22-11-00
ú ú 09 Page 19 ú Mar 15/89
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
B. Airplane speed is monitored and when within the mach tuck region, a signal is provided to drive the actuator to the retract direction. This provides an up elevator displacement to counteract the mach tuck pitch down. Actuator extension varies with speed within the mach tuck region.
13. Switches, Lights and Aural Alert Unit_____________________________________
A. The A/P disengage switches are located on the outboard horns of the pilot's control wheels. The switches disengage the A/P and reset the disengage lights and aural warning. The switch NC (normally closed) contacts are in the A/P engage circuit and the NO (normally open) contacts are in the reset circuit.
B. The Takeoff Go-Around (TO/GA) switches are located on the aft edge of each thrust lever. The switches are positioned to operate with a fingertip, while holding the thrust lever handles. Pressing either switch, initiates takeoff or go-around for both the autothrottle and the A/P-F/D, assuming the appropraite mode interlock requirements are satisfied.
C. The A/P AUTO STAB TRIM switch is located on the lower right corner of the control stand. It is a two-position switch, NORMAL and CUTOUT, which provides stabilizer trim clutch control. The switch must be in NORMAL position to permit A/P engagement and automatic stab trim operation.
D. The CONTROL COLUMN SWITCHES disconnect the output of the FCC from the stabilizer trim servo when column force is opposite to stabilizer trim. The column switching module is located below the cabin floor at the lower end of the control column. It is attached to the torque tube which connects the two columns.
E. The STAB OUT OF TRIM annunciator light on the P2 panel illuminates amber when an A/P system is engaged and a sustained stabilizer out of trim condition exists. The light will extinguish when the A/P is disengaged or the out of trim condition is nulled.
F. The ALTITUDE ALERT lights, located on the P1 and P3 panels, illuminate steady when approaching a selected altitude (between 900 and 300 feet) and a flashing light and aural alert come on when an altitude error exists (beyond 300 feet).
G. The SPEED TRIM FAIL annunciator is illuminated if both SPEED TRIM systems fail. The MACH TRIM FAIL annunciator is illuminated if both MACH TRIM systems fail. The annunictors are located on the P5 overhead panel. If a single system fails an automatic transfer is made of the second system, therefore the annunicator does not illuminate for a single failure. However, the master caution system stores in memory the single fault. Pressing the master caution system annunciator assembly turns on the SPEED TRIM FAIL or MACH TRIM FAIL and FLT CONT annunciator if a single fault exists.
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22-11-00
ú ú 08 Page 20 ú Mar 15/89
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A 737-300/400/500MAINTENANCE MANUAL
H. The AURAL ALERT UNIT provides an audio alert when approaching (option) or departing the selected altitude. The audio alert is provided from a speaker on the P5 aft overhead panel. The speaker contains a C chord generator to provide a tone when a signal is provided from the FCC.
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本文链接地址：737-300 400 500 AMM 飞机维护手册 自动飞行 AUTOFLIGHT 1(17)
