6) Fail the glide slope superflag. Observe that approach progress display remains green (G/S ENG).
7) Restore the glide slope superflag and fail the NAV superflag. Observe the AIL engage switch does not disengage.
8) Disengage autopilot, remove ground and remove radio signal.
(b) Test Altitude Rate Gain 1) Engage autopilot and observe control column in neutral. 2) Set air data computer selector switch to SLEW position. Depress (and hold down) air data computer PUSH TO TEST switch. 3) Provide centered deviation, flag retracted glide slope signal. Place mode select switch in AUTO APP position. Observe that after 15 seconds, from 0 to 2 degrees of pitch down vertical gyro is required to center control column.
4) Disengage autopilot and level vertical gyro.
5) Return ADC to normal (release button or toggle).
(c) Test Beam Displacement Gain 1) Provide centered deviation, flag retracted glide slope signal. Engage autopilot, set radio altimeter to 2000 feet, ground pitch TP-6, and observe control column in neutral.
2) Place mode select switch in AUTO APP position.
594
22-11-0 Page 528 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. May 15/81
3) Wait 15 seconds and apply 1/4-dot fly-up glide slope signal. Observe that 2.2 to 6.0 degrees of noseup gyro tilt centers control column.
4) Disengage autopilot, remove ground, level vertical gyro and remove glide slope signal.
(18) Test Stabilizer Trim
(a) Test Trim Threshold
NOTE: The mach trim actuator must be fully extended for this test. Refer to 22-21-11, Mach Trim Actuator - Adjustment/Test.
1) Set 13 units of trim on stabilizer trim wheel and open stabilizer trim three-phase ac circuit breaker. Move control column back and forth through neutral several times. a) Engage pitch axis. Hand crank the stabilizer to 3 units of trim. Check that
stabilizer out-of-trim warning light does not illuminate. b) Use the control wheel stabilizer trim (pickle) switch to return stabilizer to 13 units of trim. 2) Apply an airspeed of 350 KIAS, engage the autopilot, ground pitch TP-6, and with a VTVM observe and note ac voltage at pitch TP-10.
3) Slowly apply nosedown tilt to vertical gyro until 28 volts dc appears at pitch TP-4. With a VTVM, monitor changing ac voltage at pitch TP-10 for a minimum and final maximum voltage while tilting the vertical gyro. Observe sum of reducing voltage added to increasing voltage (which is total voltage change) is 2.2 +0.6 volts ac.
NOTE: The total voltage change must be measured. Going from 0.5 volts ac to 0.0 and from 0.0 to 1.8 volts ac is a total change of 2.3 volts ac.
4) Slowly apply noseup tilt to vertical gyro until 28 volts dc disappears at pitch TP-4. Measure and record ac voltage at pitch TP-10. The change between this voltage and voltage noted in step 2) should be between 50 and 90% of the voltage change noted in step 3). Disengage autopilot. Remove ground from pitch TP-6.
583
Nov 15/79 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 22-11-0 Page 529
5) Repeat steps 2) through 4) for a noseup vertical gyro tilt while monitoring 28 volts at pitch TP-3. Observe total voltage change between step 2) and 3) is 2.2 (+ 0.6) volts ac.
6) Set 3 units of trim on stabilizer trim wheel and ensure that stabilizer trim three-phase ac circuit breaker is open.
7) Move control column through neutral several times; engage autopilot, and ground pitch TP-6.
8) Observe voltage at pitch TP-10 is 1.75 (+1.0/-0.5) volts ac and record.
9) Ground pitch TP-15. Observe voltage at pitch TP-10 decreases to 0.0 (+ 0.5) volts ac.
10) Disengage autopilot and remove grounds from pitch TP-6 and TP-15.
11) Move column back and forth through neutral several times, engage autopilot, and ground pitch TP-6 and TP-12. Observe and record ac voltage at pitch TP-
10.
12) Engage HDG SEL and slowly move heading selector knob for increasing heading until 28 volts dc appears at pitch TP-4. Observe voltage change at pitch TP-10 from value recorded in 11) is 0.7 (+ 0.2) volts ac.
13) Slowly move heading selector knob toward airplane heading, and record voltage at pitch TP-10 when voltage at pitch TP-4 nulls. Observe that voltage change between this voltage and that recorded in 11) is between 50 and 90 percent of voltage in 12).
14) Return heading selector to the airplane heading. 15) Disengage autopilot, center stabilizer, close circuit breaker, remove grounds, level vertical gyro and set airspeed to 120 KIAS.
500
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址:737 AMM 飞机维护手册 AUTO FLIGHT 自动飞行 1(51)