UK-Japan-Italy Global Combat Air Programme (GCAP) Speculation & Discussions

[Rhinocrates]

Oh....Delta III !

Fairey's revenge?

Indeed, especially from this angle. Art by Keith Woodcock, for Tony Buttler's British Secret Projects: Jet Fighters Since 1950.

 

[Scott Kenny]

Avro Vulcan Mini-Fighter. Going with basically a delta wing (F-102/F-106 with thrust vectoring), interesting, needs two more elevons? If this is the final configuration, its an interceptor? Nice looking jet. Would be nice with all-moving vertical tails (e.g. NATF-23).

Well, I'm pretty sure that they're deliberately trading WVR maneuverability for better stealth, so I guess you could call it an interceptor in that sense.

And huge wings for lots of fuel to be able to fly from London to Moscow and back.

It's a very different creature from the FCAS, which is constrained by the requirement that it can be carrier based, leading to smaller size/weight and therefore range and payload. I don't mean to say that one is inferior, but that their roles are overlapping less as time goes on.

Agreed. If France is using the same size EMALS as the USN is, that limits their MTOW to around 90,000lbs/40 tonnes. Though the other part of that equation is the arresting gear, which seems to max out at ~55,000lbs/25 tonnes landing weight. And Landing Weight includes enough fuel for at least one go-around plus all the missiles carried, so your aircraft weight limits end up more like 40 tonnes MTOW and ~20 tonnes empty. And of course the elevator dimensions limit the max size of the airframe, but I expect the French elevators to be more or less the same size as the USN.

Note that the Advanced Arresting Gear on the Ford-class isn't said to be able to take any heavier weights than the Arresting Gear on the Nimitz-class, but rather is able to stop much lighter aircraft like UAVs safely in addition to safely stopping the existing heavy aircraft. The older arresting gear stops light aircraft too quickly, because it's set up to stop heavy jets.​

While I'm fully expecting GCAP and NGAD to be roughly the size of an F-111, some 110,000lbs/50 tonnes MTOW, and still aiming for 45,000lbs/20tonnes empty. Yes, fuel fraction of about 55%.

 

[FighterJock]

So how much fuel would the production GCAP/Tempest carry in comparison to the F-22? Not including external fuel tanks obviously.

 

[Scott Kenny]

So how much fuel would the production GCAP/Tempest carry in comparison to the F-22? Not including external fuel tanks obviously.

Assuming that "London to Moscow and back" mission, we're talking a 5100km range at the minimum (following a great-circle route). Add possibly another 2500km for combat, but I suspect a stealthy BVR interceptor/assassin won't need as much wild maneuvering, with associated throttle jockeying and increased fuel burn. So let's say a total range of about 6500km.

An F-22 has a clean all-subsonic range of 1100km on 8200kg of fuel, and a 185km-supercruise range of only 850km. For simplicity I'm going to work off the all-subsonic. I just can't grok the partial-supercruise bits well enough to make a good estimate while including some supercruise time.

Assuming similar fuel consumption to the F-22, we'd be looking at a capacity of some 49,600kg of fuel for the GCAP(!).

I don't believe that's reasonable, since I don't believe that the GCAP will weight more than 50,000kg at MTOW. I think we'd be looking at no more than 25,000kg of fuel for that MTOW. Yes, that's a high fuel fraction, but AAMs are light (even 10x Meteors+2xASRAAM ends up under 5000kg) and doubling all the dimensions means internal volume increases 8x. So the GCAP engines will need to burn half the fuel of an F119 in order to pull that trick off.

 

[Scott Kenny]

If this were solely the UK's Tempest project, there would be no issue.
However, GCAP is a joint initiative involving the UK, Italy, and Japan, with Saudi Arabia expressing purchasing interest.
Therefore, British requirements cannot be simplistically equated to those of Italy, Japan, or Saudi Arabia.

While true, but the UK is not going to accept much less range than that London to Moscow and back. Japan also wants range. Italy wants loiter time, which equals range. Saudi? who cares, they get whatever the UKIJ Primes design.

 

[timmymagic]

The range the UK will want at a minimum will not be London to Moscow....

It will be to launch from Lossie, go 1,000km into the Norwegian Sea and loiter for 4 hours before flying the 1,000km back...

That also tallies with what the Japanese will want....the ability to do a CAP from Kasuga AB to Taiwan, Senjakus, Iwo Jima or to push east from Misawa AB deep into the Pacific to protect SLOC's from H-6....or north from Chitose up the Kuriles.

That range would also allow them to cover all of North Korea with a full weapons load, without using tanker support...

The UK and Japan's range requirements will be exactly the same...

For Italy it means they can cover most of the Med...and reach into any North African country they want...

 

[Dolgoth Sepk]

The range the UK will want at a minimum will not be London to Moscow....

It will be to launch from Lossie, go 1,000km into the Norwegian Sea and loiter for 4 hours before flying the 1,000km back...

That also tallies with what the Japanese will want....the ability to do a CAP from Kasuga AB to Taiwan, Senjakus, Iwo Jima or to push east from Misawa AB deep into the Pacific to protect SLOC's from H-6....or north from Chitose up the Kuriles.

That range would also allow them to cover all of North Korea with a full weapons load, without using tanker support...

The UK and Japan's range requirements will be exactly the same...

For Italy it means they can cover most of the Med...

Is your battlefield assumption that the UK is independently confronting Russia in the North Sea, while Japan is independently confronting China in the waters off Taiwan, without U.S. involvement?

 

[Scott Kenny]

To defeat Russia, simply going from London to Moscow isn't enough – one would need to make a round trip from London to Komsomolsk-on-Amur. But if the goal is merely to trigger nuclear war, a strike from London to Paris would suffice.

Why TF is the UK fighting Russia alone?

Launch out of Tokyo if you need to hit Komsomolsk-on-Amur, that's only a 3500km round trip. Launching out of Elmendorf is more like a 9000km round trip, you're going to need to hit the bases on Kamchatka first. So the US would probably roll a couple of carriers within range and let fly.

But how many bases are east of the Ural Mountains? Vladivostok, Komsomolsk-on-Amur, 3? bases on the Kamchatka Peninsula...

The range the UK will want at a minimum will not be London to Moscow....

It will be to launch from Lossie, go 1,000km into the Norwegian Sea and loiter for 4 hours before flying the 1,000km back...

Depending on the loiter speed, that will still be a range of over 4000km. If loiter speed is 500kph, that makes a mission range of 4000km plus combat plus reserve. If loiter speed is 750kph, that's a mission range of 5000km plus combat plus reserve. I'd be surprised if loiter speed was 270knots/500kph, that seems really low for a fighter.

So my estimate of 6500km including reserves (~5100km plus reserves) is still reasonable for desired range.

 

[zen]

Ok some be over obsessing over flying to Moscow and dropping bombs there to fly home.
No.
Flying close enough that stand-off missiles can fly the rest of way, is much more likely.

Besides at the current development of NATO, we're talking of flying from Poland and Sweden if not from Finland.

Whereas, what Lybia, and Syria showed was every drop tank reduces the ordinance carried and forces more hours of subsonic flight just to get weapons on target. Lots of fuel burnt for little outcome.

I was trying to suggest this over 25 years ago about the UK needing something like the Russian Joint Continental Bomber / Long-range fighter (701) concept to succeed Tornado.

 

[yeetmahboi]

Saudi requirements seems to be ignored here. Reminder: they have a HECK LOT of desert to cover for interception duty.

 

[Rhinocrates]

Saudi requirements seems to be ignored here. Reminder: they have a HECK LOT of desert to cover for interception duty.

Yes, it's clear that they'll be customers even if Japan continues to block them from being partners. Specifically, covering Iran...

 

[snne]

And India is terrible about military procurement. Case in point, that time that Dassault, with almost no customers for Rafale, basically offered them a complete Rafale production line, complete with everything that that entailed.
Deal of the century... For India. It would have catapulted their indiginous aircraft industry forward by decades.

They thoroughly proceeded to fuck it up with idiotic demands. Fast forward a few years and then they bought a bunch of Rafale's at full sticker price in a busy market, instead of just building more themselves.

India is a shitshow, and anyone with any business acumen knows it.

Even putting the Rafale deal aside, had they gone ahead with the local assembly of the Su-57 and not demanded that Russia basically develop and finance an entirely new plane that they weren't going to use, they’d have been miles ahead by now.

For starters, they would have already operated 5th-gen jets and used the experience gained from this and the local production-assembly to boost the AMCA program in every imaginable way possible, making it arrive much sooner and more capable from the start.

People like to criticize the Su-57 for its inferior low observability compared to other 5th-gen jets, but they forget that it also comes with its own unique set of advantages. Additionally, its RCS isn’t as large as it’s often exaggerated to be.

 

[Arjen]

You’re the one who claimed that combat patrols can be conducted without aerial refueling.

I read that @Scott Kenny is spelling out what is needed to patrol 1000 km from base without refueling.
AI generated content is not helping your case.

 

[Scott Kenny]

Ok some be over obsessing over flying to Moscow and dropping bombs there to fly home.
No.
Flying close enough that stand-off missiles can fly the rest of way, is much more likely.

No, flying to Moscow escorting B-21s.

Saudi requirements seems to be ignored here. Reminder: they have a HECK LOT of desert to cover for interception duty.

And a fighter that can fly 1000km and then loiter for 4 hours will happily cover that requirement. Crud, the Saudis could probably get away with 500km and then get a 5 hour loiter out of it...

 

[eagle]

An F-22 has a clean all-subsonic range of 1100km on 8200kg of fuel

The subsonic combat radius is 595 nm / 1100 km.
All that with a fuel fraction of around 0.29.
The F-35A achieves a combat radius of 760 nm with a fuel fraction of 0.38. Assuming similar levels of fuel consumption, GCAP would require a fuel fraction of around 0.6 for a 1200 nm combat radius.
That is not doable for a fighter. For comparison, the Sukhois have fuel fractions of around 0.35, the MiG-31 and the F-111 around 0.42. But the F-22 is fuel hungry and the F-35 is ... aerodynamically challenged. So GCAP surely will be more efficient. But enough to achieve a combat radius of around 1200 nm? Probably not.
Maybe a 1000 nm radius with a fuel fraction of ~0.42 is possible.

 

[overscan (PaulMM)]

This topic is a free-for-all discussion topic on UK-Japan-Italy Global Combat Air Programme (GCAP). News should be posted to https://www.secretprojects.co.uk/th...combat-air-programme-gcap-news-analysis.40657

 

[eagle]

I think we can do better than F111.
VG takes up volume, and TF30 turbofan's s.f.c through the envelope wasn't that brilliant.

Not that easy I'd say. When the F-111 was turned into a fighter (F-14), the result was somewhat lighter, but it also lost nearly half the fuel.
Now try it without VG and carrier related reinforcments you might say. OK, but you have to add stealth and internal weapons... The F-22 and the F-14D are about the same weight.

Regarding SCF, the numbers I have for the TF30-PW-100 are much lower than say the F110-GE-100: 0.667 vs. 0.745.
Pretty hard to beat for a modern day fighter engine.

Btw. the FB-111 with an even better fuel fraction of around 0.45 manages a ferry range (clean) of 3033 nm. As a rule of thumb, A/A radius is about one third of ferry range.

The closest numbers for a fighter I could find are for the F-15C with CFTs. 840 nm combat radius with a fuel fraction of 0.4. Area intercept mission, so hi-hi-hi and no loitering.

Which leads me to believe that 1000 nm radius is a real challenge for a fighter, let alone 1200 nm.

 

[zen]

Actually I've stumbled of TF30 s.f.c figures and the variability of it quite interesting.
Your 0.667 is under particular conditions at lower altitudes and speeds.
Up high and fast the figures even go above 0.8

I suspect all turbofans have this feature.

 

[overscan (PaulMM)]

Regarding SCF, the numbers I have for the TF30-PW-100 are much lower than say the F110-GE-100: 0.667 vs. 0.745.
Pretty hard to beat for a modern day fighter engine.

Bypass ratio of TF30 is about 1 I think, so despite its age its quite fuel efficient in subsonic cruise.

 

[overscan (PaulMM)]

Actually I've stumbled of TF30 s.f.c figures and the variability of it quite interesting.
Your 0.667 is under particular conditions at lower altitudes and speeds.
Up high and fast the figures even go above 0.8

I suspect all turbofans have this feature.

All engines vary in SFC with height and speed.

 

[Combat-Master]

According to the Financial Times, Italian defense firm Leonardo is close to an agreement on a production partnership with Baykar.

Sources with knowledge of the talks between Baykar and Leonardo said the two companies were set to sign a memorandum of understanding next week that outlines the terms of a joint venture that could significantly increase Europe’s UAV production capacity. Baykar is one of the world leaders in the production of AI-enabled UAVs.

Leonardo is part of a trio of defence giants, along with Britain's BAE Systems and Japan's JAIEC, involved in the development of a sixth-generation fighter jet under the GCAP programme. JAIEC is jointly funded by Mitsubishi Heavy Industries and the Japan Aerospace Enterprises Association.

Mitsubishi and BAE Systems demonstrated drone models that could be integrated into GCAP in October.

Although the details of the Italian-Turkish partnership have not yet been clarified, the combination of Leonardo technology and Baykar platforms could lead to the development of a high-tech unmanned aerial vehicle capable of operating on the sixth-generation platform.

Thanks to this partnership, Baykar will have the opportunity to expand into the European market, which it has been targeting for some time.

https://twitter.com/x/status/1894731958875250749

View: https://x.com/SavunmaTR/status/1894731958875250749

 

[djpowell1984]

Canada turn away F35, so we should offered them GCAP as i think GCAP is great choice as long range as Canada big airspace so can long range patrol and stealth, fast that F35.

maybe we offered them temparoy EF or Gripen for short term like loan short term for if Hornet Retired until GCAP ready for them...

maybe Portugal too as open sea around them too so can long range patrol or single engine SAAB 6th generation.

 

[kqcke for you]

Canada turn away F35, so we should offered them GCAP as i think GCAP is great choice as long range as Canada big airspace so can long range patrol and stealth, fast that F35.

maybe we offered them temparoy EF or Gripen for short term like loan short term for if Hornet Retired until GCAP ready for them...

maybe Portugal too as open sea around them too so can long range patrol or single engine SAAB 6th generation.

Well how long can the Hornets even fly ? Afterall first F-35 in 2026 and full fleet around 2034 is quite hard to match for GCAP. Because if GCAP has no delays we see the first one not before 2035 and assuming same time for delivery the last GCAP wont be there before 2043. That said Hornets life IS only prolonged to 2032 and i doubt they can get another 11 years out of it. I mean then they would fly for close to 61 years so some any interim fighter would need to come now to be economical so some activ T2/T3 would make sense but that would mean someone has go build more new EFs and those second hands probaly aren't enough to fund that.