(b)
A vertical alert is given at the last bottom of descent (BOD) waypoint; for pending transition from descent path mode or descent flight path angle (FPA) mode, to the speed mode.
(2)
The speed arm annunciator will flash during cruise if the descent speed mode is armed, the airplane is within 15 nautical miles of top of descent (TOD), and a clearance altitude is not selected below present cruise altitude. The annunciator will light steadily when the clearance altitude is set below cruise altitude.
D. SPEED Annunciator
(1)
The speed (SPEED) annunciator lights green when the PMS is controlling to a constant speed (MACH/CAS), in the descent speed mode or in the descent manual mode.
(2)
The speed annunciator also lights when the PMS is in the descent path mode or in the descent flight path angle (FPA) mode, and Vmin/Vmax limits are reached.
NOTE: If Vmin/Vmax limits are reached during a path descent, the
____ speed annunciator lights to indicate that in the path mode, speed control is given priority over path control. In this condition the PATH ARM annunciator will also light.
E. T/HOLD Annunciator
(1) The throttle hold (T/HOLD) annunciator lights green during a descent; when the PMS has retarded the throttles to the required power setting, and is in the 'throttle hold' mode.
13. Panel Mounted Alerts (Fig. 1)
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EFFECTIVITY
AIRPLANES WITH PMS 02 Page 28 Aug 25/83
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A. VERT ALERT Annunciator
(1) The vertical alert (VERT ALERT) annunciator begins to flash approximately 10 seconds prior to a vertical flight path change. When the vertical flight path change occurs the annunciator lights steadily for approximately 76 seconds.
B. PMS Annunciator.
(1) The performance management system (PMS) annunciator lights steadily when a PMS malfunction error code is detected. The malfunction error code is detected by the software in the PMS computer unit.
C. A/T P/RST Annunciator. (Flight Mode Annunciator Panel)
(1)
Red Warning.
(a)
In the PMS mode, the A/T P/RST annunciator flashes red if the auto throttle engage switch is placed to OFF.
(b)
In the PMS mode, the A/T P/RST annunciator illuminates steady red when the LEDEX relay, in the PMS switching unit, has failed. If this occurs, the switching unit must be replaced.
(2)
AMBER Warning
(a)
If the auto throttle engage switch is OFF when the PMS mode is selected, the A/T P/RST annunciator flashes amber.
(b)
In the PMS mode the A/T P/RST annunciator lights steadily amber for a PMS overboost condition.
NOTE: A RED Warning will override an AMBER Warning.
____
14. Engine Pressure Ratio Indicator (IB Airplanes)(Fig. 9)
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A. Four engine pressure ratio (EPR) indicators, one for each engine, are in a horizontal row on the pilot's center instrument panel. The EPR indicator provides a pointer and a digital readout of the engine exhaust pressure ratio. The indicator also provides an index and a digital readout of the command (target) EPR signal from the performance management system.
B. The EPR pointer displays the engine exhaust and inlet pressure ratio against a graduated scale. This ratio is also displayed on the EPR counter. Data signals that drive the EPR pointer and counter are produced by an engine mounted EPR transmitter.
C. The command EPR display operates in either an automatic or a manual mode. When the command or set knob is in the depressed or normal position, the command display is in the automatic mode operating with the command (target) EPR signal from the PMS. Pulling the knob out disables the automatic mode and permits the command display to be driven by rotating the command set knob.
D. In the automatic mode, a warning flag will cover the command counter, if the PMS computer EPR valid signal fails, or if the indicator fails.
E. In the manual mode, a black 'M' covers the left digit of the command counter.
15. N1 Tachometer Indicator (AF Airplanes)(Fig. 10).
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A. Four N1 tachometer indicators, one for each engine, are in a horizontal row on the pilot's center instrument panel. The indicator provides a pointer and a digital readout of the engine N1 percent RPM. The indicator also provides an index and a digital readout of the command (target) N1 signal from the performance management system.
EFFECTIVITY
AIRPLANES WITH PMS 09 Page 29 Dec 25/91
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