Lockheed to Offer new Fighter to Japan Using Hybrid of F-22 & F-35 Tech

originally posted by: nwtrucker

originally posted by: RadioRobert
You'd go with the F119, I'm sure. The F135 is a derivative of the F119 already, but the F135 is longer, and you'd have to figure out if the nozzle could take the heat, how much strength/weight you need to add structurally.
I imagine it'd be tempting to try to shoehorn in the extra thrust and take advantage of the existing supply line(s) for the F135, but I don't know that you could do it without a major redesign aft. Seems cheaper/faster, etc to minimize planform, structural, aero changes.

Correct me if I'm wrong, but my understanding is the F-119 is a very low by-pass engine. It's designed for the high speed, air superiority role. The F-135 is about 20% bigger in diameter and a high by-pass, turbo fan styled engine who's performance stands out in the sub-sonic role.

Mix the two concepts and you'd end up with something not as good as either.

A 20% increase in fan diameter would be a huge increase in bpr and steal more power from the core.
I seem to remember some discussion at the time of development that the diameter had not changed much, the core stayed essentially the same, and they added a stage to the LP turbine (hence the length increase).
Expanding the fan 20% and adding a stage would presumably increase thrust quite a bit more than the reported 14%, would it not? Without expanding the diameter, and using the same core, the bpr isn't going to change. Really the big change with bpr for the same thrust level is exhaust velocity, which relates to efficiency at different speeds. Performance is otherwise simple thrust-weight dynamics. Happy to be shown actual specifics to inform my opinion.

I think F119 production has been shut down around 2013. So it would have to be restarted too.

This is a wrinkle I didn't give any thought to in my late night/early morning rambling...

a reply to: nwtrucker

Both engines are 46 inches in diameter. The F135 has a 43 inch inlet, and maximum diameter of 46 inches. The length is slightly longer at just over 18 feet, compared to just under 17 feet for the F119.

originally posted by: Zaphod58
a reply to: nwtrucker

Both engines are 46 inches in diameter. The F135 has a 43 inch inlet, and maximum diameter of 46 inches. The length is slightly longer at just over 18 feet, compared to just under 17 feet for the F119.

Hmmm, weird. Maybe it was a misprint. I remember that comment, but it goes well back in time. I stand corrected. thanks.

What about the BPR? I held the belief the low by-pass of the F-119 might be part of the slow energy recovery the Raptor is subject to. Assuming the real reason is the Raptor can get a lot slower than those German EFs realized.

a reply to: RadioRobert


OK. Seems I bought into some BS from the day. BPR is close if Wiki is to be believed and we know some of those specs are outright Bull. Can't see bull on size specs, though. 30-1 vs 28-1 for the 135.

Yet the opinions I've seen is the F-35 is a beast in the sub-sonic range where as the Raptor gets nastier the faster she goes.

In any event, thanks.

a reply to: nwtrucker

The 20% increase was when they were originally developing the F119. The power requirements were increased, so they increased the fan size of the prototype engine.

The F119 has a 0.30-0.45:1 bypass ratio. The F135 has a 0.57:1 bypass ratio, and a 0.51:1 hover ratio. The conventional pressure ratio is 28:1/29:1 on the F135, and the F119 is estimated at 35:1.

originally posted by: Zaphod58
a reply to: nwtrucker

The 20% increase was when they were originally developing the F119. The power requirements were increased, so they increased the fan size of the prototype engine.

The F119 has a 0.30-0.45:1 bypass ratio. The F135 has a 0.57:1 bypass ratio, and a 0.51:1 hover ratio. The conventional pressure ratio is 28:1/29:1 on the F135, and the F119 is estimated at 35:1.

Ahh, that clears it up! Wiki's BPRs are a bit different.

originally posted by: nwtrucker
a reply to: RadioRobert


OK. Seems I bought into some BS from the day. BPR is close if Wiki is to be believed and we know some of those specs are outright Bull. Can't see bull on size specs, though. 30-1 vs 28-1 for the 135.

Yet the opinions I've seen is the F-35 is a beast in the sub-sonic range where as the Raptor gets nastier the faster she goes.

In any event, thanks.

Thrust is pretty much thrust. Assuming some increase in bpr, the efficiency would be higher in the F135 at lower speeds. And the F119 would have higher efficiency at higher speed. But efficiency or no, 43,000lbs of thrust is still more beastly than 37,500lbs.
I'm not really sure there's such an increase in bpr, however, since the diameter and core stayed essentially the same. Not sure I'd read much into the press clippings without some sort of actual data to look at. Lots of anaysis with lots of estimates for both engines.

Its an interesting premise. If Japan is indeed willing to foot the bill for the startup costs an notional F-22B would be a nice way to bolster the existing force and add a upgraded capacity to the USAF but........

1) The F-35 crowd will not want its funding jeopardized nor would it want to cannibalize orders
2) While derived from the F-119, the F-135 may not be as easy of a fit. The inlet geometry may require changes which could effect the RCS. Also my understanding is that many of these designs are pushing the thermal envelope and can the structure handle the additional thermal requirements?
3) The F-135 weights more as well so it may be easier to simply keep an upgraded version of the f119 and simply update the electronics/avionics which are decades old.
4) it was a dumb choice by the Bush and Obama administration to terminate production and stupider yet to deny export to Japan, Australia, Israel, and the UK

The reality is this seems more wishful thinking than anything else.

a reply to: FredT

I think it's got a pretty good shot at going somewhere. I don't think it's going to be an actual F-22/F-35 hybrid, but more something that can do both missions, and has near F-35 sensor fusion. They're looking for something bigger, that has longer range and endurance, and can do air dominance, as well as antishipping and strike missions.

This is a pipedream IMO. Japan wont invest multiple billion US-$ (10+ billion, lets be honest) in development upfront for little to no capability gain. The F-35 is not a perfect fit, but it will get the job for a fraction of the total cost of a new fighter development.
F-35Js and participation in a US 6th Gen Project later down the road is the way to go.

www.flightglobal.com...

A bit more info, but not much...with one juicy tidbit:

“We’ve finished the testing that we planned,” he says. “Nothing is determined about the X-2’s future. We may do more testing.”

I hope they do. It's a beaut and would be a pity if it was consigned to an early grave after a short life.

More info here, too:

theaviationist.com...

originally posted by: Zaphod58
a reply to: FredT

I think it's got a pretty good shot at going somewhere. I don't think it's going to be an actual F-22/F-35 hybrid, but more something that can do both missions, and has near F-35 sensor fusion. They're looking for something bigger, that has longer range and endurance, and can do air dominance, as well as antishipping and strike missions.

Bigger than an F-22? Thats a big aircraft compared to a F-35 isnt it? Its in the YF-23 and T-50 territory.

I wonder if the YF-23 still has any design merits in 2018 or if modern design has surpassed that style?

However, being as though its near peer competition is the T-50 and J-20 which to me seem only slightly low observable from the front, perhaps Japan dont need 2018 bleeding edge stealth?

What keeps me wondering is the F-22 is now 20+ year old core technology...and it's STILL banned from export?

a reply to: Borys
It is not 'banned' and never was. Congress just prohibited funding through procurment funds.

www.congress.gov...

A foreign buyer could pick up the tap if they wanted to.

It wasn't overturned later to protect F-35 sales and because the Obama admin wanting to kill the program anyway.

a reply to: mightmight
Congratulations and thank you, thank you, thank you, for being one of the only people on this forum, or any other to correctly pick up on the fact that the F-22 was not "banned" from export but rather Congress banned funding in order to promote the F-22. The LOXCOM committee actually cleared export of the F-22 during the later Clinton administration for potential export to Australia, Britain, Canada and Japan. And yes, they didn't bother overturning it later because they really wanted to protect the F-35 in its infancy and because LM said "screw it, we can either sell a couple of hundred extra Raptors max, or we can sell double or more than that of F-35's". It didn't take a genius to work out which argument would win.

Now as for this proposal I actually agree with Zaphod that this proposal has a real half chance of getting some legs, and ironically for the very reason we agree on. The whole issue of "no export F-22 for you!" was never really solved, certainly not by the F-35 and frankly I wager that the 6th Gen is either as it is both probably realistically too far out and I'm not entirely sure the US Govt will allow any real export anyway if it is trying to protect an eroded technological lead. However an F-28.5(well it IS half way between the Raptor and Lightening) would serve both close export clients and offer a probably politically correct bridge between the F-22 and the 6th Gen. This is particularly relevant if the US wants to both update its air defence in light of growing threats and block obsolescence, maintain its industrial technical base and leverage off the existing F-35 effort to effectively use the same avionics but increase numbers of systems built. In fact I would wager that if done right we could see orders of a notional hybrid somewhere between 500 to 750 built, possibly higher if the international situation deteriorates. The UK alone could probably justify between 75-100 without trouble, Japan at least that many and Australia 50-75. Canada is an unknown quantity at this time but 50 is a reasonable bet if they pull their head out of their a*s and get real about continental defence. The US. can easily make up another 250 so that's 500 plus without stretching the imagination too far.

As for engines, who said it had to be an F-119 or F-135? All this debate about engine bypass ratios and TWR is misleading. Nobody said that it WOULD be an F-22 airframe, just that it would be a hybrid, the F-135 is less than 18" longer than the 119 anyway. Has anybody here considered a 3 stream powerplant may be the likely option, and that it would offer the ability to provide real world performance as both a Raptor like interceptor with high altitude, high speed, low bypass as well as low speed, high bypass performance a la the F-35?

As for costing , and risks, I'm betting this would be a tightly run program as the days of screwing around the US taxpayer as well as generally f**king up programs is over, and LM above all else knows it. I would bet that this would be a rapid type of program with very few risks taken and a tight development schedule, I would say most of it done inside of 7 years with real gains or its toast. I also expect that Japan will only pick up probably half of the development cost at best as the USAF will undoubtedly show interest.

Watch this space.

There is certainly an argument for an F-22/F-35 hybrid from a military perspective. The need is there (well, kinda) but the money isn’t. Neither is political will.

The UK MoD can barely afford the introduction of the F-35, replacing the Eurofighter (?) with a F-35/F-22 or growing the RAF by adding some 5 combat squadrons is not feasible. They are already struggling make ends meet and it wont get any better with Brexit and all.
Australia has similar issues, the F-35 purchase is stretched out over many years, there are a dozen important procurement projects in the pipeline and any fighter purchase is crazy politicized. The last thing they need is yet another debate on the lines of F-111 vs F-35.
Canada just pulled out of the F-35 program due to rising cost and some other stupid reasons. They are currently buying used Australian Super Hornets as an replacement. I don’t think they would be inclined to back this effort.

And as for the US – funding is limited there too. Future defense spending will very likely not increase (may very well even decrease) and is already insufficient to cover everything. Backing this effort means something else has to give. B-21, PCA, F-35 – take your pick. Most likely they would cut F-35 procurement which would increase units cost considerably, which would hurt exports, which would make the plane even more expensive etc… The F-35 procurement is built entirely on Lockheed producing them en masse. Cut back on procurement and continue to delay full scale production and it will turn ugly very quickly.
Like it or not, the western powers are locked in as far as the F-35 goes.

- For the UK, any potential adversary will at most have a limited number of 5th generation fighters, mostly 4th generation fighters, and an advanced IADS. I don't see a clear reason why an F-28.5 hybrid is going to be massively better than an F-35 at SEAD/DEAD and the Typhoon/F-35 combo will hold its own against 4th generation fighters. The UK is buying the F-35B for their carriers, so the F-35B is a given. The Typhoons are still new and could receive a mid-life-upgrade. Plus, the UK can barely afford its currently planned armed forces, and furthermore receives industrial offsets for being part of the F-35 program. I think the F-28.5 can only fit in if the international situation deteriorates significantly, defense spending increases significantly, or when the Typhoon starts getting old (2030-2040).

- In Australia the F-35 has huge momentum. 5 F-35's have been delivered and around 5 more are currently in production. The transition to the F-35 will be very rapid with one squadron per year transitioning - all the infrastructure to do this is being built at the moment. Industry receives work share and the Classic Hornet is rapidly becoming irrelevant and needs a replacement quickly. I think there is an opportunity to buy into the F-28.5 once 72 F-35's have been delivered and Australia could decide on transitioning the Super Hornet to the notional F-28.5, other aircraft, or notional Block 5+ F-35, we could also join the industrial team in their efforts. But again, we have to wait until RAAF F-35 FOC (2023) before we even hear a whisper of that, otherwise it would be political suicide and second guessing ourselves for no good reason.

- Canada:

Canada just pulled out of the F-35 program due to rising cost and some other stupid reasons. They are currently buying used Australian Super Hornets as an replacement. I don’t think they would be inclined to back this effort.

Technically Canada didn't pull out of the F-35 program, they remain a partner (unless this changed very recently). More like they paused their planned buy whilst they analyse options. Also they are currently going to buy Australian Classic Hornets. You know, the ones which have been flying for 30 years. The Super Hornets are ours.

Maybe if the international situation deteriorates, they will decide to buy the F-35.

- I think Japan is in a different situation than the others. They are right next door to China and Russia (both pursuing their own 5th generation fighters) and will need to a greater degree defend their own interests without the help of the United States. They aren't a partner in the F-35 program yet want develop their own aviation/defense industry capability. Here, the F-28.5 could make a lot of sense, and I could potentially see the USAF buying some of the aircraft since they have always wanted more F-22s. With that said, the Air Superiority 2030 Flight Plan seems to indicate that even the F-22 or F-35 are not good enough for what they are looking for post-2030.

My opinion for Australia, Canada, UK, United States:

- If greater range for a tactical fighter is needed, give the F-35 a variable cycle engine and external fuel tanks. The US can continue with PCA for the real range it needs.
- If greater A2A capability is needed, invest in better missiles such as Meteor, and/or something similar to an A2A version of the Israeli Stunner missile. 6 AAM internal in the F-35 will be here soon. The US can continue with PCA.
- PCA should be made available for export several years after it enters service.
- Drones, drone swarms, and so forth, should also be investigated.
- UK should reverse brexit and attempt to accelerate the European 5/6th generation fighter (my pipe-dream).
- If Japan proceeds with F-28.5 then these nations could buy in after significant F-35 deliveries.

It's not that I want to the protect the F-35 at all costs, it's more like I don't want to restart F-22 or F-22 clone production at any cost. Imagine if the F-15 had gone out of production in 1980. Then imagine in 1985 they decided to build another aircraft half-way between the F-15 and F-16, yet significantly more expensive than the F-16, potentially death spiraling the F-16, delaying the F-22 a decade, and halving the number of aircraft procured.

And there seems to be this idea that if the F-22 were available for export, everyone would buy it, but proponents of this rarely actually talk about why they would buy it, it's just an implicit assumption.

a reply to: thebozeian

a reply to: mightmight

Banned from export, banned funding to promote export, the end result is the same. There was no way to export the F-22 to anyone, even close allies.

a reply to: Zaphod58

I realise that America is still mindful of the F-14 being used by Iran (and its advanced systems being handed over to the Soviets). But I would imagine that with what is happening with China and the J-20, Japan and Oz could make a very convincing case for export permission to any sensible US Congress and President. It's a new world in ASIAPAC now, one where a Dragon is emerging far, far more powerful than the Soviet Union ever was.