque. b) Tighten the nut to 12-15 pound-inches more than the run-on torque.
　
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