TR Air-Force TF-X KAAN Fighter Jet

[Dosirak]

I defer to your better knowledge. However, from the mouth of the head of TAI in mid- December I heard that TAI were still aiming for the 27th December as FF date. In January I heard FF would be in days IIRC. No mention that CFR had been completed. No mention of waiting for completion of CDR before FF 27th December. No mention in January of waiting for completion of CDR before FF in a few days.

Earlier this month Mr Kotil said Kaan FF would be in the coming days. You said it will be in years. Perhaps you can understand why I bemused.

PS Kaan is not important to me in terms of my national security. The RAF is not anticipating putting Kaan into service. I do, however, have an interest in aviation, so I am interested in following progress in the project, including when Kaan's FF is likely to be.

Well, the head of TAI either misled the people or simply lied.

However, when the Air Forces Command of Turkey presented a timeline of TF-X development in 2021, it was clearly stated that CDR would be completed in late 2024 and 'First Flight' would be conducted in late 2026.

 

[Windchime]

Well, the head of TAI either misled the people or simply lied.

However, when the Air Forces Command of Turkey presented a timeline of TF-X development in 2021, it was clearly stated that CDR would be completed in late 2024 and 'First Flight' would be conducted in late 2026.

You are remembering correctly, and that plan is still more or less the same, albeit it has been brought forward a bit. They are planning to carry out CDR later this year and roll out their first EMD prototype with actual mission critical avionics in the later years.

What we see today, the GTU-0, is more or less a developmental technology demonstrator. It doesn't have any of the mission critical avionics and had not even the flight computer until very recently.

Think about it this way. Turkiye until now has never developed a manned, supersonic aircraft, let alone a stealth fighter which also has aforementioned attributes. It actually needs some experience in terms of flight control design, as well as low observable planfrom design and evaluation capabilities. Had they took a more "sensible" route, they might have first developed Hurjet, gain experience in these matters and then proceed with a development of state-of-the-art 5th gen fighter, but that's unfortunately not an option for Turkiye.

Safe to say, the project management as well as outline of MMU program is pretty rough, considering all the changes to the program schedules mid-course, as well as its inherent risks, but conversely, I also personally think that it is actually pretty wise to use GTU-0 as a TD (although Turks call it a "prototype", which is not wrong in a literal sense, but considering how the term is commonly used, this thing is not a conventional "prototype" as you've said. Which is also the reason I'd say that you ain't wrong in saying that Temel Kotil is misleading people in a way.).

I'd describe GTU-0 and the next "prototype" under construction atm to be more similar to YF-22, ACX and EAP. The actual EMD prototype will only follow after CDR.

 

[Spitfire9]

Thanks for the info, all concerned. If the aircraft being built are what would be best described as technical demonstrators, that paints a different picture of the project to the one that I was seeing.

 

[Windchime]

Since we've got a chance here, I would like to discuss a bit more about what the Turks would be able to do with GTU-0.

Other than it being a great learning experience for TAI engineers in terms of design and development of flight controls and dynamics, as I've mentioned in above post, the opportunity it provides in terms of what Turkiye can learn in LO design could be very critical.

For instance, I could already think of a very basic radar observability evaluation campaign where they could fly the GTU-0 while tracking it with various airborne assets like F-16 and E-737, as well as surface based radars of Siper system and I-class.

These kinds of campaigns would probably not get public, but could definitely happen. It would provide very useful real world data concerning how the actual MMU planform performs against real fighter FCR operating in X band, AEW&C radar operating in L band, and various surface based MFR. Conversely, it would showcase how the newest gen Turkish radars perform agains LO targets.

Furthermore, it could be used as a testbed for various stealth materials like Turkish RAM. They could, for instance, test the RAM coated canopy glass on the GTU-0, akin to how the US tested Have Glass canopy before applying it to operational units. This would free the actual EMD prototypes from more mission critical performance evaluations.

To be honest, when I first beard that TAI decided to fly GTU-0, I thought it was mostly a publicity stunt, since in my view it made no sense to take a ground static test vehicle and make it fly, all the while the CDR is incomplete. Though the more I think about it, the more I see the benefits and opportunities. It would certainly mean higher development cost, though now it seems more like a risk-management measure more than anything else, which is quite ironic.

They are basically taking more risk now (of losing the aircraft) to gain crucial knowledge and know-how. No wonder TAI and SSB have very different positions regarding GTU-0. TAI wants to risk it considering the possible gains, since it's kore or less merely a TD. Loss of GTU-0 wouldn't be that critixal compared to the loss of an actual EMD prototype. On the other hand, being bureaucrats, SSB wouldn't want any of the headaches of possible loss of aircraft. The risks of losing GTU-0 in flgiht tests seems very real and present.

Lastly, what I could say with absolute confidence is that the test pilots are taking the biggest risk here, flying a prototype that wasn't supposed to fly, a plane that hasn't gone through ground static tests, a plane controlled by one of the first Turkish flight control system of this scale, bar Hurjet. You guys probably have a great deal of respect for those TAI pilots, but I think they deserve it even more flying this thing.

 

[Sanchez]

Since we've got a chance here, I would like to discuss a bit more about what the Turks would be able to do with GTU-0.

Other than it being a great learning experience for TAI engineers in terms of design and development of flight controls and dynamics, as I've mentioned in above post, the opportunity it provides in terms of what Turkiye can learn in LO design could be very critical.

For instance, I could already think of a very basic radar observability evaluation campaign where they could fly the GTU-0 while tracking it with various airborne assets like F-16 and E-737, as well as surface based radars of Siper system and I-class.

These kinds of campaigns would probably not get public, but could definitely happen. It would provide very useful real world data concerning how the actual MMU planform performs against real fighter FCR operating in X band, AEW&C radar operating in L band, and various surface based MFR. Conversely, it would showcase how the newest gen Turkish radars perform agains LO targets.

Furthermore, it could be used as a testbed for various stealth materials like Turkish RAM. They could, for instance, test the RAM coated canopy glass on the GTU-0, akin to how the US tested Have Glass canopy before applying it to operational units. This would free the actual EMD prototypes from more mission critical performance evaluations.

To be honest, when I first beard that TAI decided to fly GTU-0, I thought it was mostly a publicity stunt, since in my view it made no sense to take a ground static test vehicle and make it fly, all the while the CDR is incomplete. Though the more I think about it, the more I see the benefits and opportunities. It would certainly mean higher development cost, though now it seems more like a risk-management measure more than anything else, which is quite ironic.

They are basically taking more risk now (of losing the aircraft) to gain crucial knowledge and know-how. No wonder TAI and SSB have very different positions regarding GTU-0. TAI wants to risk it considering the possible gains. On the other hand, being bureaucrats, SSB wouldn't want any of the headaches of possible loss of aircraft. The risks of losing GTU-0 in flgiht tests seems very real and present.

Lastly, what I could say with absolute confidence is that the test pilots are taking the biggest risk here, flying a prototype that wasn't supposed to fly, a plane that hasn't gone through ground static tests, a plane controlled by one of the first Turkish flight control system of this scale, bar Hurjet. You guys probably have a great deal of respect for those TAI pilots, but I think they deserve it even more flying this thing.

For this exact reason, delays with GTU-0 are more than normal, even more so than the actual prototypes, and giving it a set date of first flight was always wrong.

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Playing the devil's advocate, if we had few F-35s flying around nowadays, we probably wouldn't do this. As we could just use the F-35s in the same role.

 

[infrared]

How many more times we need to hear that delays are totally normal? I believe it's been already said 40 times, everyone must have believed it by now. (My apologies for the ambiguity to the non-Turkish readers).

 

[Spitfire9]

To be honest, when I first beard that TAI decided to fly GTU-0, I thought it was mostly a publicity stunt, since in my view it made no sense to take a ground static test vehicle and make it fly...

Frame #0 was supposed to be a static test frame??? It sounds like it got waylaid somewhere along the line by non-engineering considerations.

 

[Windchime]

Playing the devil's advocate, if we had few F-35s flying around nowadays, we probably wouldn't do this. As we could just use the F-35s in the same role.

Possibly. The learning experience regarding supersonic aircraft design and control could be gained with Hurjet, that's for sure.

It would've been better if Hurjet development started a few years earlier, which would've provided TAI engineers more time to learn flight controls. The demand was always there ever since the TX-FX days, and they could've begun as early as when TAI was participating in T-X with SNC.

There always was the need to replace aging T-38s in THK, so it's kinda hard to understand why Turkiye decided to wait until 2017. I know that Hurjet is an internally funded project by TAI, but it's still counterintuitive nonetheless.

Though, I should note that usong F-35 wouldn't have provided as much design experience and LO know-how. It would've provided critical insights into the nature of the most advanced, network-centric stealth fighter, but conversely, it wouldn't have provided TAI any design experiences. There are some obvious pros and cons. You should lose one wide to gain another.

 

[Windchime]

Frame #0 was supposed to be a static test frame??? It sounds like it got waylaid somewhere along the line by non-engineering considerations.

Yes, that was what it was supposed to be (although GTU doesn't stand for "Ground Test Unit"), hence no flight control computers initially. They are taking risks that wouldn't have been taken by other more established players in the field of aerospace.

In the most extreme cases, the wings of this thing could snap under big loads and they wouldn't know that it will until it actually happens mid-air. I think the flight regime of GTU-0 would be pretty limited considering the unknowns.

 

[TheInsider]

Yes, that was what it was supposed to be (although GTU doesn't stand for "Ground Test Unit"), hence no flight control computers initially. They are taking risks that wouldn't have been taken by other more established players in the field of aerospace.

In the most extreme cases, the wings of this thing could snap under big loads and they wouldn't know that it will until it actually happens mid-air. I think the flight regime of GTU-0 would be pretty limited considering the unknowns.

That prototype has undergone full-size loading tests. Its wings won't snap under big loads.

Lastly, what I could say with absolute confidence is that the test pilots are taking the biggest risk here, flying a prototype that wasn't supposed to fly, a plane that hasn't gone through ground static tests, a plane controlled by one of the first Turkish flight control system of this scale, bar Hurjet. You guys probably have a great deal of respect for those TAI pilots, but I think they deserve it even more flying this thing.

This is wrong. Kaan prototype completed ejection seat tests, full-sized loading/static tests, inertia and static tests of control surfaces, landing gear fall tests, avionic tests in the system integration lab, fuel system tests, and engine tests.

 

[Windchime]

That prototype has undergone full-size loading tests. Its wings won't snap under big loads.

This is wrong. Kaan prototype completed ejection seat tests, full-sized loading/static tests, inertia and static tests of control surfaces, landing gear fall tests, avionic tests in the system integration lab, fuel system tests, and engine tests.

Thanks for the update. I've missed the report by Defence Turk from late last year and only just noticed since you've corrected me.

That's better, but flying GTU-0 is still a much riskier business compared to what other aircrafts have went through during their development. Using the same aircraft which was used for static ground testing and taking it to air is not a common practice. Also, flgiht control system tested via iron bird is obviously not subject to real operating conditions, and more importantly, it doesn't change the fact that it's one of the first Turkish manned, supersonic jet flight control system alongside that of Hujet.

Great deal of respect to the test pilots.

 

[Merzifonlu]

I guess I missed something. Are you sure the GTU-0 will fly?

 

[Spitfire9]

I guess I missed something. Are you sure the GTU-0 will fly?

I recall that when the wing load test was applied to A380 (150% of maximum load it was ever expected to encounter in service), the wing failed at 147%. Had it reached 150% but not failed, would it have been considered serviceable thereafter? What was GTU-0 subjected to in tests before being repurposed from static test to flying frame?

Having used it to enable a roll out ceremony to take place (objective achieved), wouldn't it better to repurpose it back to being a ground test frame?

 

[Saithan]

Thanks for the update. I've missed the report by Defence Turk from late last year and only just noticed since you've corrected me.

That's better, but flying GTU-0 is still a much riskier business compared to what other aircrafts have went through during their development. Using the same aircraft which was used for static ground testing and taking it to air is not a common practice. Also, flgiht control system tested via iron bird is obviously not subject to real operating conditions, and more importantly, it doesn't change the fact that it's one of the first Turkish manned, supersonic jet flight control system alongside that of Hujet.

Great deal of respect to the test pilots.

You mentioned earlier that Hürjet should have started earlier. I was thinking wouldn't we gain valuable knowledge and knowhow from starting production of Hürjet (light armed configuration/trainer jet). That could be useful for KAAN.

My point is that Hürjet has already flown, so we'd progres faster on that plane than KAAN. We'd uncover and test it's capabilities and truly progres in armed jet production.

I know some people mentioned Azerbaijan as potentiel customer, but that won't happen unless we have our own engine.

however the issue we have atm is that we need to update our own airforce and we need to gain intimate combat knowledge with Hürjet. Ascertaining it's limitations and capabilities and how far we can push it are also important.

 

[Windchime]

I guess I missed something. Are you sure the GTU-0 will fly?

That's a weird questiom, imo. GTU-0 was all that TUSAS had in hand when they were initially planning for the 26th of Dec. FF. If not with the GTU-0, what would've been flown, have you thought?

 

[Windchime]

You mentioned earlier that Hürjet should have started earlier. I was thinking wouldn't we gain valuable knowledge and knowhow from starting production of Hürjet (light armed configuration/trainer jet). That could be useful for KAAN.

My point is that Hürjet has already flown, so we'd progres faster on that plane than KAAN. We'd uncover and test it's capabilities and truly progres in armed jet production.

I know some people mentioned Azerbaijan as potentiel customer, but that won't happen unless we have our own engine.

however the issue we have atm is that we need to update our own airforce and we need to gain intimate combat knowledge with Hürjet. Ascertaining it's limitations and capabilities and how far we can push it are also important.

The problem is that development of MMU flight control system is running concurrently with Hurjet flight control system development and flight testing. Most optimally, they would've had time to complete Hurjet and use experience gained from it to develop MMU.

I'm not saying that they aren't doing exactly that right now, but right now, since the two programs are runnung concurrently, it's closer to a live feedback-loop between the two programs. It probably works, but there's, again, higher risk involved. For most of these kind of big engineering projects, there are almost always a project review after its conclusion.

On top of that, what you're saying is very much correct, but those things are even more true in case Hurjet development commenced earlier. That's why I think an earlier development of Hurjet would've been much better, mostly because of risk management reasons. It would've also had more opportunities to capture the export market.

 

[Saithan]

The problem is that development of MMU flight control system is running concurrently with Hurjet flight control system development and flight testing. Most optimally, they would've had time to complete Hurjet and use experience gained from it to develop MMU.

I'm not saying that they aren't doing exactly that right now, but right now, since the two programs are runnung concurrently, it's closer to a live feedback-loop between the two programs. It probably works, but there's, again, higher risk involved. For most of these kind of big engineering projects, there are almost always a project review after its conclusion.

On top of that, what you're saying is very much correct, but those things are even more true in case Hurjet development commenced earlier. That's why I think an earlier development of Hurjet would've been much better, mostly because of risk management reasons. It would've also had more opportunities to capture the export market.

As it was mentioned earlier Hürjet is a project by TAI (private venture), and if Hürjet is to progres further and faster it's necessary to have some orders in the book already.

As you pointed out currently the experience from the Hürjet that is flying is likely being used for KAAN. But imo that will end at a certain point maybe even within a year.

I compare it with the race between the rabbit and turtle, but reality will catch up.

 

[Dosirak]

That's a weird questiom, imo. GTU-0 was all that TUSAS had in hand when they were initially planning for the 26th of Dec. FF. If not with the GTU-0, what would've been flown, have you thought?

As I said, Mr. Kotil either misled the people or simply lied. The head of TAI seems to have a habit of doing this. He initially claimed Hurjet will fly in Dec, 2022 and it didn't fly in that month. Then he claimed March 18, 2023 will the date when Hurjet would take off from the ground, but It didn't happen either. It was only April, 2023 that Hurjet made her first maiden flight. This kind of delay is completely normal, but it does make Mr. Kotil an unreliable source of information in regard to FF.

Therefore, I take Mr Kotil's claim about FF of any manned project of TAI with a healthy dose of scepticism.

However, it really doesn't matter GTU-0 flies today, tomorrow or anytime this year. An actual prototype will be built in accordance with the initial product baseline once CDR activities are carried out and Turkish Air Force only expects an actual prototype of TF-X KAAN to perform her maiden flight by late 2026.

I have always had my doubt about TAI's manned aircraft project schedules, but the development timeline looks quite reasonable if you could forget about GTU-0 and the fact that Turkey is trying to develop & integrate own turbofan engine to the platform within the same timeframe.

 

[Kartal1]

Therefore, I take Mr Kotil's claim about FF of any manned project of TAI with a healthy dose of scepticism.

Not only manned... We have another example with Anka 3 that was supposed to fly in Mart-May 2023. I don't mind if the first flight have to be postponed, but Kotil's statements are really misleading. My take on his statements is that he is doing it mainly for internal consumption and he knows very well what is the situation on the projects and their state of development/maturity. I prefer to hear that KAAN will not fly this year instead of listening to lies.

 

[Spitfire9]

Not only manned... We have another example with Anka 3 that was supposed to fly in Mart-May 2023. I don't mind if the first flight have to be postponed, but Kotil's statements are really misleading. My take on his statements is that he is doing it mainly for internal consumption and he knows very well what is the situation on the projects and their state of development/maturity. I prefer to hear that KAAN will not fly this year instead of listening to lies.

Is he being pressurised to announce good news prematurely?