F135 upgrades, reengining considered in new F-35 propulsion

All about the Pratt & Whitney F135 and the (cancelled) General Electric/Rolls-Royce F136
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Unread post10 Aug 2022, 02:44

steve2267 wrote:
Perhaps I should back up. I may be on a separate page than you.

Please tell -- just what is P&W strategy? And how do you know this?

Are you arguing this strategy is bad for Raytheon Technologies shareholders? Or merely stating that you personally do not like this strategy?

As best I can recall, everytime you write about the subject of AETP / ACE, you appear to dismiss the XA101 out of hand, and assume the XA100 will win. Is this your opinion? On what do you base it? GE fanboyism? Insider knowledge of test results from the two competing manufacturers? Number of press releases by the manufacturers? Number of news stories about the different manufacturers products, or developmental test articles?

GE may very well have the inside track, i.e. better technology, on the AETP program. If so, and they win the ACE competition, great, congratulations to GE and P&W will be forced to up their game again. But I have seen no competently written article by the so called aerospace press that suggests GE is ahead in the AETP / ACE competition. I've seen more press releases by GE. And more yay-rah-rah "news" articles about XA100. And I see a manufacturer who has lost the last two major fighter engine competitions fighting to get back into the business.


The P&W Strategy is very obvious to all. As they have been pushing the enhanced version of the F135 at the expense of the XA101.....

Hell, we hear virtually nothing about the latter. While, the GE XA100 is in the news almost daily. :shock:
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Unread post12 Aug 2022, 19:54

Another look at the questions at same source below 12 Aug 2022: https://breakingdefense.com/2022/08/adv ... -official/
Air Force Looks Beyond AETP for Engines to Power NGAD Fighter
11 Aug 2022 Greg Hadley

"DAYTON, Ohio—The Air Force’s Adaptive Engine Transition Program is demonstrating and maturing key technologies, but it won’t produce the engines that power the service’s Next Generation Air Dominance (NGAD) fighter, a key acquisition official said Aug. 11.

That engine will come from the lesser-known Next Generation Adaptive Propulsion program, which is still in its preliminary stages, John Sneden, director of the Air Force Life Cycle Management Center’s propulsion directorate, told reporters at the Life Cycle Industry Days conference....

...AETP
So where does that leave the two engines built as part of the Adaptive Engine Transition Program—GE’s XA100 and Pratt & Whitney’s XA101? According to Sneden, that’s a question that will be answered by the Office of the Secretary of Defense when it decides whether it wants to pursue putting AETP engines on the F-35.

Such a question has been hotly debated in Congress, within the Pentagon, and among industry as of late—GE is pushing for the XA100 engine to be put on the F-35A and F-35C, while Pratt & Whitney, which makes the F-35’s current F135 engine, has argued that the service should instead opt for a smaller “block upgrade” it is calling the F135 Enhanced Engine Package.

Part of Pratt & Whitney’s argument has been that the AETP engines were not designed to fit on the short-take-off-and-vertical-landing F-35B, and the Joint Program Office has stated that any partner in the program that wants to make its own modifications has to bear that cost alone. All the same, Sneden argued that the cost would be justified by the increased performance.

“You can optimize for performance, or you can optimize for tri-variant commonality,” Sneden said. “We think the warfighter deserves the performance attributes that AETP can deliver.”

That increased performance would take the form of 25 percent increased fuel efficiency, 10 percent more thrust, and 100 percent better thermal management, Sneden said. GE officials have cited those same figures in arguing for the XA100, but Sneden clarified that those totals could also be achieved with Pratt & Whitney’s XA101.

Should OSD decide to proceed with putting the AETP engines on the F-35, the Air Force Life Cycle Management Center would be ready to move the program into a engineering and manufacturing development phase by 2024 that would “likely be five to six years” and include flight testing, Sneden said. All told, the engine could start being put on F-35s by the end of the decade.

Should Pentagon leaders decide to stick with the F135, however, the AETP engines’ future would be uncertain at best.

The program was “built around the requirements for the F-35,” Sneden said. “So it’s not something that we kind of ported over and said, ‘Oh, you know, we could potentially go use this for F-35. It was actually developed specifically for the F-35.”

That stands in contrast to previous indications from the Air Force that the AETP engines would be the ones to power the future NGAD fighter. Now, Sneden said, the advanced propulsion industrial base faces a pivotal moment: If AETP doesn’t result in an engine going into production and only one engine is selected for the NGAP program in 2024, competition will dry up, he argued.

“If we end up with one vendor there and we don’t move forward with AETP, that vendor could actually get us into a place where we have essentially a reduced advanced propulsion industrial base,” Sneden said. “So we are concerned about it.”"

Source: https://www.airforcemag.com/air-force-l ... d-fighter/
A4G Skyhawk: www.faaaa.asn.au/spazsinbad-a4g/ & www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/videos?view_as=subscriber
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Unread post13 Aug 2022, 00:23

spazsinbad wrote:Another look at the questions at same source below 12 Aug 2022: https://breakingdefense.com/2022/08/adv ... -official/
Air Force Looks Beyond AETP for Engines to Power NGAD Fighter
11 Aug 2022 Greg Hadley

"DAYTON, Ohio—The Air Force’s Adaptive Engine Transition Program is demonstrating and maturing key technologies, but it won’t produce the engines that power the service’s Next Generation Air Dominance (NGAD) fighter, a key acquisition official said Aug. 11.

That engine will come from the lesser-known Next Generation Adaptive Propulsion program, which is still in its preliminary stages, John Sneden, director of the Air Force Life Cycle Management Center’s propulsion directorate, told reporters at the Life Cycle Industry Days conference....

...AETP
So where does that leave the two engines built as part of the Adaptive Engine Transition Program—GE’s XA100 and Pratt & Whitney’s XA101? According to Sneden, that’s a question that will be answered by the Office of the Secretary of Defense when it decides whether it wants to pursue putting AETP engines on the F-35.

Such a question has been hotly debated in Congress, within the Pentagon, and among industry as of late—GE is pushing for the XA100 engine to be put on the F-35A and F-35C, while Pratt & Whitney, which makes the F-35’s current F135 engine, has argued that the service should instead opt for a smaller “block upgrade” it is calling the F135 Enhanced Engine Package.

Part of Pratt & Whitney’s argument has been that the AETP engines were not designed to fit on the short-take-off-and-vertical-landing F-35B, and the Joint Program Office has stated that any partner in the program that wants to make its own modifications has to bear that cost alone. All the same, Sneden argued that the cost would be justified by the increased performance.

“You can optimize for performance, or you can optimize for tri-variant commonality,” Sneden said. “We think the warfighter deserves the performance attributes that AETP can deliver.”

That increased performance would take the form of 25 percent increased fuel efficiency, 10 percent more thrust, and 100 percent better thermal management, Sneden said. GE officials have cited those same figures in arguing for the XA100, but Sneden clarified that those totals could also be achieved with Pratt & Whitney’s XA101.

Should OSD decide to proceed with putting the AETP engines on the F-35, the Air Force Life Cycle Management Center would be ready to move the program into a engineering and manufacturing development phase by 2024 that would “likely be five to six years” and include flight testing, Sneden said. All told, the engine could start being put on F-35s by the end of the decade.

Should Pentagon leaders decide to stick with the F135, however, the AETP engines’ future would be uncertain at best.

The program was “built around the requirements for the F-35,” Sneden said. “So it’s not something that we kind of ported over and said, ‘Oh, you know, we could potentially go use this for F-35. It was actually developed specifically for the F-35.”

That stands in contrast to previous indications from the Air Force that the AETP engines would be the ones to power the future NGAD fighter. Now, Sneden said, the advanced propulsion industrial base faces a pivotal moment: If AETP doesn’t result in an engine going into production and only one engine is selected for the NGAP program in 2024, competition will dry up, he argued.

“If we end up with one vendor there and we don’t move forward with AETP, that vendor could actually get us into a place where we have essentially a reduced advanced propulsion industrial base,” Sneden said. “So we are concerned about it.”"

Source: https://www.airforcemag.com/air-force-l ... d-fighter/


RDEs



DARPA recently successfully tested this engine design in a rocket/missile.
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Unread post14 Aug 2022, 23:56

Very confused.....If, the XA100/XA101 are maturing nicely and offering such good performance gains over the existing F119/F135. Why would the USAF start all over and design another engine? Plus, could such an engine even be ready in time for the NGAD???


Also, with the name of "Next Generation Adaptive Propulsion Program". Then maybe its just a development of the XA100/XA101 Adaptive Cycle Engines of today?
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Unread post15 Aug 2022, 00:00

Why would the US Military even consider an Adaptive Cycle Engine (XA100 or XA101) for the F-35. If, the NGAD isn't going to get it.....


Honestly, doesn't make sense at all..... :?
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Unread post15 Aug 2022, 02:28

Advanced aircraft engine industrial base could ‘collapse’ if tech doesn’t transition: USAF official

“The perception I think that's out there is that we're maintaining, if not advancing, our military advantage in propulsion," said John Sneden, director of the Air Force's propulsion directorate. “But the reality is ... we're essentially stagnating, and we're starting to lose.”

By Valerie Insinna on August 12, 2022 at 10:35 AM

DAYTON, Ohio — The US military’s industrial base for advanced fighter engines could be on the verge of “collapse” if the Air Force decides to not pursue a new adaptive engine for the F-35, an Air Force official said on Thursday.

Currently, the Air Force is deliberating whether to move forward into the next phase of the Adaptive Engine Transition Program (AETP), which would produce a new engine for the F-35 Joint Strike Fighter.

Canceling AETP would leave the Air Force with only one advanced engine development program — the Next Generation Adaptive Propulsion effort that will eventually power the manned, sixth-generation fighter set to be a part of the service’s Next Generation Air Dominance family of systems. That effort is set to narrow down to a single vendor by the end of 2024, said John Sneden, director of the service’s propulsion directorate.



“If we end up with one vendor there, and we don’t move forward with AETP, that vendor could actually get us into a place where we have, essentially, a reduced advanced propulsion industrial base. So we are concerned about it,” he told reporters during the Air Force’s Life Cycle Industry Days conference.

“The perception I think that’s out there is that we’re maintaining, if not advancing, our military advantage in propulsion. And that’s always been because we’ve always had the world’s greatest advantage in propulsion,” he said. “But the reality is that our lead is starting to — we’re essentially stagnating, and we’re starting to lose.”

RELATED: F-35 engine rivals prepare for another clash

While Pratt & Whitney, General Electric and Rolls Royce dominate the propulsion market for military aviation, only Pratt & Whitney and GE are involved in AETP and NGAP.

https://breakingdefense.com/2022/08/adv ... -official/
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Unread post20 Aug 2022, 08:05

Corsair1963 wrote:Very confused.....If, the XA100/XA101 are maturing nicely and offering such good performance gains over the existing F119/F135. Why would the USAF start all over and design another engine? Plus, could such an engine even be ready in time for the NGAD???


Because AETP might have wrong size and it might be optimized for wrong thing for NGAD?

AETP will be sized quite equal to F135, in both physical size and inlet size.

But they probably do not want to make a plane that has twice the engine weight and twice the inlet drag of F-35?

They will probably want an engine that has about the size and air requirements of F119, so that it needs something like 20% less air than F135, to make a plane that is not much bigger than F-22. The engine core size might still be very close (or exactly the same) to the core size of AETP, so that bypass ratios in comparable modes are smaller in NGAP than AETP.

Also, with the name of "Next Generation Adaptive Propulsion Program". Then maybe its just a development of the XA100/XA101 Adaptive Cycle Engines of today?


Yes, something very close to AETP with reduced fan size, just like F135 is based on F119 but with enlarged fan. So development of AETP will also work towards development of this NGAP.

Or maybe the core is slightly smaller on NGAP but then it will be just very slightly downscaled.
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Unread post22 Aug 2022, 07:50

hkultala wrote:
Corsair1963 wrote:Very confused.....If, the XA100/XA101 are maturing nicely and offering such good performance gains over the existing F119/F135. Why would the USAF start all over and design another engine? Plus, could such an engine even be ready in time for the NGAD???


Because AETP might have wrong size and it might be optimized for wrong thing for NGAD?

AETP will be sized quite equal to F135, in both physical size and inlet size.

But they probably do not want to make a plane that has twice the engine weight and twice the inlet drag of F-35?

They will probably want an engine that has about the size and air requirements of F119, so that it needs something like 20% less air than F135, to make a plane that is not much bigger than F-22. The engine core size might still be very close (or exactly the same) to the core size of AETP, so that bypass ratios in comparable modes are smaller in NGAP than AETP.

Also, with the name of "Next Generation Adaptive Propulsion Program". Then maybe its just a development of the XA100/XA101 Adaptive Cycle Engines of today?


Yes, something very close to AETP with reduced fan size, just like F135 is based on F119 but with enlarged fan. So development of AETP will also work towards development of this NGAP.

Or maybe the core is slightly smaller on NGAP but then it will be just very slightly downscaled.



Sounds like you're wildly speculating to me... do you have anything to support those claims?
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Unread post22 Aug 2022, 10:09

Corsair1963 wrote:
hkultala wrote:
Corsair1963 wrote:Very confused.....If, the XA100/XA101 are maturing nicely and offering such good performance gains over the existing F119/F135. Why would the USAF start all over and design another engine? Plus, could such an engine even be ready in time for the NGAD???


Because AETP might have wrong size and it might be optimized for wrong thing for NGAD?

AETP will be sized quite equal to F135, in both physical size and inlet size.

But they probably do not want to make a plane that has twice the engine weight and twice the inlet drag of F-35?

They will probably want an engine that has about the size and air requirements of F119, so that it needs something like 20% less air than F135, to make a plane that is not much bigger than F-22. The engine core size might still be very close (or exactly the same) to the core size of AETP, so that bypass ratios in comparable modes are smaller in NGAP than AETP.

Also, with the name of "Next Generation Adaptive Propulsion Program". Then maybe its just a development of the XA100/XA101 Adaptive Cycle Engines of today?


Yes, something very close to AETP with reduced fan size, just like F135 is based on F119 but with enlarged fan. So development of AETP will also work towards development of this NGAP.

Or maybe the core is slightly smaller on NGAP but then it will be just very slightly downscaled.



Sounds like you're wildly speculating to me....do you have anything to support those claims???


Nothing hard, only speculation, that's why I used terms "might" and "maybe" and "probably"

But two AETP engines would mean that the plane would either be very big or would have insane T/W ratio.

NGAD/PCA is supposed to supercruise fast and far, not to have insane T/W ratio for insane acceleration and very high sustained turn rate for vietnam-style dogfights. On reasonable-sized (only slightly bigger than F-22) airframe, it does not need 43 tonnes of afterburning thrust, 35-40 tonnes is enough. It instead needs something like 26 tonnes of dry thrust (for that high speed supercruise), and it does not need AETP/F135-sized engine for that, F119-sized engine is enough for that.

And I don't see any need to go much bigger than F-22. When the engines have the same size and weight, on slightly bigger airframe they can already fit much more fuel than F-22 has. With both much more fuel, more economical engine, and slightly less drag (due to aerodynamics less optimized for maneuverability) they can then have much longer range.
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Unread post22 Aug 2022, 23:57

hkultala wrote:
Sounds like you're wildly speculating to me....do you have anything to support those claims???


Nothing hard, only speculation, that's why I used terms "might" and "maybe" and "probably"

But two AETP engines would mean that the plane would either be very big or would have insane T/W ratio.

NGAD/PCA is supposed to supercruise fast and far, not to have insane T/W ratio for insane acceleration and very high sustained turn rate for vietnam-style dogfights. On reasonable-sized (only slightly bigger than F-22) airframe, it does not need 43 tonnes of afterburning thrust, 35-40 tonnes is enough. It instead needs something like 26 tonnes of dry thrust (for that high speed supercruise), and it does not need AETP/F135-sized engine for that, F119-sized engine is enough for that.

And I don't see any need to go much bigger than F-22. When the engines have the same size and weight, on slightly bigger airframe they can already fit much more fuel than F-22 has. With both much more fuel, more economical engine, and slightly less drag (due to aerodynamics less optimized for maneuverability) they can then have much longer range.


Honestly, the plan to incorporate the AETP/ACE into the NGAD is nothing new and has been planned for many many years now. Clearly, they would have factored all of that into the new 6th Generation Fighter.

Again something is going on that we are likely not aware of...
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Unread post25 Aug 2022, 07:08

USAF Warns F-35 Reengine Decision Needed For Health Of Industrial Base
19 Aug 2022 Brian Everstine

"The U.S. Air Force is aggressively pushing for the reengining of its Lockheed Martin F-35 fleet while simultaneously proceeding with a highly classified approach to powering its next-generation fighter, arguing it is not just the aircraft that needs approval for the new powerplants—it’s about the health of the industrial base as well.

The service’s Adaptive Engine Transition Program (AETP) is reaching its final stages, with GE Aviation and Pratt & Whitney’s three-stream propulsion systems undergoing evaluations ahead of an expected decision next year. The Air Force’s F-35A variant currently lacks power and sufficient thermal management capacity for upcoming technological upgrades, and Air Force Secretary Frank Kendall said he supports an adaptive engine to provide the thrust and range he wants....

...F-35 Decision Coming Soon...
...This decision will come in the Air Force’s fiscal 2024 budget request to be released next year, potentially kicking off another five-year program to move through the engineering and manufacturing development (EMD) phase. This will include flight testing and integration, with production at the end of the decade, Sneden said. There are no plans yet for a flight demonstration, but the program is ready to move to EMD and ensure it is “tested and validated in every possible way,” he added.

While Congress has been pushing the Air Force to move ahead with AETP for the F-35, calling for a plan for installation by 2028, other lawmakers have recently raised concerns about the cost. This will be several billion dollars, Kendall said, in addition to the ongoing research and development funding.

“I don’t want to limp along, spending R&D money on a program that either we can’t afford or that we’re just not going to get agreement on among the different services,” Kendall said. “So we have got to get to a decision on it.”

The Air Force has hoped the Navy would express interest—with the AETP offerings able to fit in the F-35C, though not currently in the Marine Corps’ F-35B. However, the Navy has not publicly expressed interest in the engines. GE, for example, says it has designed its XA100 from the beginning to fit in the F-35C and has had ongoing discussions with the Navy, says David Tweedie, vice president and general manager of GE’s Edison Works Advanced Products unit. Fitting the engine offering to the distinct F-35 variants was an additional challenge because of different characteristics of the C model—it is bigger, has more tightly packaged requirements in the engine bay and has a larger tail hook. However, GE’s engine offering has a 100% part-number commonality for the A and C models, Tweedie says, and the company is starting to research adapting it for the B model.

“We’re doing our best to make sure that we have a compelling offering for the Navy,” Tweedie says.

Spreading out the cost will help, with the bill expected to reach up to $6 billion to bring on the new engine for the F-35A by 2030. Despite the price tag, however, Sneden argues the spending will be needed. If an AETP engine is not picked, the service could go with an upgrade to the current F135, like Pratt’s F135 Enhanced Engine Package, or other modifications that would still need to be bought.

“Regardless of the path that we choose for the F-35, we’re going to spend a lot of money to get to where we need to be, whether it’s an upgrade to the current F135, the engine enhancement program, or if it’s an AETP engine,” Sneden said. “Our perspective is: ‘You can optimize for performance or you can optimize for trivariant commonality.’ We think the warfighter deserves the performance attributes that AETP can deliver. And frankly, what I’ll offer to you is that winning is expensive, and we can’t afford to lose.”..." [THEN NGAD]

Source: https://aviationweek.com/defense-space/ ... trial-base
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Unread post26 Aug 2022, 18:26

I did not see any true cutaway about the GE XA100 engine, except the fancy infographics, but there the shafts are rotating with the same direction. The P&W F135 family (like the F119) has a counter-rotating shafts, where the most important benefit is not just the lack of one stator between the last and first stages of the two spools, but the almost elliminated precession. Without the preciession, the airplane has a better high AoA maneuvering capability, because the control surfaces have less required work to compensate the high AoA departure.
The shafts precession is a valid issue - like the propeller driven airplanes have it at take off, high RPM differnece or high AoA situation - so a counter rotating shaft design could be helpful.
If the XA100 has a similar rotation shaft design, the FbW has more workload to keep the same high AoA controllability and handling characteristics.
From this standpoint the XA100 integration would not be a simple "plug and play" thing. At high AoA the whole attitude is goind to be different.
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Unread post26 Aug 2022, 20:47

allesmorobranna wrote:I did not see any true cutaway about the GE XA100 engine, except the fancy infographics, but there the shafts are rotating with the same direction. The P&W F135 family (like the F119) has a counter-rotating shafts, where the most important benefit is not just the lack of one stator between the last and first stages of the two spools, but the almost elliminated precession. Without the preciession, the airplane has a better high AoA maneuvering capability, because the control surfaces have less required work to compensate the high AoA departure.
The shafts precession is a valid issue - like the propeller driven airplanes have it at take off, high RPM differnece or high AoA situation - so a counter rotating shaft design could be helpful.
If the XA100 has a similar rotation shaft design, the FbW has more workload to keep the same high AoA controllability and handling characteristics.
From this standpoint the XA100 integration would not be a simple "plug and play" thing. At high AoA the whole attitude is goind to be different.


While it is true that both the F119 and F135 engines have counterrotating high and low spools, P&W was unable to eliminate the stator vanes between the high and low turbine rotors, although this was the original design concept. They found that with the high levels of expansion in these high work single stage turbines, the hot gas flow exiting the high turbine tended to streamline straight into the middle of the low turbine blades. The added low turbine vanes have very little flow turning camber, but are 3D shaped to spread the flow evenly across the LPT blades from root to tip. The F135, in addition to this low turbine inlet vane, has a more conventional turning vane between the blade stages to split the work between the two rows of LPT blades.

FYI - the Harrier engine also had counterrotating high and low rotors for low speed and VTOL handling. In addition to the gyroscopic precession concern that occur with pitch and yaw rates, the counterrotating rotors offset any torque reaction of the engine. While jet engines have no external torque at steady state conditions, they have a very large torque opposite the direction of rotation during fast throttle movement rotor acceleration. Under low airspeed / hover conditions this accel torque could easily overpower the available control authority and roll the aircraft into an uncontrollable position. Each spool of a counterrotating dual spool engine applies this accel torque in opposite directions, cancelling much of it out.
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Unread post27 Aug 2022, 15:59

f119doctor wrote:
allesmorobranna wrote:I did not see any true cutaway about the GE XA100 engine, except the fancy infographics, but there the shafts are rotating with the same direction. The P&W F135 family (like the F119) has a counter-rotating shafts, where the most important benefit is not just the lack of one stator between the last and first stages of the two spools, but the almost elliminated precession. Without the preciession, the airplane has a better high AoA maneuvering capability, because the control surfaces have less required work to compensate the high AoA departure.
The shafts precession is a valid issue - like the propeller driven airplanes have it at take off, high RPM differnece or high AoA situation - so a counter rotating shaft design could be helpful.
If the XA100 has a similar rotation shaft design, the FbW has more workload to keep the same high AoA controllability and handling characteristics.
From this standpoint the XA100 integration would not be a simple "plug and play" thing. At high AoA the whole attitude is goind to be different.


While it is true that both the F119 and F135 engines have counterrotating high and low spools, P&W was unable to eliminate the stator vanes between the high and low turbine rotors, although this was the original design concept. They found that with the high levels of expansion in these high work single stage turbines, the hot gas flow exiting the high turbine tended to streamline straight into the middle of the low turbine blades. The added low turbine vanes have very little flow turning camber, but are 3D shaped to spread the flow evenly across the LPT blades from root to tip. The F135, in addition to this low turbine inlet vane, has a more conventional turning vane between the blade stages to split the work between the two rows of LPT blades.

FYI - the Harrier engine also had counterrotating high and low rotors for low speed and VTOL handling. In addition to the gyroscopic precession concern that occur with pitch and yaw rates, the counterrotating rotors offset any torque reaction of the engine. While jet engines have no external torque at steady state conditions, they have a very large torque opposite the direction of rotation during fast throttle movement rotor acceleration. Under low airspeed / hover conditions this accel torque could easily overpower the available control authority and roll the aircraft into an uncontrollable position. Each spool of a counterrotating dual spool engine applies this accel torque in opposite directions, cancelling much of it out.

Someone should take a page with piston engine designs and give ICE motors counter-rotating shafts connected with gears or something. Nothing worse than taking off from a complete stop and having that torque slip you sideways. Well, maybe not. :)
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Unread post28 Aug 2022, 00:03

For propeller aircraft, you need counter rotating props to offset torque, P-factor, and spiraling prop wash hitting the rudder, all trying to roll and side slip on the aircraft at low air speeds. Many of the WW2 fighters required a slow throttle advance during go-arounds to keep from rolling and crashing inverted. Lots of attempts at coaxial counter rotating props thru the war, but most were abandoned with the advent of the jet age.
P&W FSR (retired) - TF30 / F100 /F119 /F135
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