Engine upgrades

Unread postPosted: 25 Mar 2019, 22:23
by edpop
The US Navy awarded United Technologies subsidiary Pratt & Whitney an $18.4 million contract modification for additional funding of the F-135. The F-135 is a mixed-flow afterburning turbofan developed specifically for the F-35 Lightning II. The engine’s propulsion system powers all three variants of the fighter aircraft. According to Pratt & Whitney it delivers more than 40.000 Ibs. of thrust. There are three F135 variants: the -100 engine, -400 engine, and the -600 engine. The -400 is similar to the -100, the most important difference being the use of salt-corrosion resistant materials. The initial F-35s went into production with the F135 engines. However, Pratt and Whitney is cooperating with the US Navy on a two-block improvement plan for the F135 engine. The goals of Block 1 are a 10 percent increase in thrust and a 5 percent lower fuel burn. The plans also include better cooling technology for turbine blades. This would increase the longevity of the engine as well as reduce maintenance costs. The goal of Block 2 is to work with the US Air Force's Adaptive Engine Transition Program, intending to introduce technology for an engine rated at 45,000 lb of thrust, to be used in a sixth-generation fighter. Work under the current deal will take place within the US as well as the UK and is scheduled to be finished in March 2022.

Re: Engine upgrades

Unread postPosted: 25 Mar 2019, 23:05
by fbw
Edpop- where is this news article from? Last year they split the AETP, a 45,000lb thrust class engine for possible F-35 propulsion upgrades and a separate engine for whatever platform(s) come out of PCA.

While neither here nor there, Personally I think P&W is pushing growth options 1&2 to avoid possibility of losing a re-engining effort in the 2020’s to GE.

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

Re: Engine upgrades

Unread postPosted: 26 Mar 2019, 01:43
by wrightwing
Those are understated numbers, anyhow. A 10% increase over 43k, is over 47K. The AETP motor is supposed to provide 20 to 25% more thrust (or 51.6K to 53.75K.) They've already run the standard motors to 51K, so those are well within the realm of probability.

Re: Engine upgrades

Unread postPosted: 26 Mar 2019, 02:35
by edpop
fbw wrote:Edpop- where is this news article from? Last year they split the AETP, a 45,000lb thrust class engine for possible F-35 propulsion upgrades and a separate engine for whatever platform(s) come out of PCA.

While neither here nor there, Personally I think P&W is pushing growth options 1&2 to avoid possibility of losing a re-engining effort in the 2020’s to GE.

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

From Defense Industry Daily...........

Re: Engine upgrades

Unread postPosted: 26 Mar 2019, 05:11
by madrat
I'd like to see B-1B get these new engines on a service life extension program. Instead of retiring B-1B turn it into a rapid forward deployment tanker with a swap-able kit. They need to retain the ability to be maintained as a venue to drop smart ordnance like they've been utilized in Afghanistan.

Re: Engine upgrades

Unread postPosted: 06 Aug 2019, 17:33
by spazsinbad
Lots of engine upgrades thread posts so I'll plonk this here. Why is the F-35 under ranged? Just baffling - because it ain't.
ANALYSIS: F-35's next engine to reach for more range
06 Aug 2019 Garrett Reim

"One criticism – among many – of the Lockheed Martin F-35 Lightning II is that the fighter lacks the range needed to conduct long-range stealth strike missions. While Lockheed Martin has studied adding external fuel tanks to extend the aircraft's range, slinging the bulky hardware under the F-35 would ruin its minimal radar cross section, giving away the stealth fighter's chief advantage.

In place of extra onboard fuel, the US Navy (USN) has boosted the flight endurance of its F-35C variant by using its Boeing F/A-18E/F Super Hornet as a substitute in-flight refuelling tanker. The service is also funding the development of four Boeing MQ-25A Stingray unmanned in-flight refuelling tankers for $805 million....

...The USAF is looking at how the F-35 can do more with its fuel capacity. One important effort is the service's Adaptive Engine Transition Program, which aims to create a novel engine that has not only more power, but also more fuel economy.

Adaptive engines work by varying the volume of air flow that bypasses the turbine core by opening a third stream when flying in cruise mode. This third flow – in addition to core flow and bypass flow – increases the engine's efficiency in producing thrust and also creates a new heat sink within the engine, allowing for further fuel efficiency gains from increased core temperature. The result is an engine that can play the turbofan's efficiency trick of running a large bypass ratio when cruising – while retaining the raw power of a turbojet in other situations....

...For its part, GE Aviation announced the successful completion of the XA100 detailed design process in February 2019. The company believes the engine could result in a 35% increase in range and a 50% improvement in loiter time. That range improvement applied to the F-35C would add 420nm – taking range for the USN's variant to 1,620nm.

"In the Pacific theatre of operations this is significant, allowing either operations from greater distances or more time to operate at the combat edge," says USAF Major General Larry Stutzriem (retired), now director of research with the Mitchell Institute for Aerospace Studies. "This improvement could also allow F-35s to drop from their tanker support earlier, keeping those extremely vulnerable aircraft further away from adversary defences."..."

Source: https://www.flightglobal.com/news/artic ... ge-459856/

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 03:08
by weasel1962
The engines of innovation thread did cover the AETP upgrades.

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 03:12
by eloise
1620 nm combat radius is insane, holy sh...t :o

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 03:41
by quicksilver
eloise wrote:1620 nm combat radius is insane, holy sh...t :o


Range...not radius, to wit — “That range improvement applied to the F-35C would add 420nm – taking range for the USN's variant to 1,620nm.”

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 04:36
by Corsair1963
wrightwing wrote:Those are understated numbers, anyhow. A 10% increase over 43k, is over 47K. The AETP motor is supposed to provide 20 to 25% more thrust (or 51.6K to 53.75K.) They've already run the standard motors to 51K, so those are well within the realm of probability.



Yes and many sources give the range of the F-35A/C at ~ 1,200 miles. When in fact we know it to be more in the real world....


So, in all honesty an F-35 equipped with an ACE Engine (XA-100 or XA-101) may actually have a range in the 1,800 -1,900 miles! (i.e. internal fuel only)

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 04:45
by element1loop
quicksilver wrote:
eloise wrote:1620 nm combat radius is insane, holy sh...t :o


Range...not radius, to wit — “That range improvement applied to the F-35C would add 420nm – taking range for the USN's variant to 1,620nm.”


Now that's an "Air-Dominance" fighter!

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 05:20
by quicksilver
wrightwing wrote:Those are understated numbers, anyhow. A 10% increase over 43k, is over 47K. The AETP motor is supposed to provide 20 to 25% more thrust (or 51.6K to 53.75K.) They've already run the standard motors to 51K, so those are well within the realm of probability.


The question of the day is, ‘how much more thrust can be produced without changing the inlet geometry?’

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 05:44
by element1loop
Say you ''loiter' it out at 438KTAS = M0.75 @ FL320 to a tanker, maximize range extension from there, release weapon, fly back to a tanker then RTB. That's so much range you'd start to encounter pilot fatigue, 'solved' via super-cruising with a higher thrust allowance (and at higher altitude for less drag).

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 06:27
by quicksilver
element1loop wrote:Say you ''loiter' it out at 438KTAS = M0.75 @ FL320 to a tanker, maximize range extension from there, release weapon, fly back to a tanker then RTB. That's so much range you'd start to encounter pilot fatigue, 'solved' via super-cruising with a higher thrust allowance (and at higher altitude for less drag).


Pilots flying in the ME for the last 17+ years have been routinely flying very, very long sorties. Would fatigue be a factor? Yes, but not sure how much different it would be from what they’ve done for a very long time already. My sense is that sortie duration would remain similar but it would cut down (not eliminate) on tanker demands.

I would also offer that loiter speeds (max endurance) are used when you have arrived where you wanna be; max range (which would be somewhat faster and at somewhat higher fuel flow) gets one the most distance for the least amount of fuel. What we don’t know is where in the performance envelope (speed/fuel flow) those quoted improvements reside.

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 07:47
by element1loop
quicksilver wrote:
element1loop wrote:Say you ''loiter' it out at 438KTAS = M0.75 @ FL320 to a tanker,


... I would also offer that loiter speeds (max endurance) are used when you have arrived where you wanna be; max range (which would be somewhat faster and at somewhat higher fuel flow) gets one the most distance for the least amount of fuel. What we don’t know is where in the performance envelope (speed/fuel flow) those quoted improvements reside.


Sure, just using that speed as a lower threshold to get some feel for endurance time, speed and range before it's throttled-up. I suspect loiter, max-endurance (not necessarily the same V) and max-range cruise speed are all going to be quite close to each other at mid to upper jetstream altitude range.

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 11:05
by quicksilver
“Sure, just using that speed as a lower threshold to get some feel for endurance time, speed and range before it's throttled-up. I suspect loiter, max-endurance (not necessarily the same V) and max-range cruise speed are all going to be quite close to each other at mid to upper jetstream altitude range.”

How do you define loiter? What is it’s purpose? In other words, if I looked ‘loiter’ up in your flight manual, how would it be different from max endurance?

http://www.eaa1000.av.org/technicl/perf ... tm#Figure_

We’ve talked about this before, but apart from max end and max range everything else is circumstantial. For example, if I was IMC with a wingman (necessarily in parade formation), max end or max range would make formation keeping difficult for that wingy because the jet is so far back on the power that its response to throttle movements lags; not good. So, you’d pick something a little faster that met mission requirements (make your land time...not run out of gas...give yourself some reserves, etc) and put the jet in an rpm range that provided better throttle response.

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 14:45
by element1loop
quicksilver wrote:How do you define loiter? What is it’s purpose? In other words, if I looked ‘loiter’ up in your flight manual, how would it be different from max endurance?


Best-endurance speed is usually a bit slower than a specified loiter speed, I've always seen that as a result of loiter involving banking in orbits so having more speed margin and performed for a shorter period so a slightly higher flow doesn't matter, it's temporary. While best-endurance is sustained in a straight line so a stability margin is not needed thus lower flow rate and slightly more time up your sleeve.

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 23:31
by weasel1962
quicksilver wrote:
eloise wrote:1620 nm combat radius is insane, holy sh...t :o


Range...not radius, to wit — “That range improvement applied to the F-35C would add 420nm – taking range for the USN's variant to 1,620nm.”


+1

Re: Engine upgrades

Unread postPosted: 07 Aug 2019, 23:47
by sprstdlyscottsmn
the 600nm radius was also with sub-optimal cruise.

Re: Engine upgrades

Unread postPosted: 08 Aug 2019, 21:07
by marauder2048
quicksilver wrote:How do you define loiter? What is it’s purpose? In other words, if I looked ‘loiter’ up in your flight manual, how would it be different from max endurance?



I've only ever seen it defined as the portion of on-station time flown at the max-endurance fuel flow rate.

And since the on-station average fuel consumption is going to be distorted upwards by the
attack fuel flow requirements, the interplay between those those two fuel flow rates is what typically
guides planners.

Re: Engine upgrades

Unread postPosted: 09 Aug 2019, 19:22
by playloud
quicksilver wrote:
eloise wrote:1620 nm combat radius is insane, holy sh...t :o


Range...not radius, to wit — “That range improvement applied to the F-35C would add 420nm – taking range for the USN's variant to 1,620nm.”

And we know the 1,200 nmi number is already below the spec. It demonstrated a 670 nmi combat radius (A2G), per the SAR. That would make its range at least 1,340 nmi before the upgrade. Internal A2A would be even higher. F-35A is listed at 760 nmi for A2A, giving it a range of 1,520 nmi (before upgrade). The C model should give similar numbers.

Re: Engine upgrades

Unread postPosted: 18 Sep 2019, 15:03
by taog
Pratt Defining Engine Upgrade Package For Block 5 F-35

"...The intent is to deliver options for improving thrust by more than 10-12%, reducing fuel consumption by more than 5-6%, increasing vertical lift by about 2% and increasing overall power and thermal management capacity, Bromberg says. ..."

https://aviationweek.com/defense/pratt- ... ock-5-f-35

Re: Engine upgrades

Unread postPosted: 19 Sep 2019, 13:03
by mixelflick
More thrust for.... expanded super-cruise? Or just more "umph" to accelerate/maneuver. I get the greater range requirement, just wondering what extra thrust will allow it to do vs. what's currently possible?

Requirements were to have F-16 like speed/acceleration and F-18 like nose pointing authority. By all accounts, they've succeeded. But I'd love for it to exceed those F-16/18 specs considerably, and these new engines will hopefully get it there.

Re: Engine upgrades

Unread postPosted: 19 Sep 2019, 22:32
by wrightwing
I think that acceleration, climb rates, take off/bring back weights, range, and loiter, were probably higher priorities, but I'm sure it doesn't hurt the cruise speed in dry thrust (and that's with the conservative 10-12% improvement. There are other claims in the 20+% range, as well.)

Re: Engine upgrades

Unread postPosted: 19 Sep 2019, 23:20
by falcon.16
taog wrote:Pratt Defining Engine Upgrade Package For Block 5 F-35

"...The intent is to deliver options for improving thrust by more than 10-12%, reducing fuel consumption by more than 5-6%, increasing vertical lift by about 2% and increasing overall power and thermal management capacity, Bromberg says. ..."

https://aviationweek.com/defense/pratt- ... ock-5-f-35


Is this option Grown 1.0?

Re: Engine upgrades

Unread postPosted: 19 Sep 2019, 23:41
by f119doctor
Per the AvWeek article, it is Growth option 2, or a variant of it.

Re: Engine upgrades

Unread postPosted: 20 Sep 2019, 00:42
by jetblast16
'There are other claims in the 20+% range, as well'

I'm not doubting you but do you have any links? I saw similar claims about potential engines for the now "Century Series"-styled NGAD, gonad, or whatever the heck they call it these days, in the 50k - 60k thrust class range.

Re: Engine upgrades

Unread postPosted: 20 Sep 2019, 01:22
by falcon.16
f119doctor wrote:Per the AvWeek article, it is Growth option 2, or a variant of it.


Thanks.

I can not read the article, is blocked only for subscribers.

Re: Engine upgrades

Unread postPosted: 20 Sep 2019, 01:40
by spazsinbad
falcon.16 wrote:
f119doctor wrote:Per the AvWeek article, it is Growth option 2, or a variant of it.

Thanks. I can not read the article, is blocked only for subscribers.

The Aviation WEAK article can be viewed by NON-Subscribers who register (such as MOI) - just register for FREE but you will still be a NONsubscriber.
Pratt & Whitney Defining F-35 Engine Upgrade Package
18 Sep 2019 Steve Trimble

"Pratt & Whitney is defining a new engine upgrade option for F-35s delivered starting after 2026, says Matthew Bromberg, president of Military Engines.

The upgrades, the details of which will be defined in about six months, are focused on improvements to the fan and the engine accessories, Bromberg told Aerospace DAILY during a Sept. 17 interview on the sidelines of the Air Force Association’s Air, Space and Cyber Conference.

The intent is to deliver options for improving thrust by more than 10-12%, reducing fuel consumption by more than 5-6%, increasing vertical lift by about 2% and increasing overall power and thermal management capacity, Bromberg says.

Those targets are the proposed baseline improvements advertised for the Growth Option 2.0 upgrade, which remains in discussions for insertion beyond Block 4.2 aircraft delivered starting in 2026, he says.

P&W originally proposed a Growth Option 1.0 upgrade package that offered only thrust and fuel improvements, but no extra capacity for power generation and cooling.

“We found it didn’t resonate because it didn’t have power and thermal management,” Bromberg says.

The Growth Option (GO) and Engine Enhancement Package (EEP) upgrades all stem from technologies developed under the Adaptive Engine Technology Program, which is funded by the Air Force Research Laboratory to design a new engine core.

Pratt & Whitney completed the detailed design review of the XA101 demonstrator engine recently, Bromberg says.

Editor’s Note: The article was corrected to update the timing for EEP and GO 2.0 availability.

Source: https://aviationweek.com/defense/pratt- ... de-package

Re: Engine upgrades

Unread postPosted: 20 Sep 2019, 01:42
by wrightwing
jetblast16 wrote:'There are other claims in the 20+% range, as well'

I'm not doubting you but do you have any links? I saw similar claims about potential engines for the now "Century Series"-styled NGAD, gonad, or whatever the heck they call it these days, in the 50k - 60k thrust class range.

The ACE/AETP motors were supposed to have a ~20% thrust increase, ~50% improved loiter, and ~30 to 35% range increase.

Re: Engine upgrades

Unread postPosted: 20 Sep 2019, 01:44
by taog
falcon.16 wrote:
taog wrote:Pratt Defining Engine Upgrade Package For Block 5 F-35

"...The intent is to deliver options for improving thrust by more than 10-12%, reducing fuel consumption by more than 5-6%, increasing vertical lift by about 2% and increasing overall power and thermal management capacity, Bromberg says. ..."

https://aviationweek.com/defense/pratt- ... ock-5-f-35


Is this option Grown 1.0?


Not op1 but op2.

"... Those targets are the proposed baseline improvements advertised for the Growth Option 2.0 upgrade, which remains in discussions for insertion beyond Block 4.2 aircraft delivered starting in 2026, he says. ..."