HAL's supersonic HLFT-42 trainer jet facing delays due to lack of clarity from IAF

Hindustan Aeronautics Limited (HAL) is hitting some turbulence with its ambitious project, the HLFT-42 supersonic trainer jet. The "Next Gen Supersonic Trainer" was unveiled in 2023 with the promise of revolutionizing pilot training for India's advanced fighter jets, even boasting capabilities as a light combat jet. But the dream is hitting a reality check as delays mount due to a lack of clarity from the Indian Air Force (IAF) and concerns over the project's financial viability.

The HLFT-42 was designed to be a multi-purpose powerhouse, with a 16.5-ton Maximum Take-Off Weight (MTOW) and a hefty 4.5-ton weapon payload. It was meant to prepare pilots for 4th and 5th generation fighter jets while also being capable of combat missions. But all this potential is stuck in limbo as HAL and the IAF haven't been able to finalize the aircraft's configuration or even decide on the engine.

This lack of direction is raising financial red flags. Without knowing how many units the IAF will actually buy, HAL is facing uncertainty about whether the project will be worth the investment. This is leading to delays and questions about whether HAL can even afford to keep the project going.

HAL is still determined to get the HLFT-42 off the ground, using their own funds and parts from existing Tejas programs to build a prototype. However, the lack of a final engine decision continues to be a major roadblock. HAL is aiming for a more powerful engine than the F-414 used in the Tejas MkII, but the specifics remain a mystery.

The delays caused by the IAF's indecision and the financial concerns are causing some to question whether HAL is even prioritizing the project. Even if these issues are resolved soon, the most optimistic prediction for a rollout is in the early 2030s.

The future of the HLFT-42 is hanging in the balance. Until the IAF provides clearer direction and the financial concerns are addressed, India's dream of a next-generation supersonic trainer jet remains grounded.

 

[beencensured]

HAL should focus extra profits on MTA and heavy lift aircraft, for these types of trainers there needs to define need as they are bigger than our fighter aircraft. We have LCA trainer, and they wanted an all-metal body trainer as cheaper, So, duplicating work of LCA TEjas trainer. .Focus on IMRH, and MTA which urgently needed. Otherwise, drones.

 

[Anant]

Here is an idea: Cancel the failed HJT-36 program, and divert funding and resources to the HLFT-42. For now, we can move ahead with a GE F404 engine, but if the Kaveri somehow works out, the HLFT-42 would be a better candidate to have the F404 replaced with the Kaveri than the Tejas would be.

Since the HJT-16 Kirans are at the end of their lives, simply convert a few BAe Hawks to advanced trainers to replace them, and look into a modernisation program for some of the newer HJT-16s to keep them in service for another 5-8 years.

Eventually, once the HLFT-42 gets going (and that should not be too difficult given it shares a lot of components with the Tejas), it can replace the Hawks and HJT-16s. As for order quantities, the HLFT-42 would become the primary advanced trainer for the IAF alongside the HTT-40 basic trainer, hence we can easily be looking at over 180 aircraft. Add in the Navy's Hawk and Kiran trainers, and you have an order book that will easily cross 225, that is, the HLFT-42 will quite possibly have a larger order book than the Tejas Mk 1/1A.

 

[Ashutosh]

Here is an idea: Cancel the failed HJT-36 program, and divert funding and resources to the HLFT-42. For now, we can move ahead with a GE F404 engine, but if the Kaveri somehow works out, the HLFT-42 would be a better candidate to have the F404 replaced with the Kaveri than the Tejas would be.

Since the HJT-16 Kirans are at the end of their lives, simply convert a few BAe Hawks to advanced trainers to replace them, and look into a modernisation program for some of the newer HJT-16s to keep them in service for another 5-8 years.

Eventually, once the HLFT-42 gets going (and that should not be too difficult given it shares a lot of components with the Tejas), it can replace the Hawks and HJT-16s. As for order quantities, the HLFT-42 would become the primary advanced trainer for the IAF alongside the HTT-40 basic trainer, hence we can easily be looking at over 180 aircraft. Add in the Navy's Hawk and Kiran trainers, and you have an order book that will easily cross 225, that is, the HLFT-42 will quite possibly have a larger order book than the Tejas Mk 1/1A.

Everything u said is good but I would recommend to rather go with locally produced F414 instead of buying a F404. F414 is better while having the same dimensions.

 

[Arunangshu Chakraborty]

Why can't they use the Dry Kaveri engine for a trainer aircraft?

 

[Boomeranger]

Make MK2 HLFT42 with twin GEF404 engines and replace all Jaguars with same jet! Can build 400 nos. of these low level tree top height flight - ground attack jets next!

 

[Boomeranger]

Why can't they use the Dry Kaveri engine for a trainer aircraft?

only 45KN max. thrust engines means, cannot train pilots for dog fighting then...

 

[Anant]

Make MK2 HLFT42 with twin GEF404 engines and replace all Jaguars with same jet! Can build 400 nos. of these low level tree top height flight - ground attack jets next!

Calm down, please. Don't rush. Take a deep breath.

To start with, your suggestion is nonsensical from the perspective of your idea of using two engines. You can't just modify an existing single-engined aircraft design to add a second engine or vice versa. A twin engined HLFT-42 wouldn't be the HLFT-42 at all. It would be some other aircraft developed from the HLFT-42. We do not have the requirement for that sort of thing.

Coming to the second part, the HLFT-42 will remain a LIFT/LCA jet for now. Converting it to a ground attack aircraft is certainly possible, and is something that should be looked into, considering the HLFT-42 draws from the venerable HF-24 Marut, which was regarded as a good ground attack aircraft.

 

[Anant]

Why can't they use the Dry Kaveri engine for a trainer aircraft?

The Dry Kaveri would not have sufficient thrust for an aircraft of that size in a single-engined configuration. You'd struggle to pull off certain maneuvers, let alone use it as an advanced trainer.

 

[Boomeranger]

Calm down, please. Don't rush. Take a deep breath.

To start with, your suggestion is nonsensical from the perspective of your idea of using two engines. You can't just modify an existing single-engined aircraft design to add a second engine or vice versa. A twin engined HLFT-42 wouldn't be the HLFT-42 at all. It would be some other aircraft developed from the HLFT-42. We do not have the requirement for that sort of thing.

Coming to the second part, the HLFT-42 will remain a LIFT/LCA jet for now. Converting it to a ground attack aircraft is certainly possible, and is something that should be looked into, considering the HLFT-42 draws from the venerable HF-24 Marut, which was regarded as a good ground attack aircraft.

There was MK1 version of HF24 with twin engines of Gnat jet's Adour Rolls Royce actually! Then they tested MK2 single MIG21 engines version which crashed on take off and killed expert Test Pilot Wing Commander Das of HAL in 1970's..

 

[Boomeranger]

BEST replacements for Jaguar jets would be twin GE-F404 engines powered HLFT42 actually; for terrain hugging very low level ground attacks...

 

[Akshat]

Why can't they use the Dry Kaveri engine for a trainer aircraft?

Trainers means it will be used by less experienced pilots. Kaveri is highly unreliable. Last time it was flown on an aircraft it ended up throwing ninja blades and blasting off in air. Single engine planes, especially trainers, need highly reliable engines.

 

[Anant]

There was MK1 version of HF24 with twin engines of Gnat jet's Adour Rolls Royce actually! Then they tested MK2 single MIG21 engines version which crashed on take off and killed expert Test Pilot Wing Commander Das of HAL in 1970's..

Nope, the Marut was never fitted with the R-13 or R-25 engines found on the MiG-21. The proposed Marut Mk 2 would have been powered by two RR Turbomeca Adour engines instead of the Orpheus engines.

Oh, and Cdr. Das's crash was on a prototype Marut that was refitted with reheated Orpheus engines as an experiment of increasing the thrust output. The engines were a modified Orpheus engine, not any other model.

 

[Anant]

BEST replacements for Jaguar jets would be twin GE-F404 engines powered HLFT42 actually; for terrain hugging very low level ground attacks...

You can't just take a single-engined aircraft and add a second engine. That essentially amounts to redesigning the whole aircraft. A F404 or F414-powered Marut can be a good ground attack aircraft if modified for that role, but it will remain a single-engined aircraft.

 

[Sandeep]

It would be best that HAL keeps working with the Air Force to make sure the 3rd stage trainer meets their expectations and requirements. It will have to be a modern trainer that not only teaches them how to fly but also how to use its technology, weapons and capabilities to prepare them in any eventual war. Hopefully within the next 10 years they can develop a trainer and it is ready for production but the Air Force and HAL already have a large number of purchases it needs to make ranging from the Tejas MK1A, MK2, AMCA, LCH, LUH, IMRH, basic trainer, intermediate trainer and also a range of SAM systems, radar systems, armed drones, swarm drones, surveillance drones, cargo drones. This would keep HAL busy for the next 50 years but it can be shorter if they can expand their manufacturing capabilities or sub contract it to the private sector. We need more participation from the private sector in making not just parts and components but the entire jet or drone to meet the high demand of orders our Air Force needs.

 

[The Presence]

Trainers means it will be used by less experienced pilots. Kaveri is highly unreliable. Last time it was flown on an aircraft it ended up throwing ninja blades and blasting off in air. Single engine planes, especially trainers, need highly reliable engines.

Kaveri didn't throw blades in aerial tests, neither did it blow up in the air.
If it continued throwing blades like it did on the ground, it would've never been allowed to be mounted on an aerial platform.
It just couldn't deliver enough thrust for it's weight, that's all.

 

[Akshat]

Kaveri didn't throw blades in aerial tests, neither did it blow up in the air.
If it continued throwing blades like it did on the ground, it would've never been allowed to be mounted on an aerial platform.
It just couldn't deliver enough thrust for it's weight, that's all.

That’s why one shouldn’t comment on things beyond their understanding.

A Kaveri engine flying on an Il76 ended up catching fire in 2011 in Russia. I have posted multiple links of that here in the past. You can go and google it if you want to.

 

[Boomeranger]

You can't just take a single-engined aircraft and add a second engine. That essentially amounts to redesigning the whole aircraft. A F404 or F414-powered Marut can be a good ground attack aircraft if modified for that role, but it will remain a single-engined aircraft.

I meant re-design only!! Just like Tejas MK2 can be made into an ORCA BUT, IAF is NOT interested for that and, Not even on TEDBF also so far..

 

[Boomeranger]

Nope, the Marut was never fitted with the R-13 or R-25 engines found on the MiG-21. The proposed Marut Mk 2 would have been powered by two RR Turbomeca Adour engines instead of the Orpheus engines.

Oh, and Cdr. Das's crash was on a prototype Marut that was refitted with reheated Orpheus engines as an experiment of increasing the thrust output. The engines were a modified Orpheus engine, not any other model.

read here

https://indiandefence.quora.com/HF-73-The-Lost-Opportunity

Suranjan Das - Wikipedia

en.wikipedia.org

 

[Boomeranger]

That’s why one shouldn’t comment on things beyond their understanding.

A Kaveri engine flying on an Il76 ended up catching fire in 2011 in Russia. I have posted multiple links of that here in the past. You can go and google it if you want to.

First dry ground test on bench engine exploded at GTRE...

 

[Anant]

read here

https://indiandefence.quora.com/HF-73-The-Lost-Opportunity

Suranjan Das - Wikipedia

en.wikipedia.org

And nowhere in your sources is it mentioned that the Marut Cdr. Das was flying was carrying some new engine. No, a simple search and cross-referencing online will tell you he was flying a Marut with a modified Orpheus engine set, which included a mechanism for reheating to increase engine thrust, since the Marut was considered underpowered for its time.

 

[The Presence]

That’s why one shouldn’t comment on things beyond their understanding.

A Kaveri engine flying on an Il76 ended up catching fire in 2011 in Russia. I have posted multiple links of that here in the past. You can go and google it if you want to.

Didn't find anything. Give me your links.

 

[Sentoki]

The HLFT-42 is already turning out to be a disappointment and a paper tiger even before it rolls out. Even from the unveiling HAL has not demonstrated clarity on what the objectives are for the HLFT-42.

1. Is it a trainer or an air superiority figther? If it is a trainer, why was the display model and rollout advertising BVR missiles on all hard points?
2. If it is a trainer, why is HAL so worried about MTOW and it being higher than MK1a?
3. For a trainer, why do you need an engine more powerful that GE-F414? For reference, the Boeing/Saab T7 will have an F404 engine with a peak thrust of 77KN, which is right in line with the Kaveri AB version. The Hongdu L15 uses two 28KN AL222 engines and comfortably reaches Mach 1.3. So i dont understand the obsession for a more powerful engine than our current frontline fighter (Mk1A). The only logical reason could be that, because this is a conventional all metal plane compared to the Tejas, the dry weight is higher and so they need a more powerful engine to have a higher MTOW than Mk1A. Which brings me back to the first question again; is it a trainer or a air superiority fighther/interceptor?
4. HLFT42 can be a great proving grounds for the Kaveri engine. I know many will say, you don't put an unproven engine in a new plane. You can use F404 engines for technology demonstrators & prototypes to continue development of all other LRU's and then swap with Kaveri when it is time to go into production. This will also give GTRE the time to test the Kaveri engine for its reliability on other twin engine fighters like the Mig-29.
5. If HAL absolutely wants a high powered engine, why not the RD33 MK engine? It is rated for 88KN peak thrust with similar dry weight to the the F414 engine. Thrust level is between the 404 & 414. Service life has been increased to 4000 hours. HAL already has got the license and capability to produce these engines in the Koraput facility. They just signed an agreement to make these engines for the MIG-29s. Overall seems like a no brainer and a readily available solution.
6. At the unveil, HAL seemed to suggest that, they are going forward with this project with or without IAF because IAF never actually mentioned a need for a trainer. HAL made comments that since LRU's are borrowed from Mk1A, the development time and cost will be lower. Now, they can't seem to get this project off the ground without IAF commitment, which is contrary to their initial statements.

 

[RG]

HAL must develop this platform as a cheaper option, it should be flexible enough to adapt any engine from F414 to AL-31FP, that will be produced in India. Low cost and number is a quality too.