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Flashcards in Powerplant Deck (34)
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1
Q

What is the in-flight start envelope display.

A

It is a table of the current altitude and the two lower, in 2000’ increments, and airspeeds that will result in the appropriate windmilling RPM for a windmilling air-start. Displayed when the respective FIRE SWITCH is in, AND

  1. The Fuel Control Switch is in CUTOFF.
  2. N2 RPM is below IDLE.
  3. The Primary and Secondary EICAS is displayed.
2
Q

What are the engines on the 767 and what is their rated thrust?

A

GE CF6-80C2B6F - Rated at 60,200#.
(MW - CF6-80A - Rated at 46,900#)
(763F GE CF6-80C2B7F - Rated at 62,100#)

3
Q

What does a Magenta “X-BLEED” indication mean, and where would it be, and why would it be there?

A
  • Indicates that a X-Bleed Start is recommended due to lower than optimal N2 RPM (Marked with a Magenta Bug).
  • It is on the N2 Analog Dial on the Secondary EICAS Display, and is the MIN N2 RPM at which fuel should be introduced.
4
Q

How is Low Engine Oil Pressure indicated?

A

On the Forward Center Panel, the are Amber L and R ENG OIL PRESS Annunciator Lights. They can also indicate an oil pressure switch malfunction.

5
Q

What is the minimum oil quantity?

A

17 Quarts.

6
Q

What are the different sources of Vibration, and how are they displayed?

A

There are four different indications for Vibration on the Secondary EICAS Display - FAN (low press comp) LPT (low press turbine) N2 (high pressure comp) and BB (broad band) - only the highest of which is displayed.

7
Q

Describe the Engines.

A
  • CF6-80C2B6F
  • 60,200#
  • Two-rotor axial flow turbo fans
  • High compression and bypass ratio
  • N1 consists of the fan and a low compressor turbine.
  • N2 consists of the high pressor compressor and turbine.
  • N2 drives the engine accessory gearbox.
  • Thrust controlled by flight deck levers, and the pilot, manually or though the autothrottles and FMC.
  • The EECs (Engine Electronic Controllers) monitor engine operation and automatically control the requested parameters.
  • Engine Indication and Crew Alerting System (EICAS)
8
Q

How long is the EGT indication inhibited from color changes?

A
  • During takeoff or go-around, the EGT indication is inhibited from changing to Amber for 5 minutes, or 10 minutes during single engine operations.
  • Red line limits are not inhibited.
9
Q

When are all engine indication displayed in Compact Display Format?

A
  • Primary (normal) and Secondary (digital only) Engine Parameters are displayed in Compact Format whenever a CRT fails.
10
Q

What does max N1 represent?

A
  • Max N1 is the maximum certified thrust for any give phase of flight and existing ambient conditions.
  • Acquired from the EEC or TMC.
  • When the EEC is working NORMally, the Thrust Levers can be placed at the forward stop without exceeding N1.
  • 117.5%
11
Q

What does the Thrust Management Computer do?

A
  • The TMC calculates a reference N1 based on PA and Temp data from the ADS for TO (1&2), D-TO, CLB (1&2) CRZ, and GA modes.
  • Modes are selected on the TMSP (Thrust Mode Select Panel) by preselecting certain functions and pressing desired mode.
  • The Assumed TEMP SEL knob rotates to select the assumed temperature on EICAS.
  • Assumed temp can also be entered into the CDU TAKEOFF REF page.
  • The TMC takes input from the ADC, IRS, TMSP, FMS, and MCP to calculate Reference N1 and Thrust Setting.
12
Q

How is Reduced Takeoff Thrust managed?

A
  • Selecting 1 or 2 on the Thrust Mode Select Panel reduces thrust to 90% and 80% respectively.
  • Assumed Temperature reduced thrust can be used in conjunction to further adjust thrust ratings.
13
Q

Describe the Assumed Temperature Takeoff Method.

A
  • The FMC can be forced to assume the temperature is different than actual by TMSP or FMC inputs.
  • If the assumed temp exceed ambient, then a D-TO and Reduced Thrust Settings occur.
  • Takeoff thrust is limited to a 25% reduction of takeoff or climb thrust, whichever is the greater thrust value.
  • Further rotation of the TMSP Temperature Select Knob or CDU TAKEOFF REF inputs do not change EICAS D-TO Assumed Takeoff Temperature indication.
14
Q

When does Reduced Climb Thrust Mode Change?

A
  • When Selected to change.
  • Automatically, when climbing through 10 and 12,000’, at which point it will have completely transitioned to CLMB P Thrust. The annunciation will disappear by 12,500.’
15
Q

Describe the EEC.

A
  • The Engine Electronic Control has full authority over engine operation.
  • Two Modes - normal and alternate - to control the engine in reference to N1.
  • Always Provides N1 Overspeed Protection, but only supplies overboost protection in Normal.
16
Q

Describe EEC Normal Mode.

A
  • The EEC uses Manual Crew or autothrottle thrust commands to set thrust, in reference to a continuously recomputed Max N1, representative of Max Thrust.
  • In EEC Normal Mode Max Thrust / Max N1 will be attained at the full forward throttle lever position.
  • L/R ENG CONTROL(s) EICAS message indicates engine control system fault.
17
Q

Describe EEC Alternate Mode.

A
  • EEC automatically uses alternate mode if the required signals are not available (ADC Signals and IRS).
  • N1 Thrust is now a function of Thrust Control Lever position.
  • Two levels of EEC Alternate Mode - soft and hard.
18
Q

Describe Soft Level EEC Alternate Mode.

A
  • Automatic Mode when EEC initially changes to Alternate Mode, and EEC switches are still in the NORM position.
  • Indicated by L/R ENG EEC MODE EICAS msg.
  • A fixed Thrust Lever Position does not change N1.
19
Q

Describe the Hard Level EEC Alternate Mode.

A
  • After automatic alternate mode reversion AND Mode Select Switches are BOTH in Alternate Mode.
  • Eliminates thrust lever stagger at equal thrust settings and asymmetric thrust may occur when levers are together.
  • Thrust protection not provided; and max thrust may be achieved at Thrust Lever angles less than full forward. (L/R ENG LIM PROT EICAS message when EPR reached/approached)
  • N1 and N2 red line protection still available.
20
Q

Describe EEC Overspeed Protection.

A
  • The EEC will limit fuel flow if N1 or N2 approaches Max RPM.
  • L/R ENG RPM LIM EICAS mess if N1 or N2 is at the limit.
  • The EEC does not provide EGT overtemp protection.
21
Q

Idle Selection

A
  • Two: min and approach
  • MIN Idle is for all phases of flight, except approach and landing.
  • Approach Idle is automatically selected when required for proper system function.
  • Engine Start Selector on CONT manually selects approach idle, as does Engine Anit-Ice and FLPS in 25 or 30.
22
Q

What are the two Idle Selection Faults?

A
  • L/R ENG LOW IDLE - indicates and engine has failed to do to approach idle.
  • IDLE DISAGREE - engines at different idle settings.
23
Q

Describe the Engine Start.

A
  • Push in and Rotate Engine Start Selector to GND. This opens the Start Valve, Engages the Air Driven Starter to N2 Rotor, and Closes the Engine Bleed Air Valve.
    (- The VALVE Light will illuminate momentarily for a second or two. You don’t want to see VALVE Light Illuminate, and L/R ENG STARTER EICAS message.)
  • Bleed Air Duct Pressure will bump up; 21% min.
  • Some N1, Some Oil Press.
  • As N2 accelerates to MAX RPM (~28%) or 30 Seconds with Min 20% N2, position Fuel Control Switch to RUN. This opens the spar and engine fuel valves, and activates the selected ignition. (Verify Spar Valve “In transit Light” )
  • 25 Seconds for light off (realistically 5 seconds)
  • EGT
24
Q

What does a magenta N1 carrot mean?

A

Thrust is controlled by the FMS and you’re also in VNAV.

25
Q

What does the VALVE Light on the ENG START Panel indicate?

A
  • Illuminated (amber): valve is not in commanded position

- N2 Rpm exceeds 50% and Starter Valve is OPEN.

26
Q

What does the NORM light on the ELEC ENG CONTROL Panel indicate?

A
  • NORM Illuminated - EEC trims FF to limit N1.
  • NORM Illuminated (ALTN Illuminated) - (Soft) Alternate Mode Active
  • NORM Not Illuminated (ALTN illuminated/Selected) - (Hard) Alternate Mode Active
27
Q

What happens in the event of a complete EEC failure?

A
  • “Sub Idle Condition”
28
Q

How are the EECs powered?

A

Each has its own dedicated AC GEN, in the Engine Accessory Gearbox, driven by the N2 rotor.

29
Q

Schematically, Where is the EEC?

A

It is soft mounted to the Fuel Metering Unit.

30
Q

Describe the flow of fuel from the tank to the engine?

A
  • Fuel pumps in the tanks.
  • Through a spar valve in the main tank.
  • Pressure added by First and Second Stage Fuel Pumps.
  • Fuel / Oil heater preheats fuel.
  • Passes through a fuel filter.
  • Controlled (by FMU and EEC) to meet thrust requirements.
  • Passes through the Engine Fuel Valve and
  • Fuel Flow Meters Measure FF.
31
Q

Starter Duty Cycle

A
  • Normal - 1 Min ON, 1 Minute OFF

- Extended - Up to 5 Min On, then OFF for ..

32
Q

Describe the Thrust Reversers.

A
  • Pneumatically actuated.
  • EEC controlled.
  • Amber REV above N1 Box = In Transit
  • Green REV above N1 Box = Fully Deployed
  • At Aft detent, A/T Disengaged, and Speed Brakes Deployed.
  • REV ISLN light just above Fuel Control Panel and below Thrust Quadrant = Fault Detected in REV System. Only shows on ground.
33
Q

When does the STBY ENG Indicator automatically display?

What does it show?

A
  • Both EICAS Displays Fail, or Both Main AC Buses fail.

- Shows N1, EGT, and N2 Digital levels, and their associated limits.

34
Q

Describe the Engine and Spar Valve operations.

A
  • Open when the Engine Fire Switch is IN, and the Fuel Control Switch is in RUN.
  • Both close if EITHER the Engine Fire Switch is OUT, or the Fuel Control Switch in OUT.
  • if the valve position does not agree with the Fire Switch and FCS, the respective FUEL SPAR VAL or ENG FUEL VAL light will illuminate.