Embraer EMB145, Operation Manual

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AIRPLANE
OPERATIONS
MANUAL
POWERPLANT
REVISION 41
2-10-40
Page
5
Code
01
Copyright © by Embraer. Refer to cover page for details.
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GROUND/FLIGHT IDLE THRUST SCHEDULE
There is only one IDLE position on the thrust lever control pedestal.
However, there are two different IDLE ratings (ground and flight Idle),
set as a function of the Air/Ground input to the FADEC:
−
GROUND IDLE SPEED
During ground operations, the FADEC commands the engine to
Ground Idle Speed, which is scheduled in order to:
−
Avoid engine flameout, overtemperature or inability to accelerate.
−
Provide the required air bleed flow pressure and temperature for
the ECS.
−
Provide the required gas generator speed to drive the
accessories.
Ground Idle Speed is scheduled as a function of ambient
temperature.
−
FLIGHT IDLE THRUST
In flight operation, the FADEC will command the engine to Flight Idle
Thrust, which is scheduled in order to:
−
Avoid engine flameout, overtemperature or inability to accelerate.
−
Provide the required bleed airflow pressure and temperature for
the ECS and for the Anti-Icing System. If the FADECs receive an
indication that the anti-icing system is on, Flight Idle thrust is
rescheduled in order to provide the required air bleed flow,
pressure and temperature. This automatic A-ICE Flight Idle
rescheduling is inhibited below 15000 ft if the landing gear is down
and locked.
−
Enable the FADEC to accelerate the engine from Flight Idle
Thrust to 100% of the Go-around thrust mode in 8 seconds or
less, at or below 9500 ft.
CLOSED-LOOP FAN SPEED CONTROL
The primary control mode of the engine is closed-loop fan speed
control. The fan speed requested by thrust lever is compared to the
measured fan speed. An error signal proportional to the difference
between the request and measured fan speed is used to adjust the
commanded fuel flow to the engine to drive the fan speed error to zero.