S. Korea’s New Stealth Fighter Design

Check out these pictures that Steve Trimble snapped of the latest stealth fighter design to hit the international market. They pics show Korean Aircraft Industries’ proposed stealthy next-gen fighter that was unveiled at the Seoul Air Show this week. South Korea plans to field the plane, dubbed KF-X, in the next nine years as a replacement for it’s Vietnam War-era F-4 Phantom IIs and F-5E Tiger IIs. Going from fighters that first flew in the late 1950s and 1960s to a stealthy design resembling some sort of twin-engined F-35 Joint Strike Fighter, as Trimble puts it, is quite the leap. In addition to KAI, Eurofighter is also bidding a design for KF-X. In an example of how stealth fighters will be all over the place by the 2020s, Indonesia is already a partner in the program and F-35-buyer Turkey may join the KF-X effort soon. Seoul wants the KF-X to carry locally developed air-to-air missiles, guided bombs and anti-ship missiles. That’s right, a new fleet of stealth jets with new weapons in just nine years.

Keep in mind that South Korea is also looking at buying 40 to 60 Sukhoi PAK FAs, F-35s or F-15SE Silent Eagles under its F-X program which is supposed to kick off next year.

Click here for more info on the jet.

  • blight

    Definitely ambitious. New weapons, new aircraft, and a 5B budget?

    If they can get it done, maybe we should figure out what they’re doing right and what we’re doing wrong. Then again, we can still pitch our -35B’s for the Dokdos, and if you have the -35B you may as well add the -A for your ground troops if you’re in the market for a new air force.

    • ospreyluvr

      It may be cheaper for them to buy this KF-X instead of the F-35A. Then again, having all your planes built off the same platform makes maintenance simpler. Has ROK had their very own plane in the past few decades?

      • blight

        KT-1 and T-50 Golden Eagle. Possibly others.

      • wqedsd

        even countries who are considered close allies to the US need to consider avoiding dependence. who knows what will happen in politics.

    • Tad

      I think that what they’re doing right is they have a broad and growing industrial base with all the associated technical and engineering expertise that go with it. The US has a declining base and so is left with few people having the technical, engineering, manufacturing and associated administrative know-how.

  • ospreyluvr

    Looks like a F-35 with hints of the F-16. I like it! I hope that ROK goes with either the F-35 or F-15SE for the F-X program, but it is great to see them working on developing their own stealth aircraft. I doubt the aircraft can compete with the likes of the F-35 or F-22, but it could be a cheap stealth alternative to the F-35. Looking forward to hearing more from this craft.

  • Zap

    Turkey have already said they won’t take part unless they are a equal partner

  • tiger

    All those years of Selling Hyundai’s is paying off….
    Long term we seem to have a trend of 3rd tier nations like Iran, Pakistan & now South Korea domestically producing jets. Leaving the US & Mig with nobody to sell to.

  • Dfens

    Either they plan on these fighters going on a one way trip toward the enemy and not coming back, or they figure they’ll be so badass they won’t leave any threats behind. I’m thinking the former instead of the latter. But what the hell, you can probably buy a dozen for the price of an F-35.

    • melcyna

      somehow i don’t think a country who is still in a state of war and has one of the most unpredictable and dangerous neighbor will do a project that doesn’t give a solid result.

      • Dfens

        Too bad politics doesn’t trump physics then, isn’t it? Maybe they can do like the flying taco chip (A-12) was supposed to and never fly directly away from the enemy. It’s just as great an idea now as it was then.

        • melcyna

          or a second possibility would be that they have internal bay alright, but still can mount external payload and the model shows both?

          who knows, i mean technically since the country would most likely want 1 multi role fighter if possible that’s not too far fetched.

          internal payload only for the strike, then the following sorties or planes can be mounted with external payload for maximum ordnance delivery once there is a safe corridor.

        • melcyna

          either way though, for a country that’s under constant threat and have been ‘attacked’ even in this stalemate condition several times now, whatever planes come out of this would have to be combat ready since aside of massive artillery the NK also have very dense air defense.

  • Joe

    First impressions can be wrong, but this sort of reminds me of the Yak-38 Forger, the Soviet vertical take off fighter that could only carry 2200lbs of weapons. Sure it’s stealthy, but what good will that stealth do if it can’t carry any weapons behind enemy radar?

  • Lance

    Looks more like a mini F-22 than a copy of a F-35. good for ROK. But do they have the resources to build such a complex thing as a stealth fighter? Other nations tried and failed to build such planes have to wait and see.

  • brianckramer

    At least THEY were smart enough to put two engines in it… F35?

    • ospreyluvr

      One engine can be just as good as two. F-16 anyone?

      • brianckramer

        yeah…not really…


        “The F-16 is known in Air Force circles as the “lawn dart” for its tendency to plunge back to Earth when its single engine flames out, and in most years, engine failure causes more accidents than any other factor.”

        “In the late 1990s and the early part of this decade, engine problems caused the number of F-16 Class A crashes to spike to as many as 18 in one year”

        • XYZ

          Still one of THE best fighters ever made, so…

          In any design, there are trade-offs that must be made. I’m not disputing your figures or logic, I’m just saying having another engine sacrifices in other areas.

          • brianckramer

            Like what? All of our bombers and current gen fighters have multiple engines except f16/f35.

            What’s the tradeoff? What’s the benefit of one engine over two? Don’t say cost.

          • crackedlenses

            Weight, perhaps? My understanding is that the F-16 was a product of the light-weight mafia….

          • mike j

            LOL… Whatever you do, DON’T say the thing that it is! Going to have to disappoint you, sorry.

            Col. John Boyd was the leader of the “fighter mafia.” He was fond of saying “You pay for airplanes like you pay for potatoes, by the pound!” Two engines _might_ halve the chances that you lose the plane to engine failure, but it doubles the chances of engine trouble. It adds weight and complexity that must be compensated for, and ultimately must be paid for. I said ‘might’ because you can have a situation like an engine fire that destroys the plane before you can recover it.

            The point of the light weight fighter was an exceedingly inexpensive airframe that was nonetheless more advanced in every way that mattered to the air-to-air fight, as the fighter mafia saw it. The airplane they conceived of was not the one we purchased with the F-16. Some will say that was for the best.

          • PMI

            @brian: What’s the tradeoff? What’s the benefit of one engine over two?
            — Fuel efficiency, weight & yes like it or not cost. Not only in the airframe itself but in the entire logistics chain. Only needing to support half as many engines in a fleet is a hell of a lot cheaper.

            ABC news non-withstanding the Viper hasn’t been referred to as the lawn dart since the early 80’s. Also only half of those 18 Class A mishaps in ’99 were engine related. The F-16 fleet has averaged roughly 2 engine related Class A’s per year over the past decade or so.

            @mike: “Some will say that was for the best.”

            —Yes radars really are good things to have! :D

  • Josh

    I can’t help but think all these new designs coming out of smaller countries are just 4th gen fighters Ina shiny new stealth lookalike body. The coatings,materials and tech needed for a truly stealth aircraft are immensely expensive. Plus electronics and an engine that’s capable of a good PtW ratio is a tall order for any military,especially a small one. I somehow see them buying F-15’s or F-35’s when this project runs over budget and behind schedule.

  • Josh

    FYI I’m not downing on the south Koreans,I feel all our allies should be striving for technology. But this is a very tall order. Best of luck!

  • Andrew M

    External weapons defeats the purpose of stealth, they should just maximize maneuverability and aerodynamics and call it a day

    • blight

      They’re designing new missiles too: so if they opt for stealth casings and stealth mountings, it might not be so bad.

  • jakoye23

    Have they even built a plane before? Seems kind of a reach to building a stealth fighter from scratch.

    I’ll log this one up as a “dream machine” that never sees the light of day.

    • FormerDirtDart

      Just a few. KAI built the KF-16, is responsible for 40% of the production & 25% of the assembly of the F-15K , they developed and build the T-50 Golden Eye. And, that’s just the supersonic fighter/multirole aircraft.

    • So?

      20 years ago Korean cars were junk. Where there is a will, there is a way.

  • Mastro

    Didn’t they just start making the T-50?

    Talk about ambitious-

    If Taiwan and India have had so much trouble with their indigenous programs- I’m a bit skeptical about this on-

    Maybe they are trying to mess with North Korea’s minds? They are really being left behind- isn’t half their airforce still MIG 17’s?

    • Hurrah

      I think South Korea is well aware that the problem with North Korea isn’t their airforce.

      It’s the unless amount of ‘stupid’ artillery, and a few nukes. When you consider that, it seems like the billions designated for a stealth fighter are a waste. Better be working on unbeatable CRAM and anti-ballistic missile technology and deploy them massively.

  • roland

    Just a taught while I am drinking my tea: Why wait nine years when they are already been threaten by North Korea 9 years past to present?

  • roland

    They (SK) should have bought our (USA) F-35B, F-22,F-18, F15 eagle or YF-23 for their country’s defense.

    • Tell us why?

    • blight

      I’m surprised you don’t advocate they buy both F-22 and YF-23 this time around. Bravo.

  • marvel

    Looks like the F-35, F-22, F-18 and Su-27 had a baby.

  • Tee

    Looks like the twin engine version of the Saab Stealth fighter the Saab and S. Korea went it to partnership with Indonesia to build. Here are a few links to testing of a 1:13 scaled demonstrator of a stealth fighter concept designed by Saab.

    I’m looking for the other links to the twin engine

  • Dan

    the first picture looks a lot like the xf-23 just without the triangular wings

  • Part of that new trade agreement with the USA I bet, eh? Maybe we are going to generate some income selling Stealth tech to S Korea. Bonus the increased military buffer against North Korea and China…Sounds Great! Lets see how their defense industry handles itself – what will they learn from the US…our groundbreaking technology or our greedy fatcats and politicians who allow Billions in cost overruns. Let the engineers lead the way, and S Korea could develop a thriving aviation industry. Good Luck!

  • Nick

    As others have said before, conformal weapons bays like SE. And centerline pod maybe? Could get out 3-6 missiles and then run?

  • Letsallbefriends

    At least it’ll come with a decent warranty.

    • EJ257

      Flying 600mph you’ll be surprise how quickly you’ll hit 100K miles ;)

  • oppervlakkig

    From above it’s like a F-16 with a huge rear end :P

  • Roland

    I guess with all this upgrades SK were pursuing, NK are still not move, simply because they knows the Chinese were in their back.

  • Michael

    I think they could probably pull it off. Realistically, it wouldn’t be up to the capabilities of the F-22 or the F-35, but I don’t think that is their goal. I think they are trying to build something comparable to the F-15 Silent Eagle (ok, it probably won’t have similar power to weight ratios though). Front the front, their design looks like it could be made to have a low radar cross section. They even have long angled air intake pathways, which significantly reduces reflection off the front turbine blades. I am assuming they will have non-metallic leading edges, similar to the F-117. No big secret, high-tech stuff there. Now, the rear turbine nozzles, on the other hand, are not low signature at all! And for the record, I am ignoring the fact that all of the armament is on external stores, another stealth no, no… It’s possible they could put an internal weapons bay between the cockpit and the engines? Due to the way the design pictures are, it would only be stealthy when attacking?

  • blight

    As long as it has the range to deliver a bomb to Pyongyang and return…

    Wonder if the United States keeps nuclear weapons in Seoul for this.

    • blight

      On a side note, what’s everyone’s opinion on their missile plans? Does the ROK make a number of indigenous missiles?

      Other notes on F-15K: Larger parts and avionics imported for final assembly by Boeing in STL. Does this count as Korean-made?

      • STemplar

        The US only stores nukes physically in Europe outside the US now, or so they say…

        The SKoreans have a cruise missile variant but their ballistic missiles are limited to 300km range and 50kg payload.

        • STemplar


        • blight

          They also keep them in aircraft carriers, but adopt Israeli-style nuclear ambiguity about it.

          I’m sure they don’t keep them in Japan, especially since some things are hard to keep secret, and keeping something like /that/ secret would totally blow away Japan’s and the United State’s working military relationship.

  • Does not look as good as the Japanese Stealth Projects Model that came out last year. The Mitsubishi model looked very well finished. Dont know if they have continued on it. Still love the New Kawasaki P-2 and KC-2, awesome.

  • F35 Insane

    We need to put DoD in charge and stop this progress immediately!

  • Stratege

    What is “Russian copy cat method”. PAK-FA is not near where copy of anything,
    S.Korean KF-X on paper does not look like a clone of F-22 too.

  • P.Herrmann

    I have been involved for many years in the FX and KFX campaigns in Korea.Over the almost 15 years of continous support of military campaigns in ROK I have learned that we as European OEMs never ever will srand a chance of selling a nut or a bolt for a strategical Project in this country.The almighty arm of uncle Sam is so strong ,that the Koreans never will decide for anything else other than US.