THRUST

THRUST REVERSER INDICATION

  • Indicates the thrust reverser position.

  • Green – fully deployed, Amber – in transition , Red – discrepancy between selected and actual reverser position.


N1 INDICATION

  • Displays the percentage of N1 rpm.

  • Green – normal operating range, Red – Operating limit exceeded, Amber dashed – invalid information or value out of displayable range.


N1 WING ANTI-ICE CYAN LINE

  • Displayed only in icing conditions during final approach when configured for landing.

  • Indicates the minimum thrust level (N1 value) to meet bleed requirements.


N1 TARGET INDICATION (DIGITAL READOUT AND BUG)

  • Maximum N1 for the engine thrust rating mode indicated on EICAS.

THRUST RATING MODE INDICATION

  • Indicates the current thrust-rating mode.


ENGINE THRUST RATINGS

  • FADEC calculates the maximum N1 for each thrust rate mode.

  • Available thrust modes: Takeoff, Takeoff Reserve, Go-Around, Go-Around Reserve, Maximum Continuous Thrust, Maximum Climb, Maximum Cruise, and Idle:

    • Takeoff (TO-x)

      • Thrust used for a normal takeoff.

    • Maximum Takeoff Reserve

      • Whenever ATTCS is triggered, TO-x RSV automatically becomes the maximum N1, as long as the thrust levers are set to TO/GA.

    • Go-Around (GA)

      • Activated in flight whenever the landing gear and flaps are down. GA mode can also be set from CRZ, CON, or CLB by pressing TOGA.

    • Go-Around Reserve (GA-RSV)

      • Highest engine thrust possible.

    • Maximum Continuous Rating (CON)

      • Used in emergency situations where thrust higher than usual is required.

    • Maximum Climb Rating (CLB-1, CLB-2)

      • Whenever the selected takeoff thrust is lower than CLB-1 the CLB-2 modes becomes the default.

      • Manual switching between the climb modes is possible in flight on the MCDU-TRS page.

    • Maximum Cruise Rating (CRZ)

      • Maximum N1 that can be used for a normal cruise flight.

      • Automatically selected when level at the altitude set on the altitude pre-selector for 90 seconds and airspeed is within 5kts from the pre-selected airspeed.

    • IDLE

      • IDLE modes are automatically adjusted by the FADEC in order to maintain the minimum thrust necessary to provide the required bleed pressure to the airplane.

      • Whenever ICE CONDITION is sensed the N1 for the FLIGHT IDLE and APPROACH IDLE is automatically increased to maintain the minimum bleed pressure required for the ANTI ICE system operation.

ATTCS INDICATION

  • Displayed to indicate the Automatic Takeoff Thrust Control System status.

  • Green – engaged (only when TL reach TO/GA position), White – armed, Blank – not selected.


ASSUMED TEMPERATURE INDICATION

  • Displays the FLEX assumed temperature set in the MCDU TRS page.


AUTOMATIC TAKEOFF THRUST CONTROL SYSTEM (ATTCS)

  • Controlled by the FADEC and is available on takeoff and go-around.

  • Selection is made in the MCDU – TAKEOFF DATASET MENU page.

  • Takeoff with ATTCS OFF is prohibited.

  • Provides maximum thrust reserve (RSV) according to current rate previously selected via the MCDU on the T/O Dataset page.

  • ATTCS automatically commands RSV whenever it is engaged, thrust levers are at TOGA, and one of the following:

    • N1 difference > 15% between engines.

    • Engine failure during takeoff or go-around.

    • Windshear detection.

  • Moving the thrust levers to the MAX position with ATTCS armed commands RSV power.


FLEXIBLE TAKEOFF

  • A reduced takeoff thrust based on an assumed temperature.

  • An assumed higher temperature makes the engine think it will overtempt so it reduces the thrust.

  • Maximum allowable flex reduction is 25%.

  • If the FLEX temperature is changed to a higher FLEX temperature the N1 target will decrease.

  • Not allowed when windshear advisories are in effect.


N1 REQUEST INDICATION

  • Indicates the momentary difference (transient) between actual N1 and requested N1 applied by TLA.


MAXIMUM N1 INDICATION

  • Indicates the maximum allowable N1 (maximum thrust) for the current thrust rating and operating conditions. If thrust lever is set to MAX, the N1 request value will be equal to the Maximum N1 value.


N1 RED LINE

  • Indicates the N1 limit.


INTERTURBINE TEMPERATURE (ITT) INDICATION

  • Green – normal operating range, Red – operating limit exceeded.

  • Indicates engine fire condition.


ITT RED/AMBER LINE

  • Maximum allowable ITT for the current flight phase.

  • Limits thrust, thereby avoiding the maximum allowable ITT to be exceeded.

Currently the ITT red/amber lines are static.


IGNITION CHANNEL INDICATION

  • Indicates the enabled ignition channel.

  • A WML icon is displayed whenever the FADEC has detected an engine flameout and the auto re-light system is actuating to restart the engine.


N2 INDICATION

  • Displays the percentage of N2 rpm.

  • Green – normal operating range, Red – operating limit exceeded.


OVERSPEED PROTECTION

  • In the event of 3 consecutive overspeed detections within 30 seconds FADEC will not relight the engine.

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