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Power Plant
AE3007 Rolls Royce Turbofan Engine.

High bypass ratio, two-spool axial flow turbofan.

Max T/O Thrust - 7426 lbs (XR 8810lbs)
Power Plant Design Features
Single stage fan.
14 stage axial-flow compressor w/ inlet guide vanes & 5 varible-geometry stator stages.
2-stage high pressure turbine to drive the compressor.
3-stage low pressure turbine to drive the fan.
Dual redundant, FADEC.
Accessory Gearbox.
Pneumatic system for pressurization and engine starting.
Starting Sequence
Start/Stop Selector - Run 2 sec
Start/Stop Selector - Start 3 sec max

N2 rotation
14% single ignitor
Oil Pressure Rising
28% Fuel flow
w/ in 10 sec ITT rise
N1 rotation
56.4% N2 ignitor deselected
Start Complete
Check:
N1 20%
ITT 400
N2 60%
FF 300 - 400PPH
SCV close @ 53% N2
Reasons to Abort Start
Fuel flow +800 PPH prior to light up.
No light up in 10 sec after Fuel Flow Indication.
ITT rises rapidly to start limit.
ITT approaches start limit.
N2 remains steady or decreases for +30 sec.
Any unusual noise or vibration.
Engine instruments indicate abnormal conditions.
Visible burning on the exhaust pipe.
Oil pressure doesn't reach 34 psi when engine reaches stabalized idle.
Pneumatic Starting
Sending compressed air through the air turbine starter(ATS). Sources: APU(primary) Ground Cart Crossbleed from other Engine Windmilling
Engine Bleed Valve Logic
Bleed Air Button OPEN: Respective Ess. Bus energized. No massive leakage. Respective N2 +56%. Respective Fire Extinguishing Handle not pulled. Bleed is requested by one bleed consuming system.
When does 14th Stage Bleed Valve open?
9th stage pressure low( low thrust).
Anti-Ice is required.
Cross Bleed starting.
Crossbleed Starting
XBLEED_AUTO or OPEN ENG BLEED(non operating)_CLOSE ENG BLEED(operating)_OPEN N2 Operating ENG_+80% N2
What Bleed Valve assist in Engine Start?
Compressor Acceleration Bleed Valve(CABV)
When does the Starter Control Valve(SCV) Shutoff?
@ 53%N2 begins to close, should be closed @ 56.4%. EICAS msg +53%N2 plus 10 sec if not closed
How many Start attempts may you do?
Only Two then call Maintenance. Dry Motor between each start attempt. Abnormal Engine Start checklist every time.
Vapor Vent Valve operation?
Only open early during start. Specifically closed when engine not running.
EBV Definition & Purpose
Engine Bleed Valve Bleed air from 9th or 14th stage for Pressurization & AC. 9th stage during start to assist w/ accelerating to idle RPM.
Ignition System
Two ignitors per engine. Wired to their associated FADEC. (FADEC A to IGNITION A) (FADEC B to IGNITION B)
When would you select ignition to the ON selection?
During Cold Start(OAT 10C or less & Cold Eng (shutdown for 90min)
Ground Cart Start
QRH
Valcanic Ash
Heavy Rain
When will you see ignition for a normal engine start?
Auto__14 - 56.4% N2 ON____10% N2
What is the purpose of Closed-Loop Fan Speed Control?
FADEC checks N1 request & actual N1, compares the two, then adjust fuel to make N1 = N1 request.
FADEC How many? Definition? Failure?
4 FADEC (2 per Eng.)

Full Authority Digital Electronic Control

If both FADEC's on one engine fail the engine will shutdown.
FADEC directs FPMU to provide fuel for:
Starting Operating Windmilling Shutdown CVG operation
What does the FADEC's need to know before each flight?
Thrust Setting
Temperature (w/ in 10C)
Anti-Ice ON or OFF
When will the FADEC shutdown an Engine in an Overspeed or Underspeed Condition?
MIN__54% N2 MAX__100% N1 or 102.4% N2
CVG Functions & Definitions
Compressor Varible Geometry 6 stages, driven by hydraulic system. Comanded by FADEC. Operated by high pressure fuel. Two Basic Functions: Efficiency & Prevents Compressor Stall
What is the purpose & operation of the Starter Control Valve(SCV)?
Regulates air supplied to the Air Turbine Starter (ATS). Electrically commanded, pneumatically operated & spring loaded to close position.
FPMU Definition & Operation
Fuel Pump & Metering Unit Electrical-Mechanical, Fully-Integrated line replaceable unit. High pressure pumps, meters fuel, filters fuel & operates CVG.
What is the purpose of the FPMU Low Pressure Centrifugal Pump?
Raises fuel pressure high enough to meet the requirements of the high pressure pump and ensures fuel is vapor free.
Describe High Pressure Compressor
14 stages CVG stators are provided for 1-5 stages & for inlet guide vanes. Controlled by the FADEC.
HPT Purpose
2 Stage High Pressure Converts gas flow coming from the combustion liner into usable mechanical energy to drive the compressor.
LPT Purpose
3 stages Extracts energy from the gas path to drive the FAN. LPT is connected to the FAN by means of a Shaft extending through the entire HP Spool & Compressor assembly. LPT & Bypass air provides thrust.
If DC's Fail, will your engine still run?
Yes, by using PMA's. (Permanent Magnetic Alternator)
When does PMA provide sufficient power?
Min 50%N2 for FADEC 10%N2 for Ignitors
What four items does PMA power?
FADEC's
Thrust Levers
Thrust Mode Buttons
Ignitors (PMA is the only power source)
Lubrication System
Oil Tank FCOC ACOC Gear Box
FCOC Definition & Function
Fuel Cooled Oil Cooler Cools engine oil & warms fuel. Fuel never bypasses.
Accessory Gear Box
Driven by HP Spool (N2) FPMU ATS Generators (2 DC) Hydraulic Pumps Oil Pumps PMA
Where is N2 picked up?
Accessory Gear Box
What happens if the tower shaft brakes?
Engine Failure, because FPMU is connected to the Gear Box.
Where are the 5 oil sumps?
FAN FWD CENTER AFT AGB
Engine Fuel System Components
FPMU
FCOC
CVG
16 Fuel Nozzle's
What happens if all three fuel pumps in each wing fail?
FPMU will provide suction to supply fuel to the engine.
What are the different idle speeds?
Ground Flight Flight in Icing Cond.
Ground Idle Logic
Avoid Flame Out.
Avoid Over Temp.
Bleed for ECS.
Gas Gen Speed to drive Accessories.
Flight Idle
Avoid Flame Out Over Temp. Bleed for ECS Full thrust in 8 sec.
Flight Idle in Icing Conditions
High thrust setting for Bleeds.

Inhibited when gear down below 15,000 ft.
What is ATTCS?
Alternate Takeoff Thrust Control System
When would ATTCS trigger?
One TLA less than 38 deg.
Inop Engine.
ATTCS not armed w/ in 2 sec of each other.
ATTCS isn't disarmed w/ both engines w/ in 2 sec.
What situation would command MAX T/O THRUST mode? (T/O-1)
Auto:
A/C Power Up.
ATTCS mode.
Below 15,000 ft w/ gear down.
Above 78deg TLA.

Manually:
T/O thrust button

Must use T/O-1 mode for takeoff on a Contaminated runway, Windshear or if Performance requires it.
What situation would command ALT T/O-1 mode?
Normal Takeoff Performance Allows ALT T/O-1 ATTCS Operational
When may you select CLB mode?
No Engine Inop. Above 500ft Gear Up or Above 1700ft Inhibited on the ground.
When may you select CRZ mode?
No Engine Inop. Above 500ft Gear Up or Above 1700ft Inhibited on the ground.
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