Japanese next generation fighter studies pre GCAP (aka i3, F-3)

red admiral said:

F-35 rear fuselages are made in Salmesbury and shipped all around the world to be assembled. Same with almost all Airbus and Boeing products. It's not optimal but is definitely feasible.

I realise that, but the F-35, Boeings and Airbuses are multinational products with multiple production lines and widely-spread supply chains and have had volume production to ramp up the efforts to a sustaining level. An Anglo-Japanese fighter (excluding possibility of SAAB joining etc.) would be a smaller pool with fewer airframes (~250 airframes max?). BAE Systems and Leonardo would probably seek airframe share as would the Japanese companies, so two assembly lines would be most likely.
Yes choices between how much to spend in total Vs how much to spend in your own country.
Yep. Japan is too scared of Trump to consider working with the UK.

Not a long term plan, more a lack of a plan.
Harrier said:
F-22 derived new fighter, with Japanese engines?

What's being talked about there is not a joint US-Japan programme, but a wholly Japanese funded one, led by LM and supported by Japanese companies. Is that construct, but basing elements from F-22 really cheaper than partnering with another country for a new build aircraft that actually meets Japan's needs?

You've got to love LM's marketing guys coming up with a proposal saying "give us $20-30bn and we'll develop a new fighter for you". Great business if you can get it.
Meh, if the Japanese were serious about an air superiority aircraft, they would have approached Northrop Grumman. Lockheed has a poor track record with aircraft post WWII except for 2 niche aircraft. It wasn't until General Dynamics paired with them that they got their act together on the ATF and they only won that by default of the USAF not wanting to give too much to NG. The F-35 isn't anything special except for the electronics and engine supplied by other companies. Even their ships suck, aka the LCS.
By now the basic F-22 airframe and any flaws to be corrected are well understood. For all that Northrop had an arguably better plane, it was not without it's flaws (the weapon storage), and we have no idea what other things would have popped up in series production.

Furthermore the F-35 has given Lockheed a HUGE amount of experience with more modern RAM and it's application, not to speak of the integrated sensor suite.

You can put them down for all you want, but when it comes to stealth fighters they undeniably have the most experience of any company... In the world.
Airplane said:
Meh, if the Japanese were serious about an air superiority aircraft, they would have approached Northrop Grumman. Lockheed has a poor track record with aircraft post WWII except for 2 niche aircraft. It wasn't until General Dynamics paired with them that they got their act together on the ATF and they only won that by default of the USAF not wanting to give too much to NG. The F-35 isn't anything special except for the electronics and engine supplied by other companies. Even their ships suck, aka the LCS.

Remarkable, almost nothing in that paragraph is actually true or accurate.

As mentioned by other contributors like or loath them Lockheed Martin have unrivaled experience with low observatory combat aircraft (especially those below strategic bomber size).
I know it's not going to happen but if the US were to signal they'd purchase some of these modernized F-22s and pay for a share of the development I wonder if Japan would find that offer more appealing. Yes the final product would have less systems built/designed in Japan than a new design but they'd be a lot less risk involved and lesser development costs.

What are the odds companies other than Lockheed will offer to work with Japan on a whole new design? Seems like it would be a good opportunity for any of the big US three while the USAF is still deciding what they want from PCA and the USN fumbles F/A-XX somehow.
OK, Here is some recent news.

View: https://i.imgur.com/ck9m6ZK.jpg

View: https://i.imgur.com/nCx6rB0.jpg

XF9-1, a prototype engine for future fighter, proved its predictive thrust performance of more than 15 tonnes(3,5000lbs) with AB and more than 11 tonnes(2,7000 lbs) in dry. Will be tested further until late 2019 and advance to develop a more enhanced engine with 17 tonnes(3,7000lbs) (AB) thrust by 2023.

The second picture is taken by one of a member of the House of Councilors(upper house of the Japanese Diet) during his visit to IHI Corporation. He wrote on his blog that according to one of an engineer who works on there, this engine generates several times more electricity than F-22's F119.(http://nakanishi-satoshi.hatenablog.com/entry/2018/09/15/095121)

View: https://i.imgur.com/WNR6sS3.jpg

View: https://i.imgur.com/uNfw0vu.png

View: https://i.imgur.com/MTw7d9C.png



JASDF Air Development and Test Wing's XF-2 501, equipped with the prototypes of advanced high-speed data link, tile-type GaN AESA radar(ATLA claiming it's 1.5 times longer detection range than foreign 5th gen fighter's radar(maybe refers AN/APG-81?)) which has electronic warfare capability, and high-resolution QDIP(Quantum Dot Infrared Photodetector) sensor on a modified anti-ship missile, flew first on October 31, Japan standard time.

It will demonstrate the sensor fusion capability and the ability to share the integrated information between the air and ground with a T-4 trainer that also incorporates the data link system.



Actual scale IWB prototype and the central body made of CFRP+CNT materials with integrating adhesive molding technique(this makes riveting obsolete so reduce the weight and simplify the process.)

JNAAM will have Ka-band GaN AESA radar made by Mitsubishi Electric as its seeker(AAM-4B has Ka-band AESA seeker but it isn't made of GaN). FYI, watch this video about the advantage of Ka-band frequency as a missile seeker by MBDA(https://www.youtube.com/watch?v=JG2B-Ot9SL4)

According to the Japanese MoD, its first launch test will be carried on a U.K. fighter to reduce the cost. (Meteor構成品を活用するとともに発射試験の母機に英国のMeteor搭載可能機種を使用することで研究経費及び期間の効率化を図る計画としている。)

JNAAM prototype will be rolled out from 2018 to 2022 and the trial period is from 2021 to 2023.(事業実施の時期平成30年度から平成34年度まで研究試作を実施し、平成33年度から平成35年度まで試験を実施する予定である。)

Source : http://www.mod.go.jp/j/approach/agenda/meeting/seisaku/sonota/25kai_shiryou2.pdf page.17

The Japanese MoD also looking to integrate this missile on F-15MJs which will be further upgraded with AN/APG-82(V)1 radar, new mission computer and self-defense system and the reinforced body that allows equipping twice the number of air-to-air missiles etc.

Source :

-Below two images are from Fuji TV's programme called 'Weekly Security'. They asked directly to JASDF Air Staff Office about the further upgrade plan for F-15MJs and got the answers of the exact model of radar and etc.
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With Glue, Japan Uses Composite For Fighter Substructure
Nov 20, 2018 Bradley Perrett | Aerospace Daily & Defense Report

TOKYO—Japanese engineers, working on replacing fasteners with glue, are applying composite to combat-aircraft substructure as well as the skin.
A full-scale mid-fuselage, now under strength testing as part of the technology acquisition effort for Japan’s Future Fighter program, incorporates the arrangement. The test specimen is built up from modules in which composite skin is glued to composite frames and beams that are themselves joined to each other with adhesive.

Evaluation is not complete, but so far no major problem has arisen, says an official of the defense ministry’s Acquisition, Technology and Logistics Agency (ATLA), which is undertaking the work in partnership with Mitsubishi Heavy Industries (MHI). Testing is due to end on March 31, 2019. But the technology is difficult, says the official, suggesting more time may be needed.

In the analysis of Japanese engineers, a key factor preventing general use of composite substructure has been the intolerance of the material to mistakes in drilling, which results in a high scrap cost. But the problem almost disappears if glue is used instead: very little drilling is required.

The specimen mid-fuselage has been built to one of the concept designs that ATLA prepared for the fighter, which would be a large combat aircraft entering service in the 2030s. The government is considering alternatives to an indigenous program, including joint international development—but an aircraft developed with another country could still use know-how that Japan had accumulated in anticipation of going alone.

MHI built the mid-fuselage in fiscal 2017. It is 8.6 m (28.2 ft.) wide and 5.2 m long. This test specimen follows a smaller glued-composite structure that was previously evaluated. Thanks to the bonding technology, the mid-fuselage is a little simpler than might be expected if it had been built with the usual technology: it has fewer structural elements.

The specimen has been taken to limit load, the highest intended for flight, but not yet to ultimate load, which is 50% greater, the official says, speaking at an ATLA technology seminar.

Engineers are looking for failure in the adhesive and in material close to joints. So far they have seen none, the official said. As ATLA has previously described, the assemblies are made of elements cured separately in autoclaves and bonded under pressure.

Apart from creating the opportunity to use more composite, bonding creates a large direct saving in weight: Compared with fasteners, the glue has little mass, and the parts do not need to be thickened around holes.

ATLA estimates the structure under test weighs 10% less than it would if it had been made with fasteners and the composite-metal ratio of the MHI F-2 fighter, itself a step forward in use of lightweight materials. The agency will not say how much weight is saved within the composite alone.

The mid-fuselage still needs metal in the belly area, to absorb complex loads from the landing gear, a task for which composite is not suited. The weapon bay, also in the lower part of the mid-fuselage, also needs to be made of metal.

Fatigue testing of the Japanese technology would be desirable but has not yet been funded. Such work would have to be done with a smaller piece, to hold down the size and cost of a refrigeration facility that would be needed, the official says.


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Would you also make a copy of this article, please? I can't access the full article because of the paywall.

Here are some images of the presentation about XF9-1 engine by ATLA on November 13.

View: https://i.imgur.com/bddQFrj.jpg

View: https://i.imgur.com/vViRVO7.jpg

View: https://i.imgur.com/eTHkS8y.jpg

View: https://i.imgur.com/Pz5jMFU.jpg

View: https://i.imgur.com/rEnJ9Hb.jpg


The Japanese fighter engine prototype, which is 30% smaller than F110 and generates more electricity than F135(160kW) with world's highest turbine outlet temperature(1,800℃), has surpassed F119 in thrust performance according to the last image. The final goal is the performance similar to F135, with AB thrust up to 20 tonnes and at least 14 tonnes in dry thrust by 2030.
Ares said:
Would you also make a copy of this article, please? I can't access the full article because of the paywall.
We are not posting AWST stuff beyond paywall here...
lastdingo said:
Ares said:
(AAM-4B has Ka-band AESA seeker but it isn't made of GaN)

Do you have a source for this? This is a millimetric band, it should provide very little range. Maybe too little range given the tiny radar antenna and the purpose.


From this link, find this line, II 技術研究開発 8.第3研究所 (II Technology Research and Development 8. Third laboratory), open the PDF and look at the page 278~279
Let me translate. By Google translator, there may be some mistranslated phrase.

View: https://i.imgur.com/UY4JCt4.jpg

View: https://i.imgur.com/eMVmuED.jpg

View: https://i.imgur.com/LXj6s6g.jpg

ウ 電波誘導制御装置
3 Radar Guidance Control System

(ア) 目的
(1) Purpose
小型地対空誘導弾に適用可能な電子走査方式の小型電波誘導制御装置, 高度な信号処理により目標追尾性能の向上を図った電波ホーミング空対空誘導弾用アクティブ電波装置, 全天侯運用可能な小型対空誘導弾において捕捉 ・ 追随性能及ぴECCM性能の向上を図るKu ・ Xバンド複合電子走査アンテナ要素、 誘導精度と 目標探知性能に優れたKa バン ドシ一ヵ実験装置を研究試作し, 開発の可能性を判断又は実現可能性を検討するための技術資料を取得する。
Electronic scanning type small radar guidance control device applicable to small ground to air induced missile, all-weather radar homing aimed at improving target tracking performance by advanced signal processing active radar device for air-to-air guided missiles, compact size Ku · X band composite electronic scanning antenna element that aims to improve capture and follow-up performance and ECCM performance in anti-aircraft missile, research prototype of experimental device of Ka-band system superior in induction accuracy and target detection performance, acquire technical information for judging possibility or considering feasibility.

(ィ) 経緯及ぴ結果
(2) Background and results

電波誘導制御装置にっいての技術資料を取得し、 その成果は、 短距離SAM (改)、AAM-4、 新中SAM等の開発に反映されている。 また、 全天候性と耐妨害性に優れ、 髙分解能化が可能なミ リ波帯を使用し、対地用精密誘導武器の実現可能性を検討ずるための研究試作も実施し、 現在、 対地誘導弾の誘導装置と しての実現ヘ向けて研究途上にある。 さらに、 Kaバン ドシ一ヵ実験装置の研究試作にょる成果の一部は、 周波数帯城の異なるもののAAM一4のフォロ一アップにおいて、 低コスト ~高パフォ一マンスを実現する技術と して反映され、AAM-4 (改) 及ぴSSM一ー (改) にも反映されようとしてぃる。
Technical data on the radio wave guidance control device was acquired, and the results were reflected in the development of short distance SAM (reform), AAM - 4, New medium range SAM etc. We also conducted research prototyping to examine the feasibility of precision guided weapons for ground using millimeter wave band which is excellent in all weather and resistance to disturbance and capable of high resolution, We are in the process of research toward realizing it as an induction device. In addition, some of the results of research prototyping of the Ka bands experimental equipment are different technologies for achieving low cost to high performance in the follow-up of AAM-4 with different frequency bands It is reflected and is also being reflected in AAM - 4 (revised) and SSM - 1 (reform).

View: https://i.imgur.com/qqWyMaI.jpg

Ka バンドツーカ実験装置
Ka-band experimental device

View: https://i.imgur.com/HDHNVUz.jpg

Colored picture of it

Not only AAM-4(改) = AAM-4B but SSM-1(改) = Type 12 surface to ship missile also utilized this Ka-band AESA seeker.

PAC-3, Aster Block 1 NT, David's Sling etc., all advanced anti-air missiles nowadays using Ka-band millimeter wave for their seeker. Millimeter wave means extremely high frequency, which is difficult to jam, narrower beam means more detection range with higher resolution. This is why UK gov decided to work with us to develop next-gen air-to-air missile.


And for JNAAM, ATLA already finished the prototype of seeker antenna and guidance system which is 1.5 times more improved than AAM-4B on target identification and tracking capability by significantly reduce the S/N(Signal to Noise) ratio with the unique prediction based tracking & missile guidance technique. ATLA said they successfully shot stealth targets down in the simulation.
Technology eliminates disadvantages. As the Technical Research and Development Institute of the Japanese Defense Agency suggested, it's 全天侯(all-weather, all-circumstance).

Interference by weather can be canceled with high power output RF device. Ka-band frequency has recently become widespread in the advanced missile manufacturers and the U.S. also started to develop their own Ka-band AESA seeker.

View: https://twitter.com/MIL_STD/status/1049825288916520960
lastdingo said:
Ka band is also where there's a high attenuation of the radio wave due to H2O in the atmosphere.


True but, this homing seeker is meant to operate at very last moment and search small area. that lessen the power aperture product requirement.

Trump pressures Tokyo to choose US fighter jet over rival BAE
Japan is looking at UK company to develop an alternative to its F-2 aircraft


A deal to replace Japan's F-2s would be worth tens of billions of dollars © AP

Demetri Sevastopulo in Washington and Robin Harding in Tokyo 3 hours ago

The Trump administration is pressuring Japan to choose a US defence company to develop jointly a replacement for its F-2 fighter jets as Tokyo considers a British alternative to cut its reliance on American weapons.Pentagon officials have stepped up talks with Japan amid concerns the US could lose out to BAE Systems, the UK defence contractor developing a sixth generation Tempest stealth fighter, according to three people familiar with discussions about the F-3 programme.Tokyo wants to replace its F-2s when they retire from around 2035 and plans to start development next year, in a deal that would be worth tens of billions of dollars. It is considering three options: collaborating with BAE; working with Lockheed Martin, the US maker of the F-22 and F-35 jets; or developing a plane domestically.The US air force is worried that choosing a UK fighter would create interoperability issues. American officials are also concerned that opting for a British jet would anger President Donald Trump, just as Washington and Tokyo are engaged in tough talks about how much each should pay towards maintaining their alliance.The US stunned Japan in July when it said it would request a fourfold increase to $8bn when the allies renegotiated the “special measures agreement” that determines their contributions.

Eric Sayers, a Japan expert at Beacon Global Strategies, an advisory firm, said Japan would be making its fighter jet decision just as tensions “could be boiling” over cost sharing. “Tokyo should be able to make its own sovereign decision about which option . . . to replace the F-2,” he said. “But President Trump has a record of taking a transactional approach to alliances and the Abe government should not expect he will view the special measures agreement negotiation and this large procurement decision as separate.” Mr Trump has made Japan — and his own military officials — nervous by threatening to withdraw troops unless Tokyo pays more. He has also frequently touted Japanese purchases of US weapons in his meetings with Prime Minister Shinzo Abe. Taro Kono, the Japanese defence minister, recently told the Financial Times that he was open to collaboration with a European programme such as Tempest, underlining the concerns in Washington. One senior US defence official stressed that Japan should view interoperability as “a significant factor” to consider. “Because of the importance of the alliance and the current security dynamics in the region, we would obviously prefer the Japanese work with the US on their future fighter programme,” the official said. “There are a few examples of going it alone that have taken too long, cost too much and not done much for interoperability.”

Michael Green, a former top White House official with close ties to the Abe administration, said the Pentagon’s lobbying was paying dividends after Tempest gained early momentum. “The US government is organising itself around a campaign for an American fighter. And in the Japanese government, some of the big pieces have shifted so that the momentum is shifting towards a capabilities-based decision which would benefit a design based on an already existing US platform,” said Mr Green. “But it is not over. The momentum could shift back since there are lots of variables.” Japan has long dreamt of building a domestic aircraft to match its famous second world war-era Zero fighter. The project to build its own plane gained urgency last year when Mr Abe opted to buy 105 fully-assembled F-35s from the US. One Japanese executive said that had left local industry desperate for a new fighter programme to work on. The US has proposed jointly developing a fighter based on the F-35 and F-22. But it would limit the use of Japanese technology, resulting in a “black box” fighter with no access to the source code required for independent upgrades — something the Japanese air force would like and many lawmakers consider essential to sovereignty. “The most important thing for a future fighter aircraft is capability,” said Itsunori Onodera, a Diet member and two-time defence minister. “Then there is data links, including to US networks. And then it is also necessary to have freedom to upgrade.” Mr Onodera said Japanese industry did not have the capability to go it alone and the cost per unit of building exclusively for the domestic market would be prohibitive. He added the similar timeline of the Tempest made collaboration with the UK a “reasonable possibility” but the decision would depend on capability, cost and the potential for upgrades. The decision will be up to Mr Abe, who will have to choose between independent technology and nationalist hopes or the US alliance and his prized relationship with Mr Trump.

Follow Demetri Sevastopulo and Robin Harding on Twitter: @dimi and @RobinBHarding
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Do we really need to post this in three different threads!? :mad::confused:
SK and Japan have very different strategic constraints. Think at the geography and casualties rate that you plan to impose on your enemy. SKAF is built to bleed its close-by enemy to death. JSDF is built to protect and project Japan interests over a vast area devoid of any basing support.

Very different objectives for a fighter program.
Personally I think Japan and SK should try to settle their differences and do more teaming arrangements. Next gen fighter and carriers come to mind.

won't happen with the current governments. You want a Korean right leaning government, and a Japanese left leaning government for that to happen the reason is

S.Korean left wing government tends to be more anti-Japan, more friendly to N.Korea, and a little bit colder to the US
Japanese right wing government tends to be more anti-Asia and pro-US

thus you need
S.Korean right wing conservative government thats more anti N.Korea and Japan/US friendly
and Japan left wing government that is more Asia-unity minded

Japan and S.Korea, under its previous governments, agreed to settle the comfort women issue with Japan paying. but the current S.Korea administration decided to re-open it up.

secondly I also think Tomcat is right in the sense that S.Korea and Japan are looking for different things. To me, S.Korea is a lot like Cold War West Germany in its defensive doctrine and equipment purchases, while Japan is more like the UK. one needs more rapid action stuff, the other needs more long range things.
I wonder how it would compare with the J-20 size wise, it certainly looks as if it is going to be a big fighter. :cool:
Hmmm... not sure where AvWeek sees a resemblance to Tempest in there (wing planform in very general terms perhaps, but that's rather tenuous) - it does have quite a few similarities to FCAS though (wing planform, tail configuration, rear end in general). Probably the closest likeness is actually one of its predecessors in the F-3 study however, the rather beautiful 24DMU iteration - the biggest difference is that the new design gets rid of the Su-57ish engine and weapons bay configuration.
Hmmm... not sure where AvWeek sees a resemblance to Tempest in there (wing planform in very general terms perhaps, but that's rather tenuous) - it does have quite a few similarities to FCAS though (wing planform, tail configuration, rear end in general). Probably the closest likeness is actually one of its predecessors in the F-3 study however, the rather beautiful 24DMU iteration - the biggest difference is that the new design gets rid of the Su-57ish engine and weapons bay configuration.

do you have the picture of the AvWeek variant?

ultimately I wouldn't put too much faith in the MOFA images as they used a lot of random CG in the past
the picture in that PDF looks a lot like 24 DMU. I really hope I am wrong though because 26DMU is pretty boring looking
and most of the 5th gen stuff out there (F-22, F-35, J-31, TFX, KFX, etc) all more or less look the same.

right now Japan is at 26DMU (unfortunately much more conservative looking)
and has already done the wind models and engine testing for it

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"我が国の防衛と予算(案)-令和2年度予算の概要-" P14

this blog is collecting F-3's imformation


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"我が国の防衛と予算(案)-令和2年度予算の概要-" P14

this blog is collecting F-3's imformation

Image from PDF is the same one already posted.


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