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A
757 MAINTENANCE MANUAL
D. Install the Rudder Ratio Changer Support Clevis
S 422-100
(1)
Install the RRCA support fitting, shims, nut and washer.
S 412-101
(2)
Connect the RRCA
(a)
Connect the RRCA to the support clevis.
(b)
Connect the RRCA to the left ratio changer crank.
E.
Adjust the RRCA Support Clevis Shims
S 862-102
(1)
Supply pressure to the left hydraulic system (Ref 29-11-00/201).
S 862-103
(2)
Open these circuit breakers on the overhead panel, P11, and attach DO-NOT-CLOSE tags:
(a)
11D18 or 11G10, RUD RATIO
(b)
11C7, CSEU 1L-DC
or FLT CONT ELEC 1L DC
(c)
11C9, CSEU 2L-DC
or FLT CONT ELEC 2L DC
(d)
11G18, CSEU 1R-DC
or FLT CONT ELEC 1R DC
(e)
11G28, CSEU 2R-DC
or FLT CONT ELEC 2R DC
S 492-104
(3)
Install the rig pin R3.
S 862-105
(4)
Put the RRCM to the TEST position.
S 822-106
(5)
Adjust the LVDT until the rig pin R5 can be installed with a loose fit.
(6)
Measure and write down the actuator extension length (Fig. 201).
(7)
Adjust the LVDT to fully extend the RRCA.
S 972-109
(8)
When the RRCA is at full stroke (at its maximum extension), measure and write down the actuator extension length (Fig. 201).
S 972-107
S 822-108
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
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A
757
MAINTENANCE MANUAL
S 972-110
(9) Compare the first actuator extension measurement with the second
actuator extension measurement.
(a) The second actuator extension measurement must be 0.02-0.04
inches more than the first actuator extension measurement.
(b) Add or remove shims until the second actuator extension
measurement is 0.02-0.04 inches (0.5-1.0 mm) more than the
first actuator extension measurement.
NOTE: You must add shims to increase the stroke measurement____
of the second actuator.
S 012-111
(10) Disconnect the rudder ratio changer actuator.
(a) Disconnect the RRCA from the left ratio changer crank.
(b) Disconnect the RRCA from the support clevis.
S 022-112
(11) Remove the support clevis.
(a) Add corrosion poreventative compound to the shims.
S 422-114
(12) Install the support fitting, shims, nut and washer.
S 412-113
(13) Connect the rudder ratio changer actuator.
(a) Connect the RRCA to the Support Clevis.
(b) Connect the RRCA to the left ratio changer crank.
1) Make sure rig pin R5 can be easily installed.
2) Make sure there is not more than 0.04 inch (1.0 mm) of RRCA
stroke beyond the rig position.
S 822-115
(14) Adjust the Rudder Ratio Changer Mechanism (Ref 27-21-00/501).
F. Put the Airplane Back to Its Usual Condition
S 862-118
(1) Remove the DO-NOT-OPERATE tags and move the FLT CONTROL L, R, and C
switches on the P61 panel to ON.
S 862-117
ú CAUTION: IF THE RRCM TEST SWITCH IS NOT IN ITS "NORMAL" POSITION,_______
ú THE AMBER "RUDDER RATIO" LIGHT WILL COME ON. THIS WILL
ú PREVENT AIRPLANE DISPATCH.
(2) Make sure that the RRCM test switch is in its NORMAL position.
S 412-119
(3) Close the access panels 324AL, 324BL (AMM 06-42-00/201).
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：757 AMM 飞机维护手册 飞行操纵 FLIGHT CONTROLS 2(62)
