Oil pressure and oil temperature indications are displayed with a round dial/moving pointer. Operating and caution ranges and limits are displayed with green and yellow bands and red radials. The oil quantity indicator displays a digital readout of quantity as a percentage of full.
The airborne vibration monitor indications are displayed with a round dial/moving pointer.
N1, N2, oil quantity, and engine vibration are displayed directly from the engine sensors.
Engine Indications (Airplanes with Conventional Instruments)
Engine indications are displayed on the center instrument panel. N1, EGT, N2, and
FF/FU are the primary indications and are displayed as both digital readouts and
round dial/moving pointer indications. N1, EGT, and N2 have operating and
caution ranges and limits indicated by green and yellow bands and red radials.
When the round red warning light on the indicator is illuminated it indicates the
limit for the related engine parameter has been reached or exceeded. The red
warning light remains illuminated until the engine parameter is reduced below the
limit.
Oil pressure, oil temperature, and oil quantity indications are displayed with a
round dial/moving pointer. Operating and caution ranges and limits are displayed
with green and yellow bands and red radials.
The airborne vibration monitor indications are displayed with a round dial/moving
pointer.
N1, N2, oil quantity, and engine vibration are displayed directly from the engine
sensors.
Power Management Control (PMC)
The thrust control system consists of a hydromechanical MEC unit and a PMC unit mounted on each engine. The PMC is an electronic system with limited authority over the MEC.
The PMC uses MEC power lever angle, N1 speed, and inlet temperature and pressure to adjust, or trim, the MEC to obtain the desired N1 speed. The PMC adjusts fuel flow as a function of thrust lever angle.
The PMC provides a constant thrust climb feature once the thrust lever is set as the beginning of climb. Thus, when thrust is set for the climb, the PMC automatically maintains that thrust throughout the climb profile with no further thrust lever adjustments. If the thrust lever is repositioned, the PMC maintains the setting corresponding to the new thrust lever angle.
Copyright . The Boeing Company. See title page for details.
7.20.2 August 1, 2003
Engines, APU -Engine System Description
737 Operations Manual
The PMC includes failure detection and annunciation modules which detect PMC failures and provide a signal to the crew. For detectable failure conditions, the PMC schedules a slow N1 drift over approximately 30 seconds and then illuminates the PMC INOP light, the ENG system annunciator, and the MASTER CAUTION lights. For a PMC failure, the PMC can be selected OFF by a switch on the aft overhead panel. The engine speed is then controlled by the hydromechanical MEC only. The PMC INOP Light is suppressed below starter cutout engine speed.
Idle RPM
There are two engine idle speeds, low idle and high idle.
The minimum engine speed for all flight phases is high idle, which varies with
flight conditions. As temperature and airspeed decrease, high idle speed also
decreases. The average high idle setting is approximately 32% N1.
To reduce braking activity, engine idle speed is reduced to low idle, approximately
22% N1, four seconds after touchdown. The four second delay is provided to
enhance engine speed acceleration for reverse thrust.
Minimum Engine Speed Control
On airplanes that have the autothrottles connected to the FLT position of the engine start switch circuit, in flight above 500 feet radio altitude, anytime one or both engine start switch(es) are placed to FLT, the autothrottle, if armed, maintains a minimum engine speed of 45% N1. This increases engine tolerance to water ingestion.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：737-300机组操作手册Flight Crew Operations Manual FCOM 2(61)
