GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 28 Mar 2019, 22:54
by spazsinbad
GE Aviation’s future fighter engine TECHNOLOGY XA100 [FOUR PAGE PDF of Article attached below]
April 2019 Chris Kjelgaard

"Completion by GE Aviation of the detailed design process for its adaptive-cycle fan engine signals a switch from technology development to ensuring manufacturing readiness, reports Chris Kjelgaard...

...In completing the detailed design of the XA100, according to Tweedie, the company has moved on to a new phase of development from the primary technology-development effort in which it has been involved for the past 12 years to design and mature a variable-cycle fighter engine based on an adaptive-cycle fan design. Its XA100 design having been approved by the US Air Force, GE has now embarked on the final push to complete Phase 1 of the two-phase AETP programme. This push represents the final maturation of adaptive-cycle fan engine development to the point where an XA100-sized engine can be placed quickly—and with very little technological and design risk—into volume production if required, said Tweedie....

...Along with Pratt & Whitney’s XA101 variable-cycle engine, GE Aviation’s XA100 is one of two adaptive-cycle fan engine designs competing for what may eventually be a decision by the US Air Force to order just one variable-cycle fighter-engine design into production based on the service’s findings from AETP Phase 1. In 2016, the AFLCMC awarded each of the two companies a $1 billion, five-year R&D contract under AETP Phase 1 so the US Air Force could choose a potential winner from the XA100 and XA101 and order it into production during the first half of the 2020s.

As finally became clear publicly in mid-2018, the US Air Force specifically had in mind a potential decision to re-engine the Lockheed F-35 from about 2025 onwards, partly as a result of the known thermal-management challenges the F-35 has today in combination with its existing F135 engine. To that end, the AFLCMC specified that not only must the XA100 and XA101 fit the space within the F-35 that the F135 occupies today, but it also required the competitors’ variable-cycle engines to demonstrate a 10% maximum thrust increase over the F135, along with a 25% fuel-efficiency improvement and the capability to give the F-35 a 20% range increase.

Also specified, but not in a manner relayed publicly, is that the AETP Phase 1 competitors must provide the F-35 with substantially, perhaps very dramatically, improved thermal management capabilities. Of necessity, those thermal-management capability improvements require that both AETP Phase 1 competitors work very closely with F-35 airframe manufacturer Lockheed Martin to integrate the airframe and its systems with the engine and its systems to an extremely high degree....

...Air Force thinking
Although the AETP R&D programme began in 2016 and specified an adaptive-cycle fan engine which was of the same dimensions as the F135 powering the F-35, the US Air Force and its two AETP contractors said at that time the specification merely served as a convenient reference point for GE Aviation and P&W to assist them in developing their respective AETP Phase 1 engines.

Indeed, each of the two contractors was allowed to inform the AFLCMC of its preference regarding the AETP engine’s physical size and reportedly each asked to be able to develop an F-35-compatible engine. Not until two years later did GE Aviation, in the person of then-GM advanced combat engines Dan McCormick, first confirm publicly—with the US Air Force’s permission—that the AFLCMC had deliberately specified the AETP Phase 1 engine so that it could potentially serve as an F135 replacement.

Asked by AIR International why the US Air Force took this course, Tweedie said it had not wanted at the time to focus public attention specifically on a potential re-engining of the F-35 because the service had believed strongly for years—and had said publicly—that it believed variable-cycle engines would be fundamentally important for all of its future fighter aircraft. When the AETD programme began in 2012, the US Congress had asked about the purpose of the programme and even then the US Air Force indicated it thought adaptive-cycle engines represented the future for all of its fighter types, according to Tweedie.

Before the AETP programme began in 2016, the service had indicated the 10% thrust-increase requirement and the 25% fuel-efficiency improvement “would be foundational for the Air Force to have superiority against adversaries,” Tweedie said. “Neither in words nor actions has the Air Force done or shown anything other than what it said then — this is the future for all our products.”...

...variable-cycle engine technology, which employs at least three airstreams to enhance performance and efficiency throughout the flight envelope, represents the future for military high performance engines, the US Air Force believes. “This is the foundation of a whole new family [of engines] that will mature over the coming decades,” until eventually it too matures to the point where further rapid performance improvement becomes extremely difficult, said Tweedie. “That thinking is what has driven a lot of this [variable-cycle engine R&D] and a lot of the [US] Air Force’s investment in this technology.”"

Source: AIR International APRIL 2019 Vol.96 No.4

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 29 Mar 2019, 03:18
by Dragon029
I wonder whether either this 20% or earlier 30% range increase figures were made in error. Either one could make sense depending on what airspeeds and altitudes the peak efficiency figures are being reached at. Even if it is 20%, that could potentially mean greater loiter capability, or it could make the F-35 able to / better at supercruising, depending on how the 3rd stream is configured and sized, what regime the fan is optimised for, etc.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 29 Mar 2019, 22:27
by wrightwing
Dragon029 wrote:I wonder whether either this 20% or earlier 30% range increase figures were made in error. Either one could make sense depending on what airspeeds and altitudes the peak efficiency figures are being reached at. Even if it is 20%, that could potentially mean greater loiter capability, or it could make the F-35 able to / better at supercruising, depending on how the 3rd stream is configured and sized, what regime the fan is optimised for, etc.

I'm not sure about the phase 1 motors, but have seen figures like 20% thrust increase, 50% loiter increase, and 30 to 35% range increase, for proposed phase 2 motors.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 29 Mar 2019, 22:50
by spazsinbad
Detailed Design Complete for GE’s Revolutionary Adaptive Fighter Engine [short & sweet artickle]
01 Mar 2019 Nick Zazulia

"GE Aviation has completed the detailed design process of its XA100 engine under the U.S. Air Force's Adaptive Engine Transition Program (AETP), the company announced Thursday. The latest development means that GE can send engineering drawings out to its supply chain to get engine parts manufactured, according to David Tweedie, general manager for advanced combat engines at GE.

In accordance with AETP requirements, the XA100 ramps up engine thrust by 10 percent while simultaneously improving fuel efficiency by 25 percent over what would typically be possible with a fighter jet engine. The key is XA100's variable cycle that allows for adjustment to the bypass ratio and fan pressure.

"Historically, the big turbofans have a much lower bypass ratio and a much higher fan pressure ratio, and that gives you very high specific thrust," Tweedie said. "For a given technology, you can either optimize for fuel efficiency or thrust depending on what you want the aircraft to do."

Traditionally, he said, militaries have lived with low fuel efficiency in fighters because range was not a major concern during combat. That has been changing in recent years, however. "What we've seen happen is, with where our adversaries are heading and the improvements in their standoff capabilities, nowadays range is a much more important part for ... fighters than has historically been the case," he said....

...Beyond the primary goal of maximizing both range and thrust, the XA100 allows for improved thermal management, which is becoming more important as more powerful aircraft systems generate more and more heat and exteriors are switched from aluminum to composite skins, which Tweedie said act like a Thermos.

According to Tweedie, the improved thermal management is accomplished through two main tactics. GE used more temperature-resistant ceramic matrix composites developed for its commercial engines and added a cool third stream that acts as a heat sink inside the engine. Most modern engines have two airstreams. Additive technology has changed the way that GE can design engines, Tweedie said....

...While the earlier Adaptive Versatile Engine Technology program was solely about scientific testing to prove out technology, AETP was based on applying that technology to an actual use case by choosing a platform with program requirements and proving that the adaptive engines could be developed under those restrictions and at a workable cost....

..."The most direct transition for this technology would be the F-35A," he said. "There's talk about spinning off the technology into upgrades for 4th-gen fighters, whether that’s F-15, F-16 or F-22 platforms, and certainly it's under considerations as we think about future platforms.”..."

Photo: "GE promotional materials showing the three air streams in the XA100 engine. (GE/AVI screenshot)" https://cdn.aviationtoday.com/wp-conten ... /xa100.png


Source: https://www.aviationtoday.com/2019/03/0 ... er-engine/

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 00:06
by sferrin
"ramps up engine thrust by 10 percent"

10% over what? GE's F136? The published F135 value of 42k? The 50k that P&W have actually run the F135 at?

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 00:15
by spazsinbad
The published value would be the number - is that the installed thrust also. Take the number from LM F-35 FAST FACTS?

Propulsion* (uninstalled thrust ratings) F135-PW-100 40,000 lb Max. 25,000 lb Mil. [why quibble? Be happy with numbers]

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 00:18
by SpudmanWP
sferrin wrote:"ramps up engine thrust by 10 percent"

10% over what?


"the XA100 ramps up engine thrust by 10 percent while simultaneously improving fuel efficiency by 25 percent over what would typically be possible with a fighter jet engine"

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 00:38
by wrightwing
spazsinbad wrote:The published value would be the number - is that the installed thrust also. Take the number from LM F-35 FAST FACTS?

Propulsion* (uninstalled thrust ratings) F135-PW-100 40,000 lb Max. 25,000 lb Mil. [why quibble? Be happy with numbers]

Most sources have it at 28k/43k.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 01:55
by spazsinbad
So cite these sources. Why does it matter so much? What can you do about it? Until the NATOPS / Dash One Flight Manuals become available then the guessing will continue if you have different numbers (installed or uninstalled?). And so it goes.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 02:49
by fbw
spazsinbad wrote:So cite these sources. Why does it matter so much? What can you do about it? Until the NATOPS / Dash One Flight Manuals become available then the guessing will continue if you have different numbers (installed or uninstalled?). And so it goes.


Doesn’t matter considering they are uninstalled sea level bench test figures. Interestingly, some Pratt datasheets list all three at 43k lbs of thrust. Others like first below list the F135-PW-600 at 41k lbs of thrust. That’s what I recall too, limitations of the lift fan and roll posts to handle more. Then it’s been 8-9 years, who knows if my recollection is accurate.

http://filecache.mediaroom.com/mr5mr_pr ... _pcard.pdf
http://filecache.mediaroom.com/mr5mr_pr ... tfacts.pdf

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 04:19
by spazsinbad
Thanks for the 20 May 2016 noise P&W F135 facts 'fbw'. The 'noise' PDF cites: "...The F135 provides a maximum thrust of 43,000 lbs. for three F-35 variants..." whilst the other cited P&W PDF dated 27 Jun 2018 says: "...Maximum thrust class (CTOL/CV) 43,000 pounds (191.3 kN) Maximum thrust class (STOVL) 41,000 pounds (182.4 kN)…" which is not quite as precise I'll guess. Doubtless other 'dates' for the F135 info may say the same - or not. Why does LM state what it does? [No need to answer except if you represent LM for publishing these details]

Again though how is this helpful when viewing these figures via a computer screen? Sure it is good to have the 'rough figure' - whatever it is (personally I'm not bothered what it is) - however did not the good 'Chip' Berke tell us not to be comparing these figures with other aircraft? The F-22/F-35 are fifth gen operating in another sphere, being figured out?

There are threads about this topic of thrust & weight of the various engines also including the aircraft variants weight(s).

LONG post about F135 upgrades: viewtopic.php?f=56&t=27458&p=293358&hilit=installed+uninstalled#p293358 Jun 2015
The F135 Block Upgrade Plan [SIX PAGE PDF of entire article "Towards Tomorrow's US Fighter Engines" attached below]
Jun 2015 AIRinternational Chris Kjelgaard

"...During its original ground-testing effort for the F135, P&W ran an unimproved engine at thrust levels of up to 51,000lb in uninstalled configuration (ie. without any accessory gearboxes or drives drawing power from the engine). This suggested that, even on an installed basis, the F135 had several thousand pounds of additional thrust available if necessary, if run at high temperatures…."

Source: https://www.scribd.com/doc/269303020/AIR-US-NG

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 13:57
by mixelflick
wrightwing wrote:
Dragon029 wrote:I wonder whether either this 20% or earlier 30% range increase figures were made in error. Either one could make sense depending on what airspeeds and altitudes the peak efficiency figures are being reached at. Even if it is 20%, that could potentially mean greater loiter capability, or it could make the F-35 able to / better at supercruising, depending on how the 3rd stream is configured and sized, what regime the fan is optimised for, etc.

I'm not sure about the phase 1 motors, but have seen figures like 20% thrust increase, 50% loiter increase, and 30 to 35% range increase, for proposed phase 2 motors.


Those are ginormous jumps in thrust, loiter and range. It's going to perform like a whole 'nother aircraft if they can even get close. Will go a long way toward tidying up the ability to super-cruise, how fast it can get from mach 1.2 to mach 1.6 (and likely beyond). And a 30-35% increase in range... perhaps the most meaningful metric, given our pivot toward the SCS.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 15:22
by sferrin
spazsinbad wrote:The published value would be the number - is that the installed thrust also. Take the number from LM F-35 FAST FACTS?

Propulsion* (uninstalled thrust ratings) F135-PW-100 40,000 lb Max. 25,000 lb Mil. [why quibble? Be happy with numbers]


Okay, so who's "facts" are better? P&W says 43k (a 7.5% difference). I don't get all the hysteria about asking a simple question. It's like a few of you feel personally attacked that anybody would wonder exactly what GE meant. :-?

Capture.PNG

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 21:24
by spazsinbad
Who has hysteria? Now we have numbers for 'class', 'installed', 'uninstalled' and 'no qualifier'. Then we have the 'test number' uninstalled at high temperatures (not used in F-35) without other equipment NOT taking power from engine. One would assume that 'uninstalled' means no equipment taking power from the engine? 'TEG' answered that somewhere here.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 22:17
by sferrin
spazsinbad wrote:Who has hysteria? Now we have numbers for 'class', 'installed', 'uninstalled' and 'no qualifier'. Then we have the 'test number' uninstalled at high temperatures (not used in F-35) without other equipment NOT taking power from engine. One would assume that 'uninstalled' means no equipment taking power from the engine? 'TEG' answered that somewhere here.


One would assume that, special circumstances aside, published values by the engine maker would be on a bench. That they're almost universally "bench" (test stand) values. So when GE claims a 10% improvement without saying over what it's a useless statement.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 22:51
by spazsinbad
sferrin wrote:
spazsinbad wrote:Who has hysteria? Now we have numbers for 'class', 'installed', 'uninstalled' and 'no qualifier'. Then we have the 'test number' uninstalled at high temperatures (not used in F-35) without other equipment NOT taking power from engine. One would assume that 'uninstalled' means no equipment taking power from the engine? 'TEG' answered that somewhere here.


One would assume that, special circumstances aside, published values by the engine maker would be on a bench. That they're almost universally "bench" (test stand) values. So when GE claims a 10% improvement without saying over what it's a useless statement.

Ten percent of whatever the thrust is? Shirley that is significant. Ten percent of anything is not bad at all. I want it now.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 30 Mar 2019, 23:07
by sferrin
Sure. But you can get a 7.5% bump just by changing your source from Lockheed Martin to Pratt & Whitney. No money or time required. :wink:

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 31 Mar 2019, 00:22
by wrightwing
If they're using P&W numbers, then it's a 10% increase from 43K (~47.3K.)

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 31 Mar 2019, 00:25
by spazsinbad
sferrin wrote:Sure. But you can get a 7.5% bump just by changing your source from Lockheed Martin to Pratt & Whitney. No money or time required. :wink:

:devil: Just run the engine hotter (like Ruskie Engyns) and your uncle is bob. :doh: No waiting for engine failure though. :roll:

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 31 Mar 2019, 14:12
by sferrin
spazsinbad wrote:
sferrin wrote:Sure. But you can get a 7.5% bump just by changing your source from Lockheed Martin to Pratt & Whitney. No money or time required. :wink:

:devil: Just run the engine hotter (like Ruskie Engyns) and your uncle is bob. :doh: No waiting for engine failure though. :roll:


Not quite what I meant. :)

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 31 Mar 2019, 18:54
by zero-one

Just thought some of you might want to see the promo ad

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 01 Apr 2019, 13:31
by mixelflick
Have to hand it to GE, great video.

One of the best facets of capitalism is competition, and the great engine war between GE and Pratt and Whitney is a fine example. Both companies have produced killer engines. Oh how the Chinese and Russians would love to get their hands on one of these. The F-35 is only going to get more capable, thanks to these advanced motors...

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 03 Apr 2019, 21:01
by steve2267
zero-one wrote:
Just thought some of you might want to see the promo ad


Except... that the bit @ 1:11, “It’s the only engine...” is patently false.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 16 Jun 2019, 02:08
by jetblast16


Fascinating video, where Vago interviews Dave Tweedie, the vice president for advanced combat engine programs at GE Aviation, about the history and future of three-stream variable-cycle turbofan engines

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 16 Jun 2019, 02:43
by quicksilver
At what thrust level does the need arise to change the inlet geometry? Just wonderin’...

Would be interesting to see the analysis of what happens to the surge margins throughout the envelope as thrust increases.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 16 Jun 2019, 05:51
by optimist
I think the inlet applies to top speed more than acceleration. The f-35 is already speed limited, so I doubt it would have much effect.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 16 Jun 2019, 18:25
by quicksilver
Mass flow. Engine has to breathe...

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 06:06
by Corsair1963
Could we see the winner of a future 6th Generation Engine Program. (XA-100 or XA-101) Going to one or both of the NGAD and/or PCA. While, the loser could upgrade the F-35??? Especially, if the loser is the XA-101? (P&W)




hmmm

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 07:02
by popcorn
jetblast16 wrote:

Fascinating video, where Vago interviews Dave Tweedie, the vice president for advanced combat engine programs at GE Aviation, about the history and future of three-stream variable-cycle turbofan engines


What engine. Is being referred to at the 7:52 mark?

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 07:30
by Dragon029
Corsair1963 wrote:Could we see the winner of a future 6th Generation Engine Program. (XA-100 or XA-101) Going to one or both of the NGAD and/or PCA. While, the loser could upgrade the F-35??? Especially, if the loser is the XA-101? (P&W)


The engine that goes into the F-35 and the engine that goes into the NGAD / PCA have been regarded as separate in past discussions. The XA100 / XA101 is currently designed more or less specifically for the F-35, while the next gen will either get the same engine (F110/F100 style on the F-15/F-16), or a variation (F119/F135 style) tailored for the NGAD / PCA (perhaps with some component commonality).

Regardless though, the winner of the AETP program is probably going to want the F-35 contract; it is a single engine fighter, but 1x 3500+ engines > 2x 500-1000 engines. The loser and winner will likely get to re-compete over the other programs as there'll be a few extra years to make improvements to reliability, cost, etc and potentially come up with something that's even better value.

popcorn wrote:What engine. Is being referred to at the 7:52 mark?


https://www.aviationtoday.com/2018/10/1 ... nbaa-2018/
https://en.wikipedia.org/wiki/General_Electric_Affinity

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 08:31
by popcorn
Dragon029 wrote:
popcorn wrote:What engine. Is being referred to at the 7:52 mark?


https://www.aviationtoday.com/2018/10/1 ... nbaa-2018/
https://en.wikipedia.org/wiki/General_Electric_Affinity


Thank you.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 10:06
by Corsair1963
Dragon029 wrote:
Corsair1963 wrote:Could we see the winner of a future 6th Generation Engine Program. (XA-100 or XA-101) Going to one or both of the NGAD and/or PCA. While, the loser could upgrade the F-35??? Especially, if the loser is the XA-101? (P&W)


The engine that goes into the F-35 and the engine that goes into the NGAD / PCA have been regarded as separate in past discussions. The XA100 / XA101 is currently designed more or less specifically for the F-35, while the next gen will either get the same engine (F110/F100 style on the F-15/F-16), or a variation (F119/F135 style) tailored for the NGAD / PCA (perhaps with some component commonality).

Regardless though, the winner of the AETP program is probably going to want the F-35 contract; it is a single engine fighter, but 1x 3500+ engines > 2x 500-1000 engines. The loser and winner will likely get to re-compete over the other programs as there'll be a few extra years to make improvements to reliability, cost, etc and potentially come up with something that's even better value.

popcorn wrote:What engine. Is being referred to at the 7:52 mark?


https://www.aviationtoday.com/2018/10/1 ... nbaa-2018/
https://en.wikipedia.org/wiki/General_Electric_Affinity



Production should be slowing down post 2035-2040 for F-35. When the PCA and NGAD come online. So, don't see the AETP Winner being as interested in the F-35 vs latter two. Unless the AETP come online far earlier???

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 10:45
by popcorn
Corsair1963 wrote:[
Production should be slowing down post 2035-2040 for F-35. When the PCA and NGAD come online. So, don't see the AETP Winner being as interested in the F-35 vs latter two. Unless the AETP come online far earlier???

The potential for new-build F-35s and the probability of swapping out thousands of F135s may present the larger opportunity.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 13:52
by fbw
Corsair1963 wrote:
Dragon029 wrote:
Corsair1963 wrote:Could we see the winner of a future 6th Generation Engine Program. (XA-100 or XA-101) Going to one or both of the NGAD and/or PCA. While, the loser could upgrade the F-35??? Especially, if the loser is the XA-101? (P&W)


The engine that goes into the F-35 and the engine that goes into the NGAD / PCA have been regarded as separate in past discussions. The XA100 / XA101 is currently designed more or less specifically for the F-35, while the next gen will either get the same engine (F110/F100 style on the F-15/F-16), or a variation (F119/F135 style) tailored for the NGAD / PCA (perhaps with some component commonality).

Regardless though, the winner of the AETP program is probably going to want the F-35 contract; it is a single engine fighter, but 1x 3500+ engines > 2x 500-1000 engines. The loser and winner will likely get to re-compete over the other programs as there'll be a few extra years to make improvements to reliability, cost, etc and potentially come up with something that's even better value.

popcorn wrote:What engine. Is being referred to at the 7:52 mark?


https://www.aviationtoday.com/2018/10/1 ... nbaa-2018/
https://en.wikipedia.org/wiki/General_Electric_Affinity



Production should be slowing down post 2035-2040 for F-35. When the PCA and NGAD come online. So, don't see the AETP Winner being as interested in the F-35 vs latter two. Unless the AETP come online far earlier???


As stated previously, there are two different phases. The above XA100 and XA101 are competing for the F-35 re-engining in the mid-2020’s, that stage of the AETP program runs till 2021, presumably they will choose to integrate one of the two after phase of the program wraps up (though P&W is pushing the F135 GO 1.0 & 2.0 to head this off). The June, 2018 contract modification suggests that an engine derivative will be developed for any “future air superiority applications” in phase 2 which runs after 2021.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 13:56
by sferrin
The first being limited to the F-35 engine-bay's physical dimensions. The follow-on is not.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 18:34
by sferrin
fbw wrote:As stated previously, there are two different phases. The above XA100 and XA101 are competing for the F-35 re-engining in the mid-2020’s, that stage of the AETP program runs till 2021, presumably they will choose to integrate one of the two after phase of the program wraps up (though P&W is pushing the F135 GO 1.0 & 2.0 to head this off).


I wonder if they could end up with BOTH, like they currently have with the F-15/-16. (F100-220 being replaced with F110-129 or F100-229.)

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 23:48
by wrightwing
Corsair1963 wrote:
Dragon029 wrote:
Corsair1963 wrote:Could we see the winner of a future 6th Generation Engine Program. (XA-100 or XA-101) Going to one or both of the NGAD and/or PCA. While, the loser could upgrade the F-35??? Especially, if the loser is the XA-101? (P&W)


The engine that goes into the F-35 and the engine that goes into the NGAD / PCA have been regarded as separate in past discussions. The XA100 / XA101 is currently designed more or less specifically for the F-35, while the next gen will either get the same engine (F110/F100 style on the F-15/F-16), or a variation (F119/F135 style) tailored for the NGAD / PCA (perhaps with some component commonality).

Regardless though, the winner of the AETP program is probably going to want the F-35 contract; it is a single engine fighter, but 1x 3500+ engines > 2x 500-1000 engines. The loser and winner will likely get to re-compete over the other programs as there'll be a few extra years to make improvements to reliability, cost, etc and potentially come up with something that's even better value.

popcorn wrote:What engine. Is being referred to at the 7:52 mark?


https://www.aviationtoday.com/2018/10/1 ... nbaa-2018/
https://en.wikipedia.org/wiki/General_Electric_Affinity



Production should be slowing down post 2035-2040 for F-35. When the PCA and NGAD come online. So, don't see the AETP Winner being as interested in the F-35 vs latter two. Unless the AETP come online far earlier???


The upgraded F-35 motors should be available in the 2020s (probably by Block 5, but maybe sooner.) Of course there's the potential for keeping older jets at a common configuration, which would mean a lot more business than just new production jets.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 17 Jun 2019, 23:58
by marauder2048
fbw wrote: The June, 2018 contract modification suggests that an engine derivative will be developed for any “future air superiority applications” in phase 2 which runs after 2021.



Or it's just the flight test portion which AETP didn't originally envision.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 18 Jun 2019, 00:41
by fbw
marauder2048 wrote:
fbw wrote: The June, 2018 contract modification suggests that an engine derivative will be developed for any “future air superiority applications” in phase 2 which runs after 2021.



Or it's just the flight test portion which AETP didn't originally envision.


Not according to GE’s general manager for the program, but clarity is lacking on several fronts in regards to future F-35 propulsion and what is going to come out of NGAD.

In an interview with FlightGlobal, Dan McCormick, GE’s general manager for the Advanced Combat Engine Programme, agrees that the AETP demonstrators are “F-35 design-centric”. The new programme awarded in June is aimed at the next generation of aircraft, he says.

In keeping with the USAF’s secretive approach to defining the next air superiority fighter, critical details of the new programme — including its work scope and name — are not released.

https://www.flightglobal.com/news/artic ... ut-450053/

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 18 Jun 2019, 01:17
by marauder2048
fbw wrote:
marauder2048 wrote:
fbw wrote: The June, 2018 contract modification suggests that an engine derivative will be developed for any “future air superiority applications” in phase 2 which runs after 2021.



Or it's just the flight test portion which AETP didn't originally envision.


Not according to GE’s general manager for the program, but clarity is lacking on several fronts in regards to future F-35 propulsion and what is going to come out of NGAD.

In an interview with FlightGlobal, Dan McCormick, GE’s general manager for the Advanced Combat Engine Programme, agrees that the AETP demonstrators are “F-35 design-centric”. The new programme awarded in June is aimed at the next generation of aircraft, he says.

In keeping with the USAF’s secretive approach to defining the next air superiority fighter, critical details of the new programme — including its work scope and name — are not released.

https://www.flightglobal.com/news/artic ... ut-450053/


New program/new effort or just Trimble putting words in that guy's mouth; the award was under the original
AETP contract.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 18 Jun 2019, 11:54
by sferrin
"While neither GE nor Pratt have released details of their adaptive-engine design, both incorporate variable geometry devices that dynamically alter the fan pressure ratio and overall bypass ratio—the two key factors influencing specific fuel consumption and thrust. The adaptive, multistage fan boosts fan pressure ratio to fighter engine performance levels during takeoff and acceleration, and in cruise lowers it to transport aircraft-like levels for improved fuel efficiency. The third stream, which is external to both the core and standard bypass duct, is used to alter the bypass ratio."

Adaptive Change

»GE and P&W defining sixth-gen fighter engine designs under Adaptive Engine Transition Program (AETP)

»USAF adopts new engine-naming convention to recognize importance of adaptive cycle

»GE developing XA100, Pratt developing XA101

»Initial engine sized at 45,000-lb.-thrust to suit F-35


»Production A100/101 derivatives targeted at F-X and F/A-XX

https://aviationweek.com/propulsion/six ... udies-ramp

"The work is being conducted under the U.S. Air Force’s Adaptive Engine Transition Program (AETP), a broadbased initiative launched in 2016 to mature variable-cycle technology for sixth-generation fighters as well as, potentially, provide a future re-engining option for the Pratt & Whitney F135-powered Lockheed Martin F-35. The program, which also leverages earlier variable-cycle testing conducted under the Air Force Research Laboratory’s Adaptive Engine Technology Development program (AETD), is initially focused on demonstrators in the 45,000-lb.-thrust range.

Even as GE works on the XA100 demonstrator and Pratt develops its virtually identically sized XA101 counterpart, both are also now working on additional clean-sheet adaptive engine concepts specifically for sixth-generation designs. Awarded as modifications to the original AETP program agreement, the contracts for this new work cover a broader application of other advanced engine technologies—including three-stream architecture—and go beyond the limiting confines of the F-35-centric XA100/101 demonstrators."

https://aviationweek.com/combat-aircraf ... ork-spools

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 24 Jun 2019, 20:56
by That_Engine_Guy
sferrin wrote:I wonder if they could end up with BOTH, like they currently have with the F-15/-16. (F100-220 being replaced with F110-129 or F100-229.)


Like all the countries lined up to replace their PW-220s with PW-229s, and their GE-100s to GE-129s? :lmao:

Besides the 'kit' to upgrade the PW-200s to PW-220, I don't think anything beyond a handful of ANG/USAF Block 42s have received NEW build engines to replace their older ones.

Hell, the USAF even ran 30 year old PW-100s in their ANG Eagles until the ANG freed up PW-220s from their Viper fleet that were 'hand-me-downed'. The USAF is talking about PW-220s being used through 2045!? Why wouldn't you replace them after 30 years with 'new' motors with newer tech. PW-220s will be almost 60 years old by 2045!

If I remember correctly, the USAF was spending more PER YEAR per engine, to overhaul/maintain the F100-PW-100s than each engine cost new in the 1970s!

Even these countries moving to "F-16V Standard" (or whatever pet program suffix/name they have) fail to spend the $5M+ per aircraft to purchase new build motors GE or PW. They still run their PW-220s or GE-100s. It seems they're not interested spending THAT much $$ for the additional power, lower fuel burn, or reduced maintenance costs.

Just sayin'....

Keep 'em flyin' :thumb:
TEG

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 24 Jun 2019, 21:25
by marauder2048
sferrin wrote:
»GE and P&W defining sixth-gen fighter engine designs under Adaptive Engine Transition Program (AETP)

»USAF adopts new engine-naming convention to recognize importance of adaptive cycle

»GE developing XA100, Pratt developing XA101

»Initial engine sized at 45,000-lb.-thrust to suit F-35


»Production A100/101 derivatives targeted at F-X and F/A-XX


Naturally, you'd build production derivatives for airframes that don't exist.


sferrin wrote:the contracts for this new work cover a broader application of other advanced engine technologies—including three-stream architecture—and go beyond the limiting confines of the F-35-centric XA100/101 demonstrators."


Limiting confines..for what I think is the largest turbofan installed on any production fighter.
Unless they are arguing that the DSI capture area isn't adequate.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 25 Jun 2019, 01:08
by sferrin
That_Engine_Guy wrote:
sferrin wrote:I wonder if they could end up with BOTH, like they currently have with the F-15/-16. (F100-220 being replaced with F110-129 or F100-229.)


Like all the countries lined up to replace their PW-220s with PW-229s, and their GE-100s to GE-129s? :lmao:
TEG


You'll note there are both -229s and -129s available if somebody wants them. That's all I'm suggesting.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 25 Jun 2019, 01:10
by sferrin
marauder2048 wrote:
sferrin wrote:
»GE and P&W defining sixth-gen fighter engine designs under Adaptive Engine Transition Program (AETP)

»USAF adopts new engine-naming convention to recognize importance of adaptive cycle

»GE developing XA100, Pratt developing XA101

»Initial engine sized at 45,000-lb.-thrust to suit F-35


»Production A100/101 derivatives targeted at F-X and F/A-XX


Naturally, you'd build production derivatives for airframes that don't exist.


sferrin wrote:the contracts for this new work cover a broader application of other advanced engine technologies—including three-stream architecture—and go beyond the limiting confines of the F-35-centric XA100/101 demonstrators."


Limiting confines..for what I think is the largest turbofan installed on any production fighter.
Unless they are arguing that the DSI capture area isn't adequate.


Not sure what your point is here. I was pointing out that the initial effort will be restricted by the F135 physical envelope. The follow-on derivatives would not be. (And yes, the follow on derivatives would be larger and more powerful.)

TLDR: Initial effort can't be bigger than the F135 else it won't fit. The follow-on doesn't have that restriction.

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 25 Jun 2019, 02:02
by marauder2048
IIRC, even largest variable cycle engines considered for ESAV or LRSA (200 klbs+ TOGW) were smaller than F135.

Part of the appeal of say a tailless aircraft is a reduction in the thrust requirement from the engine(s).

Re: GE Aviation’s future fighter engine TECHNOLOGY XA100

Unread postPosted: 25 Jun 2019, 03:01
by sferrin
marauder2048 wrote:IIRC, even largest variable cycle engines considered for ESAV or LRSA (200 klbs+ TOGW) were smaller than F135.

Part of the appeal of say a tailless aircraft is a reduction in the thrust requirement from the engine(s).


This would require a bigger engine than the F-35:

index.jpg


Also, the language used in the article isn't clear as to whether the variant for the F-35 would have a 3rd stream. Regardless, this (and other) articles are pretty clear - the follow on variants will be larger and more powerful than those for the F-35.