CH7 ENGINES, APU Flashcards
What primary engine indications are displayed full time on the EICAS display?
N1, EGT
What does TAT stand for and how is it displayed on the EICAS?
Total Air Temperature (TAT) is displayed in white and measured in degrees Celsius (°C).
What does the green display on the EICAS indicate?
Selected FMS thrust reference mode
What does the displayed thrust reference mode ‘TO’ indicate?
Maximum rated takeoff thrust
This is one of the thrust reference modes available.
What is the thrust reference mode ‘D-TO’ used for?
Assumed temperature derated takeoff thrust
This mode allows for reduced thrust during takeoff based on assumed temperature.
List the derated takeoff thrust modes available.
- TO 1 - derate one takeoff thrust
- TO 2 - derate two takeoff thrust
- D-TO 1 - derate one assumed temperature derated takeoff thrust
- D-TO 2 - derate two assumed temperature derated takeoff thrust
What does the ‘CLB’ thrust reference mode represent?
Maximum rated climb thrust
What is indicated when the thrust reverser is displayed as REV (amber)?
Reverser in transit
This indicates that the thrust reverser is moving to its deployed position.
What does a displayed REV (green) indicate?
Reverser fully deployed
This indicates that the thrust reverser is in the fully deployed position, allowing for reverse thrust.
What is the purpose of the ‘Assumed Temperature’ indication?
Selected assumed temperature (°C) for reduced thrust takeoff
This helps in optimizing performance during takeoff.
What does the thrust reference mode ‘CON’ stand for?
Maximum rated continuous thrust
What is the thrust reference mode ‘G/A’ used for?
Maximum go-around thrust
Fill in the blank: The thrust reference mode ‘CRZ’ indicates _______.
Maximum rated cruise thrust
What happens to N1 indications when reverse thrust is activated?
The following indications are not displayed:
* maximum N1 line
* commanded N1
* reference/target N1 indication
* reference N1
What does the N1 Red Line displayed in EICAS represent?
N1 RPM operating limit
What does the Reference/Target N1 indicate when displayed in green?
Reference N1 limit
What does displayed (magenta) target N1 represent when VNAV is active?
Target FMC commanded N1 when autothrottle is connected in THR or THR REF mode, or autothrottle disconnected
What does displayed (white) commanded N1 signify?
Commanded N1
What does a white commanded N1 sector indicate?
Momentary difference between engine N1 and N1 commanded by thrust lever position
What does an amber filled commanded N1 sector indicate?
A difference between engine N1 and commanded N1 exists and engine N1 is not closing toward commanded N1. EICAS alert message ENG THRUST (L or R) is displayed
What does displayed (amber) maximum N1 line represent?
Maximum N1
What does displayed (digital, green) reference N1 indicate?
Reference N1
What does digital N1 RPM (%) displayed in white indicate?
Normal operating range
What does digital N1 RPM (%) displayed in red signify?
Operating limit reached
What does a red N1 indication signify?
Operating limit reached
What does a green Ice Crystal Anti-Ice Indication (ICA) indicate?
Ice crystal anti-ice function is on
Ice crystal icing conditions may not be present
True or False: Each engine’s ice crystal icing function is dependent on the other.
False
What does the red EGT indication represent?
Maximum takeoff EGT limit
What does the amber EGT band indicate?
Maximum continuous EGT limit
What does a white EGT indication signify?
Normal operating range
What does an amber EGT indication signify?
Maximum continuous limit reached
What does a red EGT indication signify?
Maximum start or takeoff limit reached
Under what conditions is the EGT Start Limit Line displayed in red?
When the engine fire switch is in and:
* The FUEL CONTROL switch is in CUTOFF
* The N2 RPM is below idle
What temperature unit is used for EGT?
Degrees Celsius (°C)
What is indicated by the EGT when it is displayed in white?
Normal operating range
What is indicated by the EGT when it is displayed in amber?
Maximum continuous limit reached
What is indicated by the EGT when it is displayed in red?
Maximum start or takeoff limit reached
Fill in the blank: The EGT Start Limit Line is displayed in _______ when specific conditions are met.
red
What are the two conditions that can cause the EGT Start Limit Line to display red?
- FUEL CONTROL switch is in CUTOFF
- N2 RPM is below idle
What does the In-Flight Start Envelope indicate?
MAGENTA
Airspeed range necessary for an in-flight start at the current flight level or maximum flight level when the respective engine fire switch is in
This is relevant when the FUEL CONTROL switch is in CUTOFF or the engine N2 RPM is below idle.
When is the X-START indication displayed?
Displayed (magenta) when current altitude and/or airspeed are outside the windmilling start envelope
Starter assist is recommended for an in-flight start in this case.
What are the conditions for the In-Flight Start Envelope to be displayed?
When the respective engine fire switch is in and either the FUEL CONTROL switch is in CUTOFF or the engine N2 RPM is below idle
This is crucial for determining the feasibility of an in-flight start.
True or False: The In-Flight Start Envelope is displayed in white.
False
The In-Flight Start Envelope is displayed in magenta.
What does the Secondary Engine Display show?
• N2 RPM
• fuel flow (FF)
• oil pressure
• oil temperature
• oil quantity
• vibration
What does the N2 RPM indicate when displayed in white?
Normal operating range
What does the N2 RPM indicate when displayed in red?
Operating limit reached
What does the N2 Red Line indicate?
N2 RPM operating limit
The red line displayed indicates the maximum RPM that should not be exceeded.
What color indicates the normal operating range for N2 RPM?
White
White indicates that the N2 RPM is within the normal operating range.
What happens when the N2 RPM reaches its operating limit?
It is displayed in red
The red display signals that the engine has reached its maximum RPM limit.
What does the RUNNING indication displayed in green signify?
Fuel control switch is in RUN position and engine is at or above idle
The green RUNNING indication shows that the engine is functioning correctly.
When does the RUNNING indication blank?
30 seconds after the engine reaches idle
This indicates that the engine has stabilized at idle and is no longer in the starting phase.
What does the AUTOSTART indication signify?
EEC is in autostart mode
The AUTOSTART indication blanks when the system is no longer attempting an engine start.
What does the AUTORELIGHT indication signify?
EEC is in auto-relight mode
The AUTORELIGHT indication blanks when the system is no longer attempting an engine relight.
What does the Idle Target Indication indicate?
Approximate RPM where the engine can maintain self-sustained running operation.
Under what conditions is the Idle Target Indication displayed in green?
When the fuel control switch is in the RUN position and the engine is below idle.
What does the Fuel Flow Indication display?
Fuel flow to the engine in kilograms per hour x 1000.
What color is the Fuel Flow Indication?
White.
What does a white oil pressure indication signify?
Normal operating range
What does an amber oil pressure indication signify?
Caution range reached
What does a red oil pressure indication signify?
Operating limit reached
When is the oil pressure caution range displayed in amber?
Only on the ground below 80 knots
How is engine oil pressure displayed?
With a pointer indicating normal, caution, or limit ranges
What changes about the oil pressure red line?
Its vertical position varies with N2 RPM
What does the red line indicate on the EICAS display for oil temperature?
Oil temperature operating limit
What does the white color indicate for engine oil temperature on the display?
Normal operating range
What does the amber color signify in the oil temperature indications?
Caution range reached
What does the red color signify for oil temperature on the display?
Operating limit reached
What does the oil temperature pointer display when in the caution range?
Amber
What is indicated when the oil quantity shows ‘LO’?
Low oil quantity
What temperature indication color represents the normal operating range?
White
What does EICAS Display indicate in terms of oil quantity?
Usable oil quantity (liters)
What does it mean when oil quantity is displayed in black numbers on a white background?
Low quantity
This indicates that the oil quantity is below the normal operating range.
What does the LO indication mean on the EICAS Display?
Displayed (white) when quantity is low
This alerts the crew to a low oil condition.
What does the Engine Vibration Indication display?
Engine vibration
This is critical for monitoring engine health.
What color indicates normal operating range for engine vibration?
(white) - normal operating range
What does black numbers on a white background indicate in the context of engine vibration?
High vibration
This indicates that the engine is experiencing excessive vibration, which may require immediate attention.
Fill in the blank: Usable oil quantity is displayed in _______ color when it is low.
black numbers on a white background
What does the vibration source indicator display?
Identifies the vibration source being displayed, with the highest vibration source shown in white.
The sources include N1 rotor vibration, N2 rotor vibration, and BB (broad band) vibration.
What is indicated when BB (broad band) vibration is displayed?
The source is unknown and average vibration is displayed.
What does the Engine Vibration Pointer indicate?
Indicates engine vibration level displayed in white.
What is the Engine Vibration High Band?
The vibration level at which automatic display of secondary engine indications occurs, displayed in white.
Fill in the blank: The vibration source with the highest vibration is displayed in _______.
[white].
What do the reverse thrust levers control?
Engine reverse thrust
Reverse thrust can only be selected when the forward thrust levers are closed.
What happens when reverse thrust levers are selected?
Actuates the automatic speedbrakes
What do the forward thrust levers control?
Engine forward thrust
The thrust levers can only be advanced if the reverse thrust levers are down.
What does the RUN position of the FUEL CONTROL Switch do?
Opens the spar fuel valve, arms the engine fuel valve, arms the selected igniters
The EEC opens the fuel valve and turns on the igniters when required.
What happens when the FUEL CONTROL Switch is in the CUTOFF position?
Closes the engine fuel valve, removes igniter power, unlocks the engine fire switch
The spar fuel valve also closes if the start switch is not in START.
What are the functions of the engine fuel valve when the FUEL CONTROL Switch is in RUN?
Opens the valve and arms the engine fuel valve
The EEC controls the opening of the valve when necessary.
What does the FUEL CONTROL Switch do when it is in CUTOFF?
Closes the engine fuel valve and removes igniter power
It also unlocks the engine fire switch.
What does the NORM setting on the Electronic Engine Control (EEC) Mode Switch do?
Selects the normal engine control mode for engine control. The EEC sets thrust using N1 as the controlling parameter.
What happens when the EEC Mode Switch is set to Off?
Selects the alternate engine control mode for engine control. Thrust is set using N1 RPM as the controlling parameter.
What does an illuminated (amber) Electronic Engine Control (EEC) Alternate (ALTN) Light indicate?
The alternate engine control mode is either automatically or manually selected.
What is the function of the START Selector in engine controls?
Initiates engine start by commanding the fuel spar valve to open and the starter motors to energize. Releases to NORM at completion of start.
What occurs when the START Selector is set to NORM?
The starter motor is de-energized.
What is the function of the APU Selector in the OFF position?
Initiates normal shutdown and resets auto shutdown fault logic
What happens when the APU Selector is in the ON position?
Opens the APU fuel spar valve and inlet door, activates AC or DC fuel pump, powers the APU controller
What is the purpose of the START position on the APU Selector?
Initiates automatic start sequence
The START position is momentary and spring-loaded to return to ON.
True or False: The APU controller will always start immediately when the START position is selected.
False
If the common core system is not running, the APU controller delays start until the required common core applications are available.
What does an illuminated APU FAULT Light indicate?
APU fault and/or fire is detected, APU shutdown due to fault and/or fire, momentarily during APU controller self-test
What type of engines power the airplane?
Two General Electric GEnx-1B76A engines
What is the takeoff thrust rating for each GEnx-1B76A engine?
76,100 pounds
What does BET stand for and why is it useful?
Boeing Equivalent Thrust; useful as a takeoff reference under certain conditions
What type of engine is the GEnx-1B76A?
Two rotor axial flow turbofan engine of high compression and bypass ratio
What components make up the N1 rotor?
Fan, low pressure compressor section, low pressure turbine section
What does the N2 rotor consist of?
High pressure compressor section and high pressure turbine section
Are the N1 and N2 rotors mechanically dependent or independent?
Mechanically independent
What drives the engine accessory gearbox?
High speed N2 engine shaft
How is each engine controlled?
By an EEC (Electronic Engine Control)
What does the EEC monitor?
Autothrottle and flight crew inputs through the thrust levers
How can thrust be set in the engines?
Automatically by the autothrottle system or manually by the flight crew
How are both engines set to operate in terms of thrust?
At the same thrust rating
What might the EGT amber band indicate?
Maximum continuous limit difference between engines
What happens if engine data is not available?
The associated engine indication blanks
There is no EICAS message relating to the loss of engine data.
How can secondary engine indications be displayed?
By pushing either secondary engine display switch (ENG on the display select panel)
Secondary engine indications are automatically displayed under certain conditions.
When are secondary engine indications automatically displayed on EICAS?
- Displays initially receive electrical power
- FUEL CONTROL switch is moved to CUTOFF in flight
- Engine fire switch is pulled in flight
- Secondary engine parameter is exceeded
- Engine N2 RPM is below idle in flight
- Start selector is in the START position
- FUEL FLOW ENG L/R Advisory is shown
When these conditions occur, secondary engine parameters cannot be cleared until the condition is no longer present.
True or False: Secondary engine parameters can be cleared immediately after they are displayed.
False
They can only be cleared after the condition causing their display is resolved.
What action is needed to clear secondary engine parameters after the condition is resolved?
Push the engine (ENG) display switch
This action is necessary after the condition that caused the display is no longer present.
What are the two types of indications for primary engine and N2 indications?
Digital readouts and round dial/moving pointer indications
What do the digital readouts for oil pressure, oil temperature, and vibration indications consist of?
Digital readouts and vertical indication/moving pointers
How is the normal operating range displayed on the dial or vertical indication?
In white
What color indicates caution ranges for oil temperature and oil pressure vertical indications?
Amber
What happens to the digital readout and pointer when oil temperature reaches the caution range?
They change color to amber
What color do indications change to when they reach operating limits indicated by red lines?
Red
What happens to the box enclosing the digital readout if an N1, N2, or EGT red line is exceeded?
It remains red after the exceeded limit returns to the normal range
What is the maximum continuous limit for EGT represented by?
An amber band
When is the EGT indication inhibited from changing to amber during takeoff or go-around?
For five minutes
What is displayed for low oil quantity on the digital readout?
Black text on a white background with LO displayed adjacent
What indicates high engine vibration on the digital readout?
Black text on a white background
What does EEC stand for?
Electronic Engine Control
What does the EEC use to control engine operation?
Thrust lever inputs