Flashcards in Engines Deck (44)
What type of engines does the 737NG have? Rated thrust?
2x CFM56-7 engines.
27,300 pounds depending.
What is the N1 rotor consisted of?
Fan, low pressure compressor and low pressure turbine.
What is the N2 rotor consisted of?
High pressure compressor and high pressure turbine. All engine gearboxes are powered off the N2 rotor including accessory gearbox and a bleed air starter drives the N2 rotor for engine start.
How many ignitor plugs per engine?
2 congrolled through the IGN switch.
T/F: The dual channel EECs ensure reliablity through automatic transfer in the event of a _______.
single channel failure.
What are the two modes for the EECs?
Normal or Alternate (alternate has hard and soft mode).
T/F: Max thrust is always available at the forward stop
____ and ____ overspeed protection is provided by the EECs in both normal and alternate mode.
T/F: The EECs provide EGT exceedance protection in normal.
How do you get to alternate mode in the EEC?
EEC automatically goes to soft alternate when signals for normal are lost. This will be indicated by both the ON and ALTN lights in EEC switch.
Going from Normal to Soft Alternate shouldn't have any immediate effect on engine thrust since this mode does what?
uses last valid flight conditions to control parameters.
How do you get to Hard Alternate for the EECs?
retarding thrust levers to idle or manually selecting ALTN via EEC switch.
For a given thrust lever position, Hard alternate will _______.
Always provide thrust equal to or greater than that provided in Normal.
What is the difference between ground min idle and flight min idle?
ground: selected during taxi out and after touchdown
flight: selected in flight unless approach idle is active.
How is approach idle selected?
flaps are in landing configuration or anytime engine anti-ice is selected ON for either engine. Approach idle allows for better engine acceleration in event of go around.
An AC power source is generally preferred but the engine can be started using ______only
What are the power sources for IGN L and IGN R?
IGN L: associated AC XFR BUS
IGN R: AC STBY BUS.
Which ignition must be used for a battery start?
How do the EECs provide auto-relight capability?
In event of flameout both ignites are activated automatically when N2 RPM is below idle or a rapid uncommanded decrease in N2 RPM occurs.
What does a magenta X-BLD mean?
ambient flight conditions require a crossbled start.
______and _______ engine starts are available in flight however the abnormal start protections _________.
Windmill; crossbled; are not available.
The _____ meters fuel through the ______ to control required engine thrust.
EEC; HMU (hydro-mechanical Unit)
How many engine fuel pumps are there?
2; 1st stage is after spar fuel shutoff valve; 2nd is after fuel filter and goes to HMU.
SPAR VALVE CLOSED and ENG VALVE CLOSED (blue ) indicate what?
position of the valves.
Where is the fuel flow readings taken from?
just after the Engine Shutoff valve
Oil from the engine driven oil pump is used for what?
lubricate the engine bearings and accessory gearbox.
When does LOW OIL PRESSURE display?
oil pressure is at or below red line.
Reverser operation will be at a _________ and some thrust asymmetry can be expected when using standby hydraulic pressure.
The reverse thrust levers are mechanically restricted from operating until at _______.
IDLE. Also, reverse thrust can only be deployed when either RA is reading below 10' or ground mode is sensed through Air and Ground safety sensor.