Power Plant Flashcards
Flight idle?
Flight idle refers to the N2 idle setting used when: Associated thrust lever is at idle Landing gear is up Flaps set to 20º or less Flight idle rpm increases with altitude.
Reverse idle?
Reverse idle increases the N2 core RPM to permit acceleration to full reverse thrust in minimum time..
Approach idle
Approach idle is the N2 core speed that permits the engine to accelerate to go- around thrust in the minimum time
Approach idle is set when?
Approach idle is activated when: Thrust lever is at idle and; Approach bit is set (gear down or flaps > 20 degrees.)
Landing idle?
The purpose of landing idle is to keep the N2
elevated until reverser deployment is commanded. This
allows the engine to achieve reverse idle in an acceptable
time.
FADEC maintains landing idle for 5 seconds, and if the
thrust reversers are not activated then at the end of the 5
second period FADEC sets ground idle
Landing idle is the N2 rpm scheduled at touchdown with:
weight-on-wheels, or wheel rotation.
Reverse idle continued
Reverse idle is activated when all the following occur: At weight-on-wheels or wheel rotation Applicable reverse lever is raised Applicable thrust reverser cowl is not stowed.
Engines have to be at idle for at least how long, prior to advancing throttles for takeoff, after landing before shutting down?
2 minutes
Fuel/Oil Heat Exchanger and Fuel Filter &
Fuel Metering Unit (FMU)
Used to warm engine fuel and cool engine oil
Filter used to remove solid contaminants, depicted on FUEL
synoptic page
&
Electro-hydraulic device
Meters and distributes the fuel needed for combustion
based on signals from the FADEC system
Is not mechanically connected to the thrust lever
All thrust lever commands are electrical
Fuel System Operation:
main ejectors or DC powered boost pumps deliver fuel from collector tanks via fuel feed manifolds to engines.
FADEC? Full authority digital engine control
Control the operation and performance of the engine
through three subsystems:
Fuel control
Compressor airflow
management
Engine starting/ignition
control
System faults are indicated by
caution and status messages:
L(R) FADEC caution message L(R) FADEC FAULT 1 status message L(R) FADEC FAULT 2 status message
Aircraft dispatch with a
FAD C fault is covered by ?
MEL
FADEC can synchronize the fan or core speed of the engines with thrust levers in the?
Cruise range
N1 sync
FADEC matches the fan speed of the right engine to the left engine Disabled if the right engine N1 is not within 1.5% of left engine for at least one FADEC update
Left engine is always the master
Normally N1
SYNC is selected
N2 sync
FADEC matches core speed of right engine to the left engine Disabled if the right engine N2 is not within 2.5% of left engine for at least one FADEC update
Left engine is always the master
Normally N1
SYNC is selected
Ignition systems
Two independently controlled AC ignition systems provided for
each engine.
Controlled by FADEC
Can be manually activated
Ignition A powered by AC ESSENTIAL bus
Ignition B powered by battery bus through static inverter
Continuous ignition must be manually selected during which conditions?
Takeoff and landings on contaminated runways
Flight through moderate or heavy rain
Flight through moderate or heavy turbulence
Flight in vicinity of thunderstorms
ATS DOES WHAT.?
ATS converts pneumatic energy to mechanical motion.
Mounted on the accessory gearbox.
When start switchlight is pressed in?
Isolation valve opens
Start valve on associated engine opens
White START switchlight illuminates
L or R ENGINE START status message displayed
Stop switch/light:
Will discontinue the start sequence by closing the ATS valve on
associated engine
Bleed air leak detection
Dual loop system
• Divided into 5 zones and each can be isolated by
means of a shut-off valve
• If leak detected, no automatic valve shut-off
• Indicated by EICAS message and/or switch/light
Systems influenced by thrust lever positions?
Landing gear warning Takeoff configuration warning Cabin pressure Ground lift device SSCU
GA is calculated by FADEC
when:
Approach bit is set: flaps > 20º or landing gear down (thrust lever in the cruise range) When thrust lever placed in TOGA detent (anytime after takeoff)
If uncommanded
deployment of the thrust
reverser occurs, FADEC
commands:
The FADEC commands the reverser to close
Sets idle rpm on the affected engine.
