keesje
Topic Author
Posts: 8748
Joined: Thu Apr 12, 2001 2:08 am

Will The PW1000G Trump The CFM Leap-X?

Tue Aug 31, 2010 2:53 pm

The GLGroup has become a bit less predictable recently, apparently some new experts joined the group. There is a new article on the Pratt & Whitney PW1000G versus GE LEAP-X competition. http://www.glgroup.com/News/Why-the-...CFM-Leap-X---Innovation-50296.html

Those two new engines (and their customers) have been causing some uproar in until recently peaceful NB segment. The author is (very) convinced the PW1000G series is on the winning hand and he explains why;

   revolutionairy technology instead of evolutionairy
   larger thrust range (up to 40k lbs)
   potential to further lower fuel burn



Myself I tend to give the LEAP-X the benefit of the doubt based on the CFM Safran+GE) track record, GE's GENX technology and a natural skepticism about a hot running gearboxes in compressor inlets.

Last week Airbus John Leahy said he is "comfortable" with Pratt & Whitney's P1000G maintenance projections of 20% lower maintenance costs compared with today's engines and that Airbus tests of a P1000G on an A340-600 testbed support Pratt's claims. http://www.flightglobal.com/articles...ave-7-8-million-price-premium.html



Now I'm not so sure anymore..
"Never mistake motion for action." Ernest Hemingway
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 1:11 am

Quoting keesje (Thread starter):
potential to further lower fuel burn

I think this applies to the Leap-X as well, so I'm not sure why they're giving that to the GTF.

It's an interesting fight, since the two companies are tacking the same problem (fuel burn) via two different paths. One is going after propulsive efficiency, one after thermodynamic efficiency. Both are viable paths and it's a question of which company can push farther down their respective roads.

One advantage I think Leap-X has is that that technology would scale to a new large engine a lot more easily than GTF would.

Tom.
 
User avatar
Stitch
Posts: 23081
Joined: Wed Jul 06, 2005 4:26 am

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 1:21 am

Quoting tdscanuck (Reply 1):
One advantage I think Leap-X has is that that technology would scale to a new large engine a lot more easily than GTF would.

Pratt believes that the GTF can scale to over 100,000 pounds for use on the 777 and they note the bigger the fan, the shorter the engine (relative to a conventional engine) because they reduce engines stages along with their attendant discs and airfoils. So the bigger the engine, the lighter it gets and the less maintenance it needs compared to a conventional engine.
 
rheinwaldner
Posts: 1249
Joined: Wed Jan 02, 2008 4:58 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 7:12 am

Quoting tdscanuck (Reply 1):
One is going after propulsive efficiency, one after thermodynamic efficiency

How good would be a combination of both?
 
keesje
Topic Author
Posts: 8748
Joined: Thu Apr 12, 2001 2:08 am

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 7:51 am

Quoting rheinwaldner (Reply 3):
How good would be a combination of both?

That's what I wonder about too, it seems much of the technology used by CFM and PW , doesn't exclude each other.

A Leap-X with a geared turbofan and a slower more efficienct and silent airstream / more optimized hot section RPM's, why not..
"Never mistake motion for action." Ernest Hemingway
 
sirtoby
Posts: 347
Joined: Sat Nov 10, 2007 11:56 am

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 9:23 am

Quoting tdscanuck (Reply 1):
One advantage I think Leap-X has is that that technology would scale to a new large engine a lot more easily than GTF would.

The LEAP-X is more or less a downscaled version of the GEnx...

Quoting tdscanuck (Reply 1):
Quoting keesje (Thread starter):
potential to further lower fuel burn

I think this applies to the Leap-X as well, so I'm not sure why they're giving that to the GTF.

If you are already running hot that is harder to achieve as you cannot get very much hotter as you then would hurt maintenance costs and your NOx emissions go up.
 
aerotech777
Posts: 71
Joined: Sat Aug 15, 2009 3:53 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 2:28 pm

Hi,

It was mentioned in the first link that the core of the Leap X will use the concepts from lower cycle wide body engines and apply them higher cycle narrow body environment. It will be nice if some engine gurus can post some details about these concepts.

In the same link it was also mentioned that the Leap X will use 2 stages high pressure turbine instead of single stage. What%u2019s the benefit of the use 2 stages HP turbine versus single stage and is this related to lower cycle versus higher cycle?

Feedback appreciated.
Regards
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 2:40 pm

Quoting rheinwaldner (Reply 3):
Quoting tdscanuck (Reply 1):
One is going after propulsive efficiency, one after thermodynamic efficiency

How good would be a combination of both?

The benefits should be cumulative...they're basically independent technologies.

Quoting keesje (Reply 4):
it seems much of the technology used by CFM and PW , doesn't exclude each other.

Agreed.

Quoting aerotech777 (Reply 6):
It was mentioned in the first link that the core of the Leap X will use the concepts from lower cycle wide body engines and apply them higher cycle narrow body environment. It will be nice if some engine gurus can post some details about these concepts.

The major drive on Leap-X is to carry all the latest aerodynamic improvements (most of which have come on large engines recently) back into the smaller engines, like 3D airfoils and improved combustors, plus a higher pressure core (greater thermodynamic efficiency).

Quoting aerotech777 (Reply 6):
In the same link it was also mentioned that the Leap X will use 2 stages high pressure turbine instead of single stage. What%u2019s the benefit of the use 2 stages HP turbine versus single stage and is this related to lower cycle versus higher cycle?

I don't think it's a benefit so much as a necessity. Higher thermodynamic efficiency requires a higher pressure ratio, which requires a more powerful compressor, which requires more turbine to drive the more powerful compressor. If you can't get enough power extraction from a single stage, you go to two.

I don't think these particular design features are particularly cycle related.

Tom.
 
keesje
Topic Author
Posts: 8748
Joined: Thu Apr 12, 2001 2:08 am

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 3:59 pm

UTC seems to all but confirm Airbus has approved their GTF as a 3rd engine option.

http://www.automatedtrader.net/real-...nfident-airbus-will-re_engine-a320
"Never mistake motion for action." Ernest Hemingway
 
Lumberton
Posts: 4176
Joined: Fri Jul 29, 2005 7:34 am

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 9:06 pm

Quoting keesje (Thread starter):
The GLGroup has become a bit less predictable recently, apparently some new experts joined the group.

They're not new; they've been with GLG for some time. Anyway, here's the other side of the GLG debate on which of these engines looks more promising.
http://www.glgroup.com/News/CFM-Inte...ything-But-A-Derivative-50258.html

Quote:
There is nothing worse than misinformation, so let’s clear up a few issues. For those of us who bothered to go to the Farnborough Air Show, then like me, you’ll have known that the CFM International LEAP-X engine is not a derivative engine. It is a brand new engine from the ground up.

In contrast, the Pratt & Whitney GTF engine is a derivative engine – the geared engine concept is a 1960s based design, compromised, risky and airlines have witnessed issues with reliability with such designs before. The LEAP-X engine is a new product launched in 2008 – hardly the definition of derivative when even CFM doesn’t even have a related engine to it.

If any engine is going to reach limitations first, it’s the GTF. Don’t be duped by claims that the LEAP-X engine cannot be expanded. When speaking extensively the LEAP-X program director, at the show, he informed me that the demonstrator testing had exceeded expectations, was ahead of the planned development timeline and has scope to grow in both thrust and further fuel burn reduction.
"When all is said and done, more will be said than done".
 
Nicoeddf
Posts: 513
Joined: Thu Jan 10, 2008 7:13 am

RE: Will The PW1000G Trump The CFM Leap-X?

Wed Sep 01, 2010 9:54 pm

Quoting aerotech777 (Reply 6):
In the same link it was also mentioned that the Leap X will use 2 stages high pressure turbine instead of single stage. What%u2019s the benefit of the use 2 stages HP turbine versus single stage and is this related to lower cycle versus higher cycle?

Not to mention that CFMI is at the absolute limit of material technology regarding their HPT Blades on the CFM56-5A/B.
The one stage has to drive the complete HPC with the result that there is apparently so much load on the one stage, that CFMI up to now is not capable of producing a reliable blade (not even the latest and greatest P/N).
That leads to a soft time limit on the blades (12.000 cyc?!) and a lot of HPT blade separations in the past beginning from cracks at the platform.

Not to nice and airlines are not happy...

Interestingly enough, the V2500 engine has two stages, as do all bigger engines apart from Rolls Royce with their triple spool design and their single stage HPT + single stage IPT, resulting effectively in load distribution of the compressor system to two stages also.
 
keesje
Topic Author
Posts: 8748
Joined: Thu Apr 12, 2001 2:08 am

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Sep 02, 2010 10:34 am

Quoting Lumberton (Reply 9):
Anyway, here's the other side of the GLG debate on which of these engines looks more promising.

Doesn't sound like a very proffesional editorial. He/she attack someone;

Quoting Lumberton (Reply 9):
There is nothing worse than misinformation, so let’s clear up a few issues. For those of us who bothered to go to the Farnborough Air Show, then like me, you’ll have known that the CFM International LEAP-X engine is not a derivative engine. It is a brand new engine from the ground up.

Who claimed the Leap-X is a derivative ?! Haven't seen it anywhere! Talking about misinformation, what a Don Quixote.

Then to claim the PW1000G is a derivative because gearboxes were tested in the sixties, I won't even go into that..

+ I have spoken to a saleman at an airshow so I know, too funny.
"Never mistake motion for action." Ernest Hemingway
 
aerotech777
Posts: 71
Joined: Sat Aug 15, 2009 3:53 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Sun Sep 05, 2010 4:30 pm

Hi,

I am wondering why the aft part of PW 1000G engine cowl is moving according to this link:
http://www.youtube.com/watch?v=vgQgEftEd8c
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: Will The PW1000G Trump The CFM Leap-X?

Sun Sep 05, 2010 5:57 pm

Quoting aerotech777 (Reply 12):

I am wondering why the aft part of PW 1000G engine cowl is moving according to this link:

I don't know for sure, but I can think of two possible reasons offhand:
1) They're trying to define the optimum fan duct profile and, by putting different "rings" on the aft end of the nacelle and then sweeping them fore/aft they can track TSFC and find the optimum.
2) They're actually implemented a very simple variable area nozzle for production, which would allow them to tweak the fan stream exit velocity in flight and squeak out a small propulsive efficiency gain.

Tom.
 
Bogi
Posts: 451
Joined: Sun Sep 09, 2001 5:00 am

RE: Will The PW1000G Trump The CFM Leap-X?

Fri Sep 27, 2013 1:33 pm

MTU: PW 1000G engine is an unexpectedly huge success.
http://www.youtube.com/watch?v=BwfagWEabi4
 
User avatar
Francoflier
Posts: 3702
Joined: Wed Oct 31, 2001 12:27 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Fri Sep 27, 2013 6:07 pm

Quoting Bogi (Reply 14):

Nice thread digging.  

Any highlights of the interview for us non-teutons?


I am a big fan of the geared fan...
Even though CFM has managed to keep up orders-wise thanks to the NEO and being the only supplier on the MAX, I believe the geared technology will eventually mature and benefit from the thermodynamic advances of the LEAP, giving it the best of both worlds.

Whereas it feels like the LEAP is squeezing conventional engine technology, the PW 1000G, on the other hand, still has a lot of room for improvement.

Go PW.
I'll do my own airline. With Blackjack. And hookers. In fact, forget the airline.
 
Bogi
Posts: 451
Joined: Sun Sep 09, 2001 5:00 am

RE: Will The PW1000G Trump The CFM Leap-X?

Fri Sep 27, 2013 7:06 pm

Quoting francoflier (Reply 15):
Any highlights of the interview for us non-teutons?

Only a written summary in German.

http://www.aero.de/news-18251/MTU-Pu...wer-PW1000G-ein-voller-Erfolg.html

You can translate it with goggle.
 
LH707330
Posts: 1498
Joined: Fri Jun 15, 2012 11:27 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Fri Sep 27, 2013 8:09 pm

Quoting francoflier (Reply 15):
Any highlights of the interview for us non-teutons?

I thought there were enough Anglicisms in there like "fan" and "open rotor" that it was half English anyway  Give it another 10 years and all the complicated descriptive words (Mantelstromtriebwerk) will be replaced by their English equivalents (Turbofan).

Joking aside, Dr. Henne discusses the overall market for the GTF (platforms, basic structure, etc.) and moves on to talk about the future of the GTF. What I found most interesting were four main points he made near the end:
1. GTFs will become much more efficient when the fan and nacelle weight can be reduced, thus allowing larger fan diameters to become more feasible
2. GTFs are only in the beginning of their development cycle, and will benefit greatly from further optimizations, especially for widebodies
3. Open rotors are a riveting/exciting (German "spannend") development, but likely won't be around for at least 12-15 years. Obstacles to adoption include noise, mounting issues (the need to co-optimize plane and engine), and #1 eroding the advantages of OR vs. GTF
4. Thermodynamic improvements in the form of heat exchangers will enable further increases in efficiency in the future

The first three of these points seem relatively straightforward to understand, what I'd like to understand more about is the heat exchanger technology, especially given the recent comments round about the water injection in the GE9X. Would it make sense to have a fuel-cooled intercooler somewhere in the HPC to take heat energy out of the incoming air to lower pressure and thus reduce work load (=fewer HPC stages) while maintaining core mass flow, and then re-introduce this heat energy in the form of heated fuel in the combustor?
 
User avatar
KarelXWB
Crew
Posts: 19948
Joined: Sun Jul 15, 2012 6:13 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 11:08 am

I'm bumping this topic. It seems the CFM Leap engine is missing its SFC spec by a large margin: up to 5% for the 1B model (737 MAX) and up to 2% for the 1A model (A320neo).

http://aeroturbopower.blogspot.com/2...15/03/cfm-leap-1b-missing-sfc.html
Close, but no cigar http://vine.co/v/OjqeYWWpVWK
 
TheSonntag
Posts: 4303
Joined: Wed Jun 15, 2005 7:23 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 11:25 am

I started a thrad in Civ av about it, too (mentioning that you brought forward this information).
 
tommy1808
Posts: 4010
Joined: Thu Nov 21, 2013 3:24 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 12:23 pm

Quoting KarelXWB (Reply 18):
up to 5% for the 1B model (737 MAX) and up to 2% for the 1A model (A320neo).

I wouldn't want to be the sales guy that has to convince customers that 5% can be made up near term. That is about of 10 years worth of normal engine development, isn't it?
So, the 738maxerx just lost ~200nm range.....?

Best regards
Thomas
 
User avatar
seahawk
Posts: 3422
Joined: Fri May 27, 2005 1:29 am

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 12:33 pm

And 5% might be more than 5% when you compare it to a GTF A320, considering that rumours say that PW is exceeding expectations.
 
parapente
Posts: 1280
Joined: Tue Mar 28, 2006 10:42 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 12:59 pm

How interesting to see what was said then and now.This will become a hot topic!
 
User avatar
Francoflier
Posts: 3702
Joined: Wed Oct 31, 2001 12:27 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 1:47 pm

Quoting seahawk (Reply 21):
considering that rumours say that PW is exceeding expectations.

And that's with the first iteration of it.

I expect they will be able to squeeze a lot more from it through PIPs and enhancements.
It is my uninformed understanding that PW has put a lot of effort into designing the geared fan and that, as a result, the compressor and hot section are not exactly state of the art compared to the LEAP.

It will be a great engine with lots of space for improvements.

As for CFM. Well, they have their work cut out. I don't expect they will be able to easily push another 5% efficiency on a design that's already cutting edge technology in the field.
At least they have solid financials and credentials, a large network and plenty of loyal customers...
I'll do my own airline. With Blackjack. And hookers. In fact, forget the airline.
 
User avatar
KarelXWB
Crew
Posts: 19948
Joined: Sun Jul 15, 2012 6:13 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 2:51 pm

Quoting francoflier (Reply 23):
I expect they will be able to squeeze a lot more from it through PIPs and enhancements.

Pratt is working on another 2% improvement due in 2019.

http://www.flightglobal.com/news/art...upgrade-for-a320neo-engine-396062/
Close, but no cigar http://vine.co/v/OjqeYWWpVWK
 
parapente
Posts: 1280
Joined: Tue Mar 28, 2006 10:42 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 4:49 pm

Re Link post 25 (thanks)
Phenomenal performance (to date).All helps the A321 NEO LR cause.
Makes me think that the new GE engine for the 777X and the potential 'Advance' for the 380 will be the final iterations of large fan engines using a 'direct drive' design. I am advised that it is a far bigger issue gearing such powerful engines but none the less.Such savings are massive it can only be a matter of time. (Although probably quite a bit of time - however they will probably need it).
 
LH707330
Posts: 1498
Joined: Fri Jun 15, 2012 11:27 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 5:29 pm

Quoting parapente (Reply 25):
I am advised that it is a far bigger issue gearing such powerful engines but none the less.Such savings are massive it can only be a matter of time. (Although probably quite a bit of time - however they will probably need it).

PW has said they can go to 70k and change the ratio from a 3:1 up to a 4.5 or 5:1. I think they've got their hands full executing on the current-gen GTFs, but I bet they've got something in the pipeline. The problem is that all current frames have an engine, so they missed the boat for now.
http://aviationweek.com/commercial-a...s-pw-a330neo-a380-reengining-plans
 
User avatar
Revelation
Posts: 13841
Joined: Wed Feb 09, 2005 9:37 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Thu Mar 19, 2015 6:35 pm

Quoting KarelXWB (Reply 18):
I'm bumping this topic.

Bump indeed, the thread was started by keesje in 2010!

Quoting tommy1808 (Reply 20):

I wouldn't want to be the sales guy that has to convince customers that 5% can be made up near term. That is about of 10 years worth of normal engine development, isn't it?

I think you can't apply the same figure to post-release development vs pre-release development. Not saying that 5% gain is ever easy, but it's a lot harder if you've already got a certified engine out in the field and really can't change major aspects of the design.

Quoting LH707330 (Reply 26):

PW has said they can go to 70k and change the ratio from a 3:1 up to a 4.5 or 5:1. I think they've got their hands full executing on the current-gen GTFs, but I bet they've got something in the pipeline.

I can't search for the links now, but I've seen press reports that PW corporate (UTC) is wanting to reduce its spend on R&D as well. I think they want to reap some rewards of spending $billions on GTF before they launch a new platform.

[Edited 2015-03-19 11:38:59]
Inspiration, move me brightly! Light the song with sense and color.
Hold away despair, more than this I will not ask.
Faced with mysteries dark and vast, statements just seem vain at last.
Some rise, some fall, some climb, to get to Terrapin!
 
User avatar
lightsaber
Crew
Posts: 11830
Joined: Wed Jan 19, 2005 10:55 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Tue Mar 24, 2015 4:48 am

When I saw this thread, I thought it was with a more recent start date.  
Quoting TheSonntag (Reply 19):
I started a thrad in Civ av about it, too (mentioning that you brought forward this information).

What happened to that thread? It seems there is a group who only want photos, liveries, and uniforms in the civil aviation forum.  

Come on! Its all about engines.  
Quoting LH707330 (Reply 26):
The problem is that all current frames have an engine, so they missed the boat for now.

It also is guessing the thrust as each ratio of gearbox is only good over a range of thrusts. Pratt must develop the gearbox for years before initiating engine development. Right now they are focused on a 3.5:1 gearbox that should be good for up to 65k of thrust and down to about 30k.

Quoting Revelation (Reply 27):
I've seen press reports that PW corporate (UTC) is wanting to reduce its spend on R&D as well.

Pratt has to refocus resources on manufacturing. The reality is Pratt has an amazing production ramp they must get through. It is a challenge I think they are good for.

Lightsaber
"They did not know it was impossible, so they did it!" - Mark Twain
 
TheSonntag
Posts: 4303
Joined: Wed Jun 15, 2005 7:23 pm

RE: Will The PW1000G Trump The CFM Leap-X?

Tue Mar 24, 2015 9:33 am

Quoting lightsaber (Reply 28):
What happened to that thread? It seems there is a group who only want photos, liveries, and uniforms in the civil aviation forum.

Mods moved it. As I said in the other thread, no comment on that from me.

Who is online

Users browsing this forum: Alexa [Bot] and 16 guests