(a)
Procedure 1 (for airplanes with two SRM's P/N 285U0015-108 or later), see procedure 1 (Ref/27-21-00/524).
WARNING:_______MAKE SURE THE FLAPS ARE RETRACTED. IF THE FLAPS ARE NOT RETRACTED, THEY CAN MOVE WHEN YOU PRESSURIZE THE PITOT-STATIC SYSTEM. THIS CAN CAUSE INJURY TO PERSONS OR DAMAGE TO EQUIPMENT.
(b)
Procedure 2 (airplanes with any combination of SRM part numbers installed), supply a 3.37-3.52 psig pressure (363-371 knots) to the pitot port of the top right and the top left pitot probes (Ref 34-11-00/201).
(c)
If the trailing edge of the rudder moves more than 0.06 inch, adjust the input rod for the rudder ratio changer. 1) If the rudder moved in a right direction when you extended
the rudder ratio servos, make the input rod shorter. If the rudder moved in a left direction when you extended the rudder ratio servos, make the input rod longer.
(d)
Large adjustment:
1) Find the switches for the FLT CONTROL HYD POWER on the pilot's overhead maintenance panel, P461: a) Put the No. 2 and No. 4 tail switches in the SHUTOFF
position.
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(e)
(f)
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747-400 MAINTENANCE MANUAL
2) Open these circuit breakers on the DC Power Distribution Panel, P180, and attach DO-NOT-CLOSE tags: a) 180E7, ELEV/RUD VLV SYS 2 b) 180E22, ELEV/RUD VLV SYS 4
3) Loosen the clamp bolt on the input rod.
NOTE: This is at the rudder ratio changer end of the input
____
rod.
4) Loosen the locknuts on the input rod. 5) Disconnect the input rod from the input crank of the rudder ratio changer. 6) Turn the rod end or the knurled adjuster nut.
NOTE: One turn of the rod end and the knurled adjuster nut
____ together is equivalent to 2.1 inches of travel at the rudder trailing edge. One turn of the rod end (when the knurled adjuster nut does not move) is equivalent to 1.6 inches of travel at the rudder trailing edge.
7) Connect the input rod to the input crank with the bolt, washer, and nut.
8) Remove the DO-NOT-CLOSE tags and close these circuit breakers on the P180 panel: a) 180E7, ELEV/RUD VLV SYS 2 b) 180E22, ELEV/RUD VLV SYS 4
9) Find the switches for the FLT CONTROL HYD POWER on the pilot's overhead maintenance panel, P461: a) Put the No. 2 and No. 4 tail switches in the NORM
position.Small adjustment: 1) Loosen the clamp bolt on the input rod.
NOTE: This is at the rudder ratio changer end of the input
____
rod.
2) Loosen the locknuts on the input rod. 3) Turn the knurled adjuster nut.
NOTE: One turn of the knurled adjuster nut is equivalent
____ to 0.5 inches of travel at the rudder trailing edge.
Tighten the locknuts on the input rod.
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747-400 MAINTENANCE MANUAL
(g)
If procedure 1 was used to extend the actuator, push the LSK that is adjacent to END TEST> on the CDU.
(h)
If procedure 2 was used to extend the actuator, slowly release the pressure from the pitot static system (Ref 34-11-00/201).
S 825-046
(3) Do the steps above until the rudder moves less than 0.06 inch when you extend the rudder ratio servos.
S 225-018
CAUTION:_______MAKE SURE THE ROD ENDS ARE ENGAGED CORRECTLY. IF THE ROD ENDS ARE NOT ENGAGED CORRECTLY, THE ROD CAN BREAK.
(4)
Make sure you can see the threads of the rod end through the inspection holes in the input rod.
S 225-047
(5)
Make sure you cannot see more than 10 threads adjacent to each of the locknuts.
S 435-048
(6)
Tighten the clamp bolt on the input rod to 80-110 pound-inches.
S 865-019
(7)
If the rudder ratio servos are not retracted, do one of the two subsequent procedures to retract the servos.
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