Operation Manual Part 2

Aerosoft – Digital Aviation
CRJ-70 & CRJ-900
AOM PART 2
Systems Description
VOL
5
5-1-119
26-Jul-2017
HIGH POWER SCHEDULE
There is no operational procedure in which the use of the high-power schedule is required.
Nevertheless, by activating the high-power schedule for an engine, the FADEC will compute and command
MCT, maximum continuous thrust, as soon as the thrust levers is in climb detent. When advanced further to
the take-off detent, APR, automatic power reserve, is activated.
N
1
AND N
2
SYNCHRONISATION
To reduce noise the CRJ offers a feature to synchronize N
1
or N
2
of both engines. In both cases the left engine
is regarded as the master engine and the right engines is slaved to the left engine.
N
1
sync means the right engine needs to be within 1.5% N
1
of the left engine.
N
2
sync means the right engine needs to be within 7,5% N
2
of the left engine.
ENGINE OVERSPEED PROTECTION
An overspeed condition exists as soon as N
2
exceeds 107%.
In case an overspeed condition is detected the fuel supply to the engine is cut off automatically and the engine
flames out. The FADEC will then detect the flameout and turn the ignition on – as soon as the overspeed
condition is cleared fuel flow is reactivated to the engine.
ENGINE N
2
INDICATIONS WHEN USING WING ANTI-ICE
Using wing-anti-ice requires sufficient supply of bleed air. At certain ambient conditions the FADEC will trigger
a signal to the N
2
indicators, to display a partial white band below the normal green band.
Maintaining N
2
in the green band will ensure sufficient bleed air supply. In case N
2
is reduced further into the
white band, air flow to the wing-anti-ice won’t suffice. The N
2
pointers and digital indications will turn white
and the L/R WING A/I caution message may be displayed.
Increase N
2
into the green range again to remove the caution message.
STARTING AND IGNITION SYSTEM