GE XA100 and P&W XA101 AETP engines

It's an astonishing decision, indeed. AETP was discussed as being upgradable onto the F-35 since its inception.
Although we can understand that the acceleration of NGAD had an impact on its availability for other platforms, a cancelation leaves the F-35 with a single engine supplier for the duration of the program... Probably 50 years. That amount of exclusivity will have an impact on the industry. We have to wonder how decision makers are planning to balance that.

The winners are probably RR and, perhaps, Safran. They now have de-facto an avenue to augment their manufacturing numbers and decrease the astronomical price of their very segmented original host platforms.
The winner is P&W, who can now say "Sure our reliability is well below targets, but our current motor won't hit the performance or cooling requirements for future blocks so now you have no choice but to sole source our upgrade path."
 
Very disappointing. We will regret this.
I feel like for US military if anything seem even a little bit innovative, they are often cancelled in favor of the old/traditional things.
the same thing happened before with
YF-23, NGM (JDRADM) , LRASM-B , Ramjet Harm, ramjet AIM-120 and now XA100
 
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Very disappointing. We will regret this.
I feel like for US military if anything seem even a little bit innovative, they are often cancelled in favor of the old/traditional things.
the same thing happened before with
YF-23, NGM (JDRADM) , LRASM-B , Ramjet Harm, ramjet AIM-120 and now XA100
To be fair, new tech has risks, and the military is not eager to shell out cash to fix up their newfangled gadgets in case they have issues.
 
Very disappointing. We will regret this.
I feel like for US military if anything seem even a little bit innovative, they are often cancelled in favor of the old/traditional things.
the same thing happened before with
YF-23, NGM (JDRADM) , LRASM-B , Ramjet Harm, ramjet AIM-120 and now XA100
To be fair, new tech has risks, and the military is not eager to shell out cash to fix up their newfangled gadgets in case they have issues.
I get your point, but I feel like more often than not, they will spend load of money on new tech, get it nearly work or even a working prototype, then cancel it, then came back do the samething again with that same tech, over and over. Then the adversary get the lead on the tech which they developed first. Take for example, ramjet cruise missile and hypersonic weapons.
 
Very disappointing. We will regret this.
I feel like for US military if anything seem even a little bit innovative, they are often cancelled in favor of the old/traditional things.
the same thing happened before with
YF-23, NGM (JDRADM) , LRASM-B , Ramjet Harm, ramjet AIM-120 and now XA100
To be fair, new tech has risks, and the military is not eager to shell out cash to fix up their newfangled gadgets in case they have issues.
I get your point, but I feel like more often than not, they will spend load of money on new tech, get it nearly work or even a working prototype, then cancel it, then came back do the samething again with that same tech, over and over. Then the adversary get the lead on the tech which they developed first. Take for example, ramjet cruise missile and hypersonic weapons.
True, so very much true.
 
Very disappointing. We will regret this.
I feel like for US military if anything seem even a little bit innovative, they are often cancelled in favor of the old/traditional things.
the same thing happened before with
YF-23, NGM (JDRADM) , LRASM-B , Ramjet Harm, ramjet AIM-120 and now XA100
The YF-23 was not cancelled. It was built and was not competitively down-selected. JDRADM gave way to AIM-260 with the AF secretly moving towards that direction around the same time the T3 program matured or completed. Ramjet AIM-120 was not a requirement. Ramjet HARM likewise gave way to HARM upgrade and now ultimately to the SiAW program. Adaptive engine development investments will only increase over time funded via the NGAD and NGAP efforts. They just awarded rather large propulsion integration contracts just months ago.
 
Pure speculation on my part but could the existing engines have the potential to be upgraded to within 90+% of the new engines making replacement more costly than the additional capabilities warrant?
 
Pure speculation on my part but could the existing engines have the potential to be upgraded to within 90+% of the new engines making replacement more costly than the additional capabilities warrant?
Not that Pratt, USAF, or LM has indicated. The EEP upgrades would increase thrust, range, and thermal management at most about half as much as an ATEP turbine, compared to the existing baseline. That's going off Pratt and Air Force statements, GE has been claiming there's an even larger gap.
 
It's an astonishing decision, indeed. AETP was discussed as being upgradable onto the F-35 since its inception.
Although we can understand that the acceleration of NGAD had an impact on its availability for other platforms, a cancelation leaves the F-35 with a single engine supplier for the duration of the program... Probably 50 years. That amount of exclusivity will have an impact on the industry. We have to wonder how decision makers are planning to balance that.

The winners are probably RR and, perhaps, Safran. They now have de-facto an avenue to augment their manufacturing numbers and decrease the astronomical price of their very segmented original host platforms.
The winner is P&W, who can now say "Sure our reliability is well below targets, but our current motor won't hit the performance or cooling requirements for future blocks so now you have no choice but to sole source our upgrade path."
F135 is the most reliable engine ever in a single engine fighter.

Durability of the high pressure turbine, running with the highest turbine inlet temperatures ever in a production engine, has been less than desired when exposed to the Middle East high calcium / low melting point sand environment. But improved turbine blades are already in production and being installed during shop visits to address that problem. Even when running the engine well beyond its bleed air specification in the current aircraft blocks.

The enhanced core incorporates technology from the Navy funded fuel burn reduction program to significantly improve the high compressor efficiency, lowering TIT and improving SFC while providing improved cooling capacity and performance margin. All while being easily incorporated into the depot overhaul process with little change to the overall support system or aircraft integration.

The three stream technologies demonstrated in the XA100 and XA101 will continue to be developed and will be introduced in future aircraft, you can be certain.
 
It's an astonishing decision, indeed. AETP was discussed as being upgradable onto the F-35 since its inception.
Although we can understand that the acceleration of NGAD had an impact on its availability for other platforms, a cancelation leaves the F-35 with a single engine supplier for the duration of the program... Probably 50 years. That amount of exclusivity will have an impact on the industry. We have to wonder how decision makers are planning to balance that.

The winners are probably RR and, perhaps, Safran. They now have de-facto an avenue to augment their manufacturing numbers and decrease the astronomical price of their very segmented original host platforms.
The winner is P&W, who can now say "Sure our reliability is well below targets, but our current motor won't hit the performance or cooling requirements for future blocks so now you have no choice but to sole source our upgrade path."
F135 is the most reliable engine ever in a single engine fighter.

Durability of the high pressure turbine, running with the highest turbine inlet temperatures ever in a production engine, has been less than desired when exposed to the Middle East high calcium / low melting point sand environment. But improved turbine blades are already in production and being installed during shop visits to address that problem. Even when running the engine well beyond its bleed air specification in the current aircraft blocks.

The enhanced core incorporates technology from the Navy funded fuel burn reduction program to significantly improve the high compressor efficiency, lowering TIT and improving SFC while providing improved cooling capacity and performance margin. All while being easily incorporated into the depot overhaul process with little change to the overall support system or aircraft integration.

The three stream technologies demonstrated in the XA100 and XA101 will continue to be developed and will be introduced in future aircraft, you can be certain.
I realize at some point I'm arguing the best thing since sliced bread isn't best enough, an I'm not trying to argue 135 is crap. However, the DoD and industry have a real opportunity to both give the F-35 family a serious step up in capability and retire risks for NGAP. However well EEP goes, we may regret passing those up a lot more than we regret spending the money.
 
However, the DoD and industry have a real opportunity to both give the F-35 family a serious step up in capability and retire risks for NGAP. However well EEP goes, we may regret passing those up a lot more than we regret spending the money.

The current FoM program is expected to cost about $15 Bn. Given that level of commitment and the sheer depth of capability that is being upgraded, I doubt anyone can say that they aren't treating F-35 modernization seriously. NGAP continues from AETP and has already started (contracts for it were exercised a couple of years ago) so in a way it already had a head start compared to a hypothetical F-35 adaptive engine EMD program based on the two adaptive engine tech demonstrators.
 
Let's just hope that it succeeds!
This is the "if you give us the money, we'll do it" pitch the Navy has tried a few times lately. When it comes to ordering an additional ship, Congress has shown some willingness. But I don't think Congress will do it unless they can get the Navy to admit they're interested, or OSD weighs in favorably.
 
Don't know if this has been posted already:
 
Let's just hope that it succeeds!
This is the "if you give us the money, we'll do it" pitch the Navy has tried a few times lately. When it comes to ordering an additional ship, Congress has shown some willingness. But I don't think Congress will do it unless they can get the Navy to admit they're interested, or OSD weighs in favorably.
Looks like the USAF might be getting that money after all

 
Let's just hope that it succeeds!
This is the "if you give us the money, we'll do it" pitch the Navy has tried a few times lately. When it comes to ordering an additional ship, Congress has shown some willingness. But I don't think Congress will do it unless they can get the Navy to admit they're interested, or OSD weighs in favorably.
Looks like the USAF might be getting that money after all

As I understand it, the increased funding is mainly for ICBM and the next generation fighter, nothing for XA100 though
 
As I understand it, the increased funding is mainly for ICBM and the next generation fighter, nothing for XA100 though
NGAP has a mention though:

To power NGAD, the service will also continue developing the fighter’s Next Generation Adaptive Propulsion (NGAP) engine, seeking $595 million in the coming fiscal year. RDT&E spending will finish off in FY27 at a level of $291 million, according the the j-books, which state that “competitive prototyping” work would proceed between FY25 and FY28. Both Pratt & Whitney and General Electric are participating in NGAP, which a top official suggested last year could move to down-select as soon as this year.

Though with the recent news that the USAF will prioritize the improvements of the F135 engines over any Adaptive or Variable Engine developments, this may be put on hold.
 
PW saying the AETP would cost $40 billion more than their F135 engine looks to me like trying to poison the well and kill the program because they think GE will win. And on fit and schedule, GE should win. Which would give GE the inside track on the engine for NGAD as well, and leave PW with nothing.
 
As I understand it, the increased funding is mainly for ICBM and the next generation fighter, nothing for XA100 though
NGAP has a mention though:

To power NGAD, the service will also continue developing the fighter’s Next Generation Adaptive Propulsion (NGAP) engine, seeking $595 million in the coming fiscal year. RDT&E spending will finish off in FY27 at a level of $291 million, according the the j-books, which state that “competitive prototyping” work would proceed between FY25 and FY28. Both Pratt & Whitney and General Electric are participating in NGAP, which a top official suggested last year could move to down-select as soon as this year.

Though with the recent news that the USAF will prioritize the improvements of the F135 engines over any Adaptive or Variable Engine developments, this may be put on hold.
NGAD always intended to have 3 stream engines through NGAP program though. It just ashamed that F-35 won't get XA100, it is rather interior to other 5 generation fighters in term of kinematic
 
Very disappointing. We will regret this.
I feel like for US military if anything seem even a little bit innovative, they are often cancelled in favor of the old/traditional things.
the same thing happened before with
YF-23, NGM (JDRADM) , LRASM-B , Ramjet Harm, ramjet AIM-120 and now XA100
The YF-23 was not cancelled. It was built and was not competitively down-selected. JDRADM gave way to AIM-260 with the AF secretly moving towards that direction around the same time the T3 program matured or completed. Ramjet AIM-120 was not a requirement. Ramjet HARM likewise gave way to HARM upgrade and now ultimately to the SiAW program. Adaptive engine development investments will only increase over time funded via the NGAD and NGAP efforts. They just awarded rather large propulsion integration contracts just months ago.
I meant the innovative option often lose out to traditional one
YF-23 is short of more unconventional compared to YF-22
Ramjet HARM is more unconventional compared to HARM with bigger motor
LRASM-B is more unconventional compared to LRASM-A (since US doesn't currently have any operational ramjet missile)
I don't think AIM-260 will go the same route as JDRADM (NGM) though, as far as we currently know, it is purely a long range air to air missile. It would be cool if it can per form air to ground role as well since F-35 weapon bay load is quite limited, but it think it is unlikely
 
PW saying the AETP would cost $40 billion more than their F135 engine looks to me like trying to poison the well and kill the program because they think GE will win. And on fit and schedule, GE should win. Which would give GE the inside track on the engine for NGAD as well, and leave PW with nothing.
And why do you think GE XA100 ahead of the P&W XA101 besides GE’s press releases? From what I’ve read, both AETP engine demonstrated the anticipated performance gains that the program was designed for. The only real advantage that you can point too is that GE finished testing first, which is likely due to the government facility availability schedule at AEDC Tullahoma.
 
PW saying the AETP would cost $40 billion more than their F135 engine looks to me like trying to poison the well and kill the program because they think GE will win. And on fit and schedule, GE should win. Which would give GE the inside track on the engine for NGAD as well, and leave PW with nothing.
And why do you think GE XA100 ahead of the P&W XA101 besides GE’s press releases? From what I’ve read, both AETP engine demonstrated the anticipated performance gains that the program was designed for. The only real advantage that you can point too is that GE finished testing first, which is likely due to the government facility availability schedule at AEDC Tullahoma.
But it doesn't sound like EITHER of them are moving forward. Instead it looks like they're simply going with the improved F135.
 
PW saying the AETP would cost $40 billion more than their F135 engine looks to me like trying to poison the well and kill the program because they think GE will win. And on fit and schedule, GE should win. Which would give GE the inside track on the engine for NGAD as well, and leave PW with nothing.
And why do you think GE XA100 ahead of the P&W XA101 besides GE’s press releases? From what I’ve read, both AETP engine demonstrated the anticipated performance gains that the program was designed for. The only real advantage that you can point too is that GE finished testing first, which is likely due to the government facility availability schedule at AEDC Tullahoma.
But it doesn't sound like EITHER of them are moving forward. Instead it looks like they're simply going with the improved F135.
Correct now for the F-35. I was referring to Apparion13’s statement that GE should have won the AETP for F-35 and is ahead for the NGAD engine competition (I.e statement in quotes)
 
And why do you think GE XA100 ahead of the P&W XA101 besides GE’s press releases? From what I’ve read, both AETP engine demonstrated the anticipated performance gains that the program was designed for. The only real advantage that you can point too is that GE finished testing first, which is likely due to the government facility availability schedule at AEDC Tullahoma.
Schedule and performance, just a general impression from various things I've read. Plus continuing issues with the F135 may have soured opinion on Pratt.

Fit, from what both have said. PW says C is doable but not simple, and B is out. GE says C is no problem, and B is doable. This is the main selling point, GE can address the entire fleet.
But it doesn't sound like EITHER of them are moving forward. Instead it looks like they're simply going with the improved F135.
Which is what I think/suspect Pratt wants. Better they continue with the F135 than lose the contract to GE.

This isn't an open and shut case. I'm not saying this is absolutely what is going on.

My impression was GE had the lead.

My suspicions were been raised by Pratt saying AETP would cost $40b more than continuing with the F135. "It will cost more" is a really unusual statement to come from a contractor, and it implies it would be better to cancel the project.

It makes it appear as if they don't want the contract. But if they pull out of the competition, they lose the F135 contract, production, and income. If they want the income, but want to pull out of the project or, as I suspect, have heard scuttlebutt that GE has the inside track, undermining the program is the only way to guarantee they keep their income.

Which results in a raised eyebrow and "yeah, that looks a bit dodgy" from me. And if I were in Congress, I'd be having it investigated just to clear up the suspicion.

Suspicious, not proven. But worth looking into. Especially given how useful the range gains would be in the Pacific, which I think makes the AETP program militarily compelling.
 
EMD development of the XA100 for the F-35A and C models will definitely cost and probably take longer more than the F135 Core Upgrade, and the path to F-35B integration is uncertain and expensive at best. Plus you need to build a whole new support system for the A100 and run it in parallel with the existing F135 infrastructure. $40B in additional cost over the lifetime of the program is not an unreasonable estimate.

P&W of course has a vested interest in keeping the F135 as the only engine for the F-35 fleet. But the Core Upgrade gives the program everything they need, plus a large portion of what they would like to have, for a fraction of the cost.

GE has nothing currently going forward toward production in military propulsion, so of course they are beating the drums for the XA100 to attempt to influence public, legislative, and military opinion.
 
GE has nothing currently going forward toward production in military propulsion, so of course they are beating the drums for the XA100 to attempt to influence public, legislative, and military opinion.
They have T901, which beat Pratt's T900, admittedly not the same animal nor the smoothest program running. But chiding GE for campaigning for their engine seems a bit pointless, P&W put a lot of effort into smothering F120 and F136 in their cribs and that's just how it goes.
 
Making the case for the new engine on operational logistical and environmental grounds.

I will leave it to smarter people to see if he is convincing.
Remember that the AETP can have 25% reduction in fuel flow and 15% increase in thrust, but not at the same time. It is likely that fuel consumption is actually higher than the F135 in the low bypass high thrust setting that is likely to be used during actual combat.

Cruise to the combat theater could be greatly improved, but total range improvement is likely to be less than the advertised 30%

And do we think peacetime fuel consumption will be less? My guess is that F-35 pilots will be using most of their 18000 lbs of fuel on each sortie, just because they can. The sortie duration may be longer, but the fuel will be burned.
 

WASHINGTON — For years, Rep. Rob Wittman, R-Va,. was known as a leading voice on naval matters in Congress. But with the 118th Congress, Wittman has left his ship committee behind and taken on the role of chairman on the House Armed Services Committee’s tactical air and land forces subcommittee.

Following a subcommittee hearing on March 29, Breaking Defense sat down with Wittman to discuss his key priorities for the Air Force.

The transcript has been edited for length and clarity.

Breaking Defense: At the hearing, you made clear you wanted everyone involved in the F-35 engine decision to provide more information before coming to your own conclusion about next steps. So what information have you received, what are you still hoping to find out, and when do you think you’ll receive enough information to make a decision?

Rep. Wittman: As we heard yesterday in the hearing, [the Government Accountability Office’s] perspective is that the BCA, the business case analysis, was more of a comparative analysis… And it revolves around, you know, if the BCA is about the ability for the engine to provide power, and to cool itself to assure engine life, how did those requirements get expressed to [Pratt & Whitney and General Electric]? What is happening on the actual engine design itself? What are the differences in not only the immediate cost, but the long-term cost of the engine, when you’re essentially upgrading the engine core, which is the compressor, how fuel is fed in there.

And then at some point, as the power demand goes up, your fuel thermal management system has to change, your power thermal management system has to change. And at some point for both engines, you have to do that, because the demands on the engines get to where the heat that you’re trying to dissipate to extend engine life starts to transfer into the other external systems on the engine…and then, too, to look at the full scope of how costs are assessed. So it’s not just the initial purchase cost of the engine, but it’s what would be the the cost over the lifetime of the aircraft, fuel consumption, the necessity for tanking aircraft, all those sorts of things are part of what you can make an argument to say you have to look at the full picture on cost. Those are things that weren’t purposely left out. But this was just an analysis about the cost initially of both engines.

The argument that’s been laid out has been that the [Engine Core Upgrade, or ECU] approach provides acceptable levels of enhanced performance while maintaining commonality across the fleet at a lower cost. Is that an argument that’s compelling to you, especially when weighed against the greater capabilities that can be gained by an adaptive engine?

Well, I think you have to dig even a little bit deeper than that. They are correct ECU is the only engine form that is able to be compatible with all three versions of the aircraft. But when you do get above a certain cooling and power demand, then you do have to make modifications to the fuel thermal management system and the power thermal management system, so those are additional requirements that would have to be done on the aircraft, regardless probably for both engine variants… There are differences in what [an adaptive] engine can do in channeling bleed air and being able to manage fuel consumption, but also manage how the engine responds to power and cooling demands. It’s a modernized engine, it’s certainly something that I think has utility for the Air Force, it’s certainly something that we are well ahead – good news, we’re well ahead of our competitors like China on that.

But the question is, what overall is the best decision? And how do you look at all the different aspects? And I think everybody needs to be aware of is, is this a decision where you say, well, we put [an adaptive engine] just in the [F-35A] and then ECU in the other versions, because that’s almost where it would take you if you did decide to somehow incorporate [an adaptive engine]. So I think that’s something that every member is going to have to ask themselves, because I can tell you, this is going to get re-litigated in the committee and on the floor. And I just want to make sure people have the full scope of information to make the decision.

You know, I’d like for it not to be parochial. And I admire and respect both companies. We need both companies in the engine manufacturing business… The question right now, though, before us is what’s the best decision going forward for the F-35. And I think there’s still more information that the [F-35 Joint Program Office, or JPO] needs to give to us.

What do you think would have to emerge for there to be appetite in Congress to move forward with an adaptive engine and essentially veto the Pentagon’s preferred approach?

I think it’s hard to tell right now, because I think there are a lot of different things that will enter into it. I think folks from those regions, obviously have an interest in the viability of the companies in their regions. That’s a legitimate concern. The larger context, though, is what’s the best long-term decision for the military and all these different variants.

Another thing too that doesn’t get mentioned — and I think needs to be part of it, not the primary part of it — we do have international partners that are going to be affected by this. So if you go down a path where all of a sudden your partners go, ‘We can’t afford that,’ the question then becomes, what do you do to make sure that their aircraft continue to be viable and that they meet their expected service life. It’s a pretty hefty price tag on that aircraft. We want to make sure that if we’re going to have them as partners that they don’t get in a situation where they look at it and go, Wow, we expected this aircraft to last a lot longer, or that the lifecycle costs were not what we projected them to be. So I think all of those things are part of the decision that will take place going forward.

There is a monetary element of that. Listen, this is not going to be like the last two years, where we’ve been able to just kind of move the top line and then arrive at that place and everybody was happy. There’s going to be a cap on where we go. And essentially, that’s where things are being worked from now. So if you are going to fund this, you’re going to have to find a bill payer… If [the Air Force has] to put more money in somewhere else, the question is, where will that come from? More than likely, it’s going to come from some sort of future capability, which is what we’ve seen in all the divest-to-invest strategy.

So I don’t know — if somebody is going to say “I’m proposing to do [the Adaptive Engine Transition Program, or AETP] for all variants, or even just for the Air Force variant,” there’s got to be a bill payer. And you can draw it from anything that you want. But that’s a domino effect. So if you draw it from here, all of a sudden, people go no, no, you can’t do that. So it’s kind of a house of cards with that.

Whoever puts an amendment in to change the JPO decision — it may be ratifying the JPO decision, it may be reversing the JPO decision, and there could be just a debate back and forth between the two. But if you’re going to go in the direction of AETP, which will take more money, you’ve got to find a bill payer, because you’re not gonna be able to just say well, we’ll add it to the top line.
 
Article is now unlocked:
The new designation indicates the NGAD engine will be a fundamentally different engine than GE’s 45,000.-lb.-thrust XA100, but both systems will share technologies.
“NGAD is not going to be a start-from-scratch, brand-new engine,” said David Tweedie, GE’s general manager for advanced products, speaking to reporters during a factory tour here on May 2.
Oh well.. it'll be an XA-100 derivative then. We'll have to wait and see what P&W brings to the table.
 
Oh well.. it'll be an XA-100 derivative then. We'll have to wait and see what P&W brings to the table.
NGAP contracts were built in as options into the AETP program itself so it was always expected that one or more programs would be born out of the overall adaptive engine funding stream at some point. These options were exercised a few years ago and both P&W and GE have been pursuing these new designs ever since.
 
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Lockheed has come out in favor of AETP for F-35 and Pratt is, shall we say, livid
Sounds like they've decided against dealing with a future of constantly trying to "make it work while being screamed at by the customer".

Honestly, Pratty has an AETP engine as well so the fact they'll complaining so much sounds like they either don't have confidence in their engine or they're just trying to hobble GE by keeping them out of the F-35 market (and learning from it for the NGAD engine). In either case it sounds like a reason FOR jumping to the 3-stream engine.
 
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Honestly, Pratty has an AETP engine as well so the fact they'll complaining so much sounds like they either don't have confidence in their engine or they're just trying to hobble GE by keeping them out of the F-35 market (and learning from it for the NGAD engine). In either case it sounds like a reason FOR jumping to the 3-stream engine.
They know that if the "upgrade current engine" path is chosen, they will 100% definitely win. Even if they were very confident in their AETP engine and thought that with it they'd have a 80% chance of winning, the smart financial move might be to lobby for the current engine.
 

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