Engines Flashcards
What engines are installed
The Global Express is equipped with two Rolls Royce BR710 engines which consist of the power plant, the basic engine, compressor airflow control, the oil and the fuel system, the FADEC system, the engine control and engine indicating system, the starting/ignition systems, and the thrust reverser system. The aircraft engines, model BR700-710A2-20 are mounted on a pylon on either side of the rear fuselage. They provide 14,750 pounds of flat-rated thrust to ISA +20°C at sea level. The engine is a high bypass ratio turbofan with two rotating assemblies/spools, namely the low pressure (LP)/N1 spool and the high pressure (HP)/ N2 spool, each driven by the respective set of turbines through the corresponding coaxial shaft. In addition, the HP spool provides an external drive for the engine-driven accessories mounted on the accessory gearbox (AGB).
What flat grated thrust do they provide
The aircraft engines, model BR700-710A2-20 are mounted on a pylon on either side of the rear fuselage. They provide 14,750 pounds of flat-rated thrust to ISA +20°C at sea level.
What turbines are installed
The engine is a high bypass ratio turbofan with two rotating assemblies/spools, namely the lowpressure/N1 spool and the high-pressure/N2 spool. Each is driven by the respective set of turbines through the corresponding coaxial shaft. All air entering the engine air intake passes through the LP compressor (fan). It is then divided into the two main flows, the bypass airflow (the cold stream), and the core airflow (the hot stream). The core airflow passes through the high-pressure (N2) compressor which has ten stages. It then passes through the annular combustion chamber which is provided with 20 spray nozzles for supplying the engine with its fuel requirements.
Do i always put engine covers on
Yes
Do i 30 sec dry crank before start
Yes
Does ign swap every start
Yes, channel and igniters
What control over engine is there
N1 and EPR, through a switch
What must oil press be before shutdown
Above 25psi
When magenta colour is on EICAS what does it mean
Controllled by FMS
What is p0
Gets info from TAT3
What is P20 or P30
Inches datum behind p0
Also EPRA sensing
How many compressor turbine stages
The core airflow which now includes the products of combustion, flows through two stages of highpressure (HP) turbines and two more stages of lowpressure (LP) turbines. The core airflow next passes through the forced mixer where it meets the bypass air.
Where does core air pass through
The core airflow passes through the high-pressure (N2) compressor which has ten stages. It then passes through the annular combustion chamber which is provided with 20 spray nozzles for supplying the engine with its fuel requirements.
Are cowl doors pressure relief
Yes, most of them
What happens to press relief doors with lower cowls down
Check press relief doors after closure
What do i clean intake lip with
Use correct liquid and only so many polishes
Are engine cowlings interchangeable
No
Do upper and lower cowls have titanium shields
Yes in case of rotor burst
How many engine mounts
Engine Mounts
Figures A8 and A9 Two beams, namely the front and rear mounting beams are used to mount the engine to the airframe. Both of these beams are attached to corresponding hard attachment points on the pylon. A top link and a bottom link on each of the engine mounting beams is attached to the engine. The front engine mount beam incorporates a center thrust trunnion to bear the weight at the front of the VIEW FROM REAR Fuselage Frame at FS 925 SUPPORTS ENGINE FRONT MOUNTS For Training Purposes Only Copyright © Bombardier Inc. Jan 2010 engine as well as the thrust of the engine. A thrust strut is attached at a point adjacent to the rear face of the center thrust trunnion. The front mount carries the weight of engine front end and transmits engine thrust loads to the thrust strut, which in turn, transmits them to the airframe. The rear beam supports the engine weight at the rear, and allows axial expansion and contraction at the rear due to temperature transients. The front mount is protected by a firebox, which is also attached to the fixed cowl.
What is exhaust material
Exhaust Unit
Figure A10 The exhaust unit provides a continuation of the nacelle exterior aerodynamics at its outer surfaces. At its internal surfaces, it acts as a collector for exhaust gases discharged by the engine, with the rear end of the unit acting as a propelling nozzle. The exhaust unit is bolted to the rear flange of the structural bypass duct module. The fixed structure and reverser door inner surfaces are constructed Thrust Reverser Bypass Duct Rear Support Ring from noise attenuating material. The oil system breather pipe passes through the exhaust unit and discharges overboard on the outboard side of the engine. It should be noted that for installation or removal of this unit during the buildup or dismantling of a power plant, all attachment items which require access are positioned on the top, bottom and outboard side of the unit, except for the inboard primary thrust reverser lock mechanism.
How many bearings
There are five main bearings (numbered 1 to 5 from the front) contained in two bearing chambers. Bearings 1, 2 and 3 are in the front bearing chamber (FBC). Bearings 4 and 5 are in the rear bearing chamber (RBC). Each rotating assembly is supported at the front by a ball bearing, which also transmits axial loads, and at the rear by a roller bearing. The LP spool has an additional roller bearing (no. 2) for support. Each bearing chamber is supported by the fixed structure of the engine, which passes all loads (thrust, weight etc.) into the airframe pylon via the engine mounts. Engine rigidity is enhanced by use of a structural bypass duct attached to the forward and rear fixed structures, at the front and rear of the engine.
Are blades etched
Yes 1 ,2 and 3, in CCW direction from front ,fwd looking aft
How many modules
7
What are modules
Engine Modules
Figure B2
The engine is made up of seven modules, as follows:
1. Module 31 – fan blade and disc assembly
2. Module 32 – intermediate case, radial drive, FBC (internal gearbox)
3. Module 33 – high-pressure compressor
4. Module 34 – fan case
5. Module 41 – high-pressure turbine and combustion chamber
6. Module 51 – low-pressure turbine and shaft
7. Module 61 – accessory gearbox (AGB)
How many outlet guide vanes
51 Lpg turbine outlet vanes
How many fan blades
Module 31 – Fan Assembly Figure B3
This module compresses the air entering the engine inlet cowl and feeds a portion of it to the engine core, while the remaining (bypass) air provides 85% of the engine’s thrust via the bypass duct. The various components of this module are: 24 solid wide chord blades with dovetail root location
24 annulus fillers providing smooth airflow into core engine Fan Case Module M34 Fan Blade (24) Nose Cone (Spiner) and Fairing FAN DISC AND BLADES BASIC ENGINE
Fan disc
Fan blade retaining ring which also retains the annulus fillers Fan disc bolted to fan shaft (see Module 32) by means of a curvic coupling
Retaining ring for the fan blades which also locates the (nonmodular) spinner Fan trim balance weights are fitted behind the spinner fairing. Fan blade numbers 1, 2, and 3 are etched onto the front face of the fan disc. Blades are numbered in a counterclockwise direction, as viewed from the front.
Does it have a turbine shaft breakage mechanism
Yes on LP turbine
What is module 61
Module 61
Accessory Gearbox
Figure B11
The accessory gearbox (AGB) transmits the driving force from the engine to the accessories mounted on the AGB. The AGB also transmits power from the air starter to the engine during start/crank procedures. In addition, the AGB houses the integral oil tank, and provides a means of hand turning the engine HP system for maintenance operations.
Two standards of AGB are approved for the BR710 engine. The baseline AGB has a cast magnesium housing.
An aluminium accessory gearbox is introduced, starting at
A/C 9251.
The accessory drives are the same on both AGBs. The AGB is bolted at the 6 o’clock position of the Fuel Metering Unit Variable Frequency Generator Fixed Mount Lugs No. 2 / 3 Dedicated Generator HP Shaft Drive Input Oil Pump Unit Fuel Pump Unit Air Turbine Starter Drains Mast (Ref) Hydraulic Pump TOP VIEW Fig. B11:
Module 61
Accessory Gearbox ATA 71 Page B-12 BASIC ENGINE intermediate module via two brackets, and is driven by the radial drive shaft. The AGB drives the following units:
Variable frequency generators (2 ea.)
Air turbine starter
Fuel pump and fuel metering unit
Oil pump unit
Hydraulic pump
Dedicated generator
Oil breather (internal) Access for turning the N2 (or HP) spool is through a plate on the rear face of the oil breather outlet. An AGB magnetic chip detector is located at the center of the AGB rear face.
Does Agb have a designated generator
Yes
What is structural bypass duct
Structural Bypass Duct Figure B13 The bypass duct is a structural engine component that provides a streamlined path for the fan bypass airflow and supports the thrust reverser unit. It also provides mounting features for many components related to the engine systems. The bypass duct is a single piece composite structure that bolts directly onto the rear flange of the intermediate module outer casing. It is bolted to the rear flange of the bypass duct is the rear support ring. The rear support ring is the attachment point for the core engine support struts on the inside. It also serves as the load-bearer for the thrust reverser unit, the core engine rear end and the rear engine mounts. Openings (with cover panels) in the bypass duct allow access to several core mounted system components. The system components are the bleed valve solenoid unit, VSV actuator, fuel spray nozzles, igniters, and ITT thermocouples.
There are two variable frequency generator oil coolers (surface air cooled oil coolers). They are mounted on the inside surface of the structural bypass duct towards the rear. The bypass duct is protected from overheating due to malfunctions/ fires of externally mounted components by a special blanket wrapped around the bypass duct.
How many panels on structure bypass duct
10 access panels
How many borescope ports
Engine Borescope Access
Figure B16 Provision is made at various positions on the core engine to enable borescope inspection equipment to be used to visually examine a representative number of internal features. The LP system is rotated by turning the LP compressor blades by hand. The HP system is rotated by removing the accessory gearbox (AGB) breather cover and inserting a splined turning tool into the breather drive shaft. The turning tool flange is bolted to the breather and a standard ratchet drive fitting is used to rotate the tool and HP system.
Engine stations are as illustrated in figure B16. A brief synopsis of the access to the various ports is as below:
B & C: Two ports per stage, at 3 o’clock and 9 o’clock positions; access is via individual small cover plates in the bypass duct.
D & E: Two ports per stage, at 3 o’clock and 9 o’clock; access is via the forward and middle bypass duct access panels.
F: Accessed through the two igniter plug holes, via the forward and middle bypass duct access panels.
G & H: One port per stage, at the 7 o’clock position.
How is the cooling air configured
COOLING AND SEALING AIR Figures B17 and B18
The engine is cooled internally with air that is tapped from different stages of the HP compressor. Parts of the engine that are at different pressures are isolated from each other by labyrinth seals. Air is taken from the fan bypass and from the HP compressor stages 2, 4, 6 and 10 for engine internal cooling and sealing purposes, including sealing of the accessory gearbox (AGB)
Does fan air cool
Fan Air Fan air flows through the turbine outlet guide vanes (OGVs), first to cool the OGVs and then the rear face of the LP turbine stage 2 disc and thereafter, the air baffle and the stirrup assembly of the emergency fuel shutoff system.
The fan air next flows into the engine exhaust gas stream between the lp turbine stage 2 blade roots and the turbine outlet guide vanes
What does HP2 air cool
The FBC and AGB seals are fed by either HP2 air (at high engine power settings) or by HP4 air (at lower power settings). The changeover between HP2 and HP4 air is achieved through a buffer air valve which operates in conjunction with the variable stator vane (VSV) actuator mechanism.
What does HP6 air cool
HP6 Air Figure B17 An inward flow of HP stage 6 bleed air provides intershaft sealing of the FBC, cools the HP compressor discs and inside of the HP compressor drum, cools HP turbine discs and pressurizes the intershaft seal of the RBC. The air also cools the LP turbine discs, and flows into the engine exhaust gas stream between the LP turbine blade roots. The RBC HP6 air exhaust is monitored to detect turbine overheat by means of a detector. This subject is discussed in greater detail in subsequent paragraphs.
