The Aircraft Manufacturer has an Option on a Few Powerplants that are Designed Taking into Account the Thrust & SFC requirements for the Model concerned.The Powerplant manufacturers come up with a Product if it meets the criteria of the Aircraft Manufacturers.It would be selected.

More than one Selection givres the Customers an option of Choice.Taking into Account cost,Stores Inventory & other data to enable the best Selection.

regds

MEL

Thanks for the replies guys.....

Any more inputs, before some considerable research is put here.

HAWK21M wrote:

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A320 Family A319-A321 options are CFM56Bs & IAI V2500s

Only the A318 has CFM56Bs & P&W6000.

regds

MEL

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HAWK21M wrote:

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For B737NGs options are CFM56-7B

The B737-300/400/500s had CFM56-3C

The B737-100/200 had P&W JT8D-7/7A/9/9A/15/15A/17/17A/17R

B757-200 have RB211-535C/E4 & P&W 2037/40.

regds

MEL

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Thanks Mel. I appreciate ur help.

Adding Bleedless engines information here itself :

Knowing that from the current engines Engine bleed is used to pressurize the pneumatic system. That system does several things. To name a few, but not all inclusive, provides air for cabin heating/cooling and pressurization via the air con packs, wing and engine anti ice, pressure to water system, head pressure on hydraulic resevoirs. 

We all hear that the B787 will be using bleedless engines and when it comes to engines and fuel....im always around so here it is.

Bleedless engines  is one that doesn't supply air from the internal flow of the engine to the pneumatic system of the aircraft. All of the air entering a bleedless engine will be used to create thrust, excepting a small amount of air for internal cooling and engine stability.

The main advantage of a a bleedless engine is efficiency because a lot of hot air is dumped overboard in the process of supplying pneumatic functions to an aircraft. Now this is wasted energy.The electrical pneumatic systems that will replace bleed air systems will be much more efficient and that what we will have to wait and see. Now if the engines are just used for thrust purposes and no secondary duties then fuel efficiency of an engine increases and yes even if 3% of better efficiency means whole lot of money that can be saved .

The other advantage i can see is that the valves and ducting will be mostly eliminated.Weight may also be saved by eliminating these components.

So in short :

In commercial aircrafts, BLEEDLESS ENGINES primary use is to provide hot air for heating the inside of the plane (since at cruising altitude, the ambient temperature is around -50°C), as well as for providing pressure for the cabin.

Also primarily bleed air is used to keep critical parts of the aircraft (such as the wing leading edges) ice-free.

But my research and study reveals me to ask this question :

Does a bleedless engine mean that there will be more electrical parts as most of the fuel related functions will be lessened and thereby reducing load on the engine?

How much weight will be added by the electrical systems including generators, etc if bleed air is no longer used for heating/cooling, de-icing, etc? Will the difference be substantial?

vivekman wrote:

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How much weight will be added by the electrical systems including generators, etc if bleed air is no longer used for heating/cooling, de-icing, etc? Will the difference be substantial?

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I believe, Wing & Engine anti-ice will end up using electrical heating with boots, back to old tech. Things to look for here is the risk of damage to boots and wires from FOD. 

Packs will have dedicated turbo-chargers to supply air, these will be mounted alongside the packs to eliminate ducting and any losses in routing. Tapping from here will end up pressurising water and hydraulic reservoirs. Here system redundancies will have to be weighed, will a single compressor feed say 2 packs with a back-up. How does this affect ETOPS ? Since the B787 is a twin engine aircraft.

Engine is bleedless as far as customer bleed is concerned, however airflow control and Turbine Case Cooling will require bleed air from the engine. Probably Engine anti-ice might end up using a tapping from the engine, as the risk of FOD to nacelle boots is higher in the case of the engines. 

Customer bleed system is quite weight and maint intensive and also complex for system monitoring i.e. OVHT warn. 

Last but not the least engine start, how big (wt) is this electric start motor going to be to generate sufficient torque to turn the engine, will it require more complex(wt) gear box.

Pls share your findings here jumbo........i am sure this must have been discussed on a.net.

Good luck.

My research is at its brink stage. Another week should reveal the truth (or atleast my perspective).

A total of 320 pages have been compiled. Some edition and conciseness has to be done. Shall upload the final version via a pdf link.