And regarding the Indonesian involvement, looking back at those old articles..

https://web.archive.org/web/2014030...tkan-pemerintah-diminta-segera-memilih-desain
https://www.koreatimes.co.kr/southkorea/20140303/design-of-long-delayed-kf-x-still-in-debate
KF-21 could have been single engine with no hope to be upgraded into 5th generation, C101, the one heavily supported by the DAPA… The current design derived from C103 design was both worked by ADD Korea and Indonesian Aerospace. C103 got picked also because it is supported by Indonesia.
The single engine design supported by KAI (not DAPA) was the KFX-E otherwise also known as C-501. C101 was an earlier interation of design, that existed in parallel to C201 and was a twin-engined design. There was a proposed single-engined design of the next interation called C102E, but that was merely a concept. Current KF-21 is continuation of the iterative line of designs that continued from C101, 102, 103... all the way to C109, the last iteration before prototyping. You'll find a few posts regarding
these design iterations from few years ago on this thread.

Problem with C501 wasn't really the fact that their is no design headroom for latet upgrade into 5th gen, which seems much less relevant in current context (will get to that later), but the fact that it was based largely on design and technologies directly developed from KTX-II programme (which led to T-50), that had significant input from GD/LM. KTX-II programme had contract clauses that limited freedom of use of technologies and designs directly developed through the programme, and as such opting for C501 would have greatly jeopardised the goal of KF-X programme, which is to develop "(truly) indigenous platform" which ROKAF/Korean defence industry could toy around with as they wish.
 
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By the way, this enthusiastically excited guy is talking about the paralell development of Block III and the "6th generation fighter."
If I ignore the wild speculations from our "favorite sources" about possible cooperation with Saudi Arabia and the like, is there any truth to it?
I remember the heated debates among South Korean politicians before they secured funding for KF-X, and now the 6th generation program is running concurrently, albeit within a limited budget of ADD?
Ok, thanks, this makes sense.

In the long term, the ROKAF will need a replacement for the F-15K.
With experience gained from the KF-X program and its own indigenous powerplants they will have no reason to look abroad.

To add on top of the other reply from the previous pages, it seems like ROKAF made up their mind and are leaning towards a clean sheet design for the KF-16 replacement, rather than a full-blown 5th gen block 3, as in they are not interested in KAI's "KF-21EX" or "NACS stage II and III" proposals. So it is unlikely that there will be a parallel development of KF-21 block 3 and future Korean fighter jet that will follow-up on KF-21, that will replace the KF-16 fleet by 2040 as wel as F-15K going forward. Developing a clean sheet fighter to replace 60 jets doesn't make much sense, but for 140+60, the math adds up.

This doesn't mean that there will be no KF-21 block 3; there definitely will be one, since KF-21 will eventually need MLU during its service life and MUM-T is officially in pipeline, but a block 3 most likely would be something closer to Rafale Standard F5(and beyond) or Eurofighter LTE(again, and beyond), something that could be realistically be implemented to existing in-service airframes.

Now the question would be if such scaled-down block 3 woukd encompass something like retrofitting IWB, which seems doable, but it is also questionable as to how interested ROKAS is for such an upgrade.

Obviously, if a 6th generation next generation fighter programme is deemed too difficult/impossible to undergo, then there would be no other choice than to develop greatly modified 5th gen KF-21, a "Super Boramae" one might call, but at least as of now, a Super Boramae is unlikely.
 
To add on top of the other reply from the previous pages, it seems like ROKAF made up their mind and are leaning towards a clean sheet design for the KF-16 replacement, rather than a full-blown 5th gen block 3, as in they are not interested in KAI's "KF-21EX" or "NACS stage II and III" proposals. So it is unlikely that there will be a parallel development of KF-21 block 3 and future Korean fighter jet that will follow-up on KF-21, that will replace the KF-16 fleet by 2040 as wel as F-15K going forward. Developing a clean sheet fighter to replace 60 jets doesn't make much sense, but for 140+60, the math adds up.

This doesn't mean that there will be no KF-21 block 3; there definitely will be one, since KF-21 will eventually need MLU during its service life and MUM-T is officially in pipeline, but a block 3 most likely would be something closer to Rafale Standard F5(and beyond) or Eurofighter LTE(again, and beyond), something that could be realistically be implemented to existing in-service airframes.

Now the question would be if such scaled-down block 3 woukd encompass something like retrofitting IWB, which seems doable, but it is also questionable as to how interested ROKAS is for such an upgrade.

Obviously, if a 6th generation next generation fighter programme is deemed too difficult/impossible to undergo, then there would be no other choice than to develop greatly modified 5th gen KF-21, a "Super Boramae" one might call, but at least as of now, a Super Boramae is unlikely.
How does that view mix with potential KF-21 export, will KAI and the ROKAF support a more comprehensive Blk 3 if an export partner comes online as that takes the numbers greater than the original estimate?
 
How does that view mix with potential KF-21 export, will KAI and the ROKAF support a more comprehensive Blk 3 if an export partner comes online as that takes the numbers greater than the original estimate?
ROKAF would not be interested in a more extensive block 3 upgrade even if that means potentially more customers from abroad. For them, the most important thing is keeping the lifetime cost for the existing 120 Boramaes low, and if that is achieved, with or without and extensive upgrade, they wouldn't care much more.

As for KAI (and potentially other parties like MOTIR), I think it would be the other way around. They wouldn't be able to first develop an extensively upgraded block 3 in hopes of bigger export success and would only be able to fund it, if someone foots the bill. Now, closest answer to "who" is "no one", which is the reason I think KF-21EX/NACS-III is mostly dead. Sukhoi still hasn't been able to find any partners for Checkmate, and it's wishful thinking there would be any that will (partially) fund KF-21EX. Out of memory, I could only think of F-16 block 60 as any recent examples of customers footing the bill for the development of their own variant of an existing fighter, and the scope of investment required to make KF-21EX is just implausible.

I too am fairly surprised of such decision tbh, since I was expecting 5th gen block 3 to replace KF-16s (and most signs pointed towards that direction), while F-15Ks are replaced by an off-the-shelf heavy fighter around 2040, although I'm not sure what that aircraft would have been. Instead, it seems like ROKAF wants an indigenous 6th gen heavy fighter (a good hint is that recent model of KF-21EX that could house two 2k lbs guided bombs in the IWB) that will replace both KF-16s and F-15Ks as I've noted earlier.
 
I could only think of F-16 block 60 as any recent examples of customers footing the bill for the development of their own variant of an existing fighter,

Su-30MKI, Eurofighter Block 40K with P3Eb are other examples for customers footing the bill. So yes it is possible, whether it's realistic in this case is another question though.
 
Su-30MKI, Eurofighter Block 40K with P3Eb are other examples for customers footing the bill. So yes it is possible, whether it's realistic in this case is another question though.
You could also put the F-15SA in that basket. The Saudis spent a very large sum of money on converting the aircraft to FBW and opening up the outer pylons amongst other things.

I don't see a KF-21 export customer with the pockets deep enough to fund a significant capability enhancement of the aircraft, hence why I asked the question.
 
https://www.asiae.co.kr/en/article/2026031909371534562
Korean media that claims they got official information about export from ROK officials. According to this, it is confirmed that 16 KF-21 order from Indonesia as first export. They will be similar to ROKAF specifications and not the future Export versions.
 
https://www.asiae.co.kr/en/article/2026031909371534562
Korean media that claims they got official information about export from ROK officials. According to this, it is confirmed that 16 KF-21 order from Indonesia as first export. They will be similar to ROKAF specifications and not the future Export versions.
Wonder if South Korea get to claim back some of the development funding that Indonesia never paid or is still due to pay.

Assuming these will be Blk 2 jets, now to see whether the Philippines Air Force jumps on as well.
 
Assuming these will be Blk 2
According to the information shared by YONHAP NEWS, the KF-21 that Indonesia will receive is the Block 2 as expected with multirole, MRCA characteristics. In the future, it will have "commonality" in weaponry with our Dassault Rafale F4, for example, such as the MBDA Meteor beyond visual range air-to-air missile (BVRAAM), and possibly with the AIM-120 AMRAAM on the F-16.

whether the Philippines Air Force jumps on as well.
About that…

View: https://x.com/bworldph/status/2034121365469728938?s=61
 
I think that depends on the combat radius of the KF-21. The PI is a pretty "tall" country north-south.
You don't fly your fighter jet all the way from top to bottom of the country... PAF has bases all over and the KF-21 is going to have longer range than the F/A-50 so would work well for them.

PhilippineAirForce_AirBase_map-en.svg


The two main priorities are China incursion and the MNLF and MILF down south.
 
The Phillipines should probably work on asset dispersion. They are very vulnerable to BM and drone strikes. They rely on US investments in their radar systems and lack localized radars for self defense from either threat. KF-21 does nothing to strengthen these weaknesses.
 
So more than initial 48 units ?
The initial commitment is for 16. It may be a while till they consider more than 48. It also depends on whether their Kaan desire wanes and they top up with even more Rafales.

The Phillipines should probably work on asset dispersion. They are very vulnerable to BM and drone strikes. They rely on US investments in their radar systems and lack localized radars for self defense from either threat. KF-21 does nothing to strengthen these weaknesses.
There is about a 1000 different things the Philippines need to do to strengthen their military but they have to start somewhere. They also probably shouldn't expect to ever be able to stop determined Chinese aggression on their own.
 
You don't fly your fighter jet all the way from top to bottom of the country... PAF has bases all over and the KF-21 is going to have longer range than the F/A-50 so would work well for them.

PhilippineAirForce_AirBase_map-en.svg


The two main priorities are China incursion and the MNLF and MILF down south.
Looking at it, I think you'd want like 4 bases for KF-21s. 2 on Luzon, Palawan and probably Rajah Buayan.
 
There is about a 1000 different things the Philippines need to do to strengthen their military but they have to start somewhere. They also probably shouldn't expect to ever be able to stop determined Chinese aggression on their own.
Well, both US and Russia are now firmlmy stuck in 3 day determined operations; you either prepare to fight a war, or you pretend to.
Economy ladder goes as Philippines>Iran>Ukraine>DPRK.

Iran, for example, spends mere percentages of what gulf nations spend on defence, yet not a single gulf nation even considered procuring capabilities to keep gulf open.

The problem with modern mil procurement in most of the world is it's detached from reality and effectively ritualistic. It most certainly is possible to make small effective investment into mil capability against that.
 
Now that the first production KF-21 has been ruled out of the factory I wonder how long it will be before the first RoKAF KF-21 squadron is stood up?
 
Now that the first production KF-21 has been ruled out of the factory I wonder how long it will be before the first RoKAF KF-21 squadron is stood up?
Most sources list IOC as 2028 which makes sense given KAI expect to deliver eight KF-21 production aircraft this year.

KAI said it plans to deliver a total of 27 aircraft this year, including eight KF-21 fighters and 19 FA-50 light combat aircraft.
https://defence-blog.com/south-korea-launches-kf-21-fighter-mass-production/
Given IOC is generally a limited set of capabilities with a squadron sometime in early 2028 feels about right.
 
Daym, EOTS with faceted housing planned for the KF-21?

I’m not seeing any real surface or panel refinement on the “5th-gen” KF-21EX, just belly IWBs, EOTS, and conformal antennas (which is honestly more than enough, impo). That would still result in a dramatic reduction in RCS compared to the “beast mode” it operates in today, but it wouldn’t be in the same proper VLO league as the F-22, J-20, F-35, J-35, or Kaan.

I think the KF-21EX (i.e., Block 2) and Su-75 are carving out their own niche in how they approach LOity; you get conformal arrays, EOTS, and even belly IWBs, but without the full panel treatment to keep maintenance, production, and development simpler. It’s a commendable, more sustainable approach especially considering how “Day 1/Week 1 stealth mode” is performing today.
 
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i would like to see EOTS on the KF-21 snne, that would mean no more external jamming pods being needed and would also mean that it would also lower the RCS as well.
 
I think the progress of South Korea's indigenous turbofan engine development may not be as rapid as expected unless it receives technical assistance from the United States. The same goes for Turkey.
 
I would not be surprised at limited major structural revision of the EX version or block 3.
There's already space for an internal bay, and I can see them adding the EOTS.. but redoing some of the paneling so there's more serration, engine changes, etc.. probably unlikely. The Koreans have indicated they'd rather spend more effort on a next gen design.
 
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