Kaveri & Aero-Engine: News & Discussion

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chola
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Re: Kaveri & aero-engine discussion

Post by chola »

Pratyush wrote:I have asked this question multiple times . Will ask once again.

It was known ny 2009 /10 that Kaveri will not work out for the Tejas. When it was delinked from the program.

Why was a new effort not launched by GOI to build a replacement taking into consideration all the lessons learn from kaveri.

Also for the AMCA no efforts are being made for the design of a new engine.

That is easily answered. If the replacement engine is to be a turbofan then why not just continue with the Kaveri? A new turbofan taking all the lessons learned from the kaveri is just a continuation of the kaveri!

The problem is not mismanagement of the Kaveri program. The problem is the simple fact that we just do not have the manufacturing foundation for a turbofan yet. Setting up a new project team won’t suddenly create this ability.

Look at the RD-33 where Russia, with all its great experience, is still having problems after four decades of research, development and manufacturing. We were asking for an engine that is equivalent of western-state-of-the-art F404 and M-88. In the 1990s! When even today we do not have an indigenous turbojet, turboprop or even piston engine to fit into aircraft of any class.

Again, perhaps we should have built a mass produced turbojet like the Tumansky on the MiG-21 (not a just demonstration turbojet like the GTX-37.) But then again a turbojet would not have fulfilled the specs we set forth for the LCA so we would have needed to scale down our ambitions to a single-engine design more akin to a fully indigenous Bison perhaps.

The lack of the foundational steps hurts us everywhere and not just at the high end like the LCA and AMCA. If we had a turboprop or even a simple reliable piston engine, the UCAV/UAV development would have come along faster and with more designs instead of just the Rustom I/II.

BTW, I dont fault our ambition on the Kaveri/LCA but that exuberance should have been backed up with more practical designs that the Indian manufacturing and technical base could have supported at the time. Shooting for the moon is not a bad thing, just have a backup plan in case the moon is too far away for the rifle you own.
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Re: Kaveri & aero-engine discussion

Post by JayS »

Pratyush wrote:I have asked this question multiple times . Will ask once again.

It was known ny 2009 /10 that Kaveri will not work out for the Tejas. When it was delinked from the program.

Why was a new effort not launched by GOI to build a replacement taking into consideration all the lessons learn from kaveri.

Also for the AMCA no efforts are being made for the design of a new engine.
Unless its a rhetorical question, do you really expect someone will/can answer for that "Why". Or any answer given here will satisfy you..? A book can be written on this or one can simply shake head and ignore thinking "Its like this only in India".
Eric Leiderman
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Re: Kaveri & aero-engine discussion

Post by Eric Leiderman »

P&W are testing a turbo fan engine with a gear box that decelearates the compressor from the turbine, with an estimated 15% gain in efficiency
The reason for reducing the the compressor is the fan tips are have an angular velocity greater than the spped of sound , which causes issues with compressor efficiency.

Sorry for the long winded intro, however if gurus could answer questions.

In a fighter aircraft with a smaller dia for compressor would the efficiencies be comparable? Are any of the major turbo engine OEM's getting something ready for military applications?

a 15 % increase in range would be something to think about.
shiv
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Re: Kaveri & aero-engine discussion

Post by shiv »

Eric Leiderman wrote:
In a fighter aircraft with a smaller dia for compressor would the efficiencies be comparable? Are any of the major turbo engine OEM's getting something ready for military applications?

a 15 % increase in range would be something to think about.
By no means a guru - but I try to keep up with what is happening on the engines side of things.

Do not expect anything similar to happen for military engines for several reasons

1. The "efficiency" that they aim for in civil engines is for the engine to run at pretty much constant speed and the most efficient altitude. They are not looking for sudden changes in RPM and altitude that military engines require (except transports maybe). Sudden changes in RPM, surges or power etc could end up being a real headache for the reduction gearbox.

2. Civil engines are made efficient by the realization that a "core" (narrow) engine has the potential to develop far faar more power if the fans could be much broader and bypass air around the engine - this is the reason for the wide-mouthed "Aaaaaaaaaah" engines in civil air liners. But those broader fans with longer fan blades have traditionally been made to turn at a speed that is controlled by the core engine itself - using a common central shaft. The longer blades spinning faster were more likely to go supersonic at the tips as a result restricting the RPM of the core engine itself. If a real kick-ass gearbox could be made to reduce the speed of the broader "fan" section - efficiency can be improved allowing the core engine to run faster and hotter , but the engine faceitself also becomes very broad with long fan blades and not compact as is more desirable for a space-challenged combat aircraft where you cannot simply hang a broad faced "Aaaaaaaaah" saying engine off the wings like Boeing or Airbus. The Boeing 777 engines are particularly "Aaaaaaaah!" wide open - a man can stand at the engine entrance and hope the pilot does not press the "aage chalo" button or whatever

3. The long fan blades of high bypass engines have more inertia and take more time to spool up to higher RPM. This is fine for a civil airliner that does not need to accelerate suddenly - but useless for a military jet that may have to go for sudden acceleration and deceleration and airflow changes. For example the "tailslide" of the MiG 29 and other aircraft - the plane is made to zoom up vertically on full power + afterburner - and then the engine is cut off to a much lower power setting to it stops climbing, slows down and starts sliding backwards and down.

The A 320 crash in Bengaluru in the1980s (in which we lost some friends) resulted from the fact that the pilot (I think) found himself too low on the approach and tried to spool up the engines (increase power) - but those efficient high-bypass engines needed 15 seconds to reach full power. Contrast that with airshows where a fighter simply turns around, lines up and lands like the pilot needs to go to toilet urgently. Most fighter engines tend to have low bypass ratios that are less efficient that staid civil engines in terms of fuel burning, more compact in size and better capable of sudden acceleration and deceleration
shiv
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Re: Kaveri & aero-engine discussion

Post by shiv »

Pratyush wrote: Why was a new effort not launched by GOI to build a replacement taking into consideration all the lessons learn from kaveri.
Who in India would GoI have approached to make a new engine?

1.Ask GTRE that had already taken decades and failed?
2. Ask HAL which has never designed a de novo engine?
3. Ask Infosys/WIPRO/Kirloskar/L&T/Tata/Mahindra who have never built a jet engine ever?
4. Approach SNECMA, GE, Pratt and Whiney, Safran, Klimov, Tumansky, Rolls Royce etc who have built engines for 70 years.

What we have now is 2 and 4. HAL is building 2 engines and they have asked for phoren help in other cases
JayS
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Re: Kaveri & aero-engine discussion

Post by JayS »

Eric Leiderman wrote:P&W are testing a turbo fan engine with a gear box that decelearates the compressor from the turbine, with an estimated 15% gain in efficiency
The reason for reducing the the compressor is the fan tips are have an angular velocity greater than the spped of sound , which causes issues with compressor efficiency.

Sorry for the long winded intro, however if gurus could answer questions.

In a fighter aircraft with a smaller dia for compressor would the efficiencies be comparable? Are any of the major turbo engine OEM's getting something ready for military applications?

a 15 % increase in range would be something to think about.
I guess you are talking about PW1000G series. In that case the one engine is already in service. Two are in advanced flight testing and will be in service by 2020-21. One more will come eventually.

It has gear box to reduce speed of Fan not compressor. The Gearbox connects LP shaft to Fan. Reduction ratio is about 3:1. LP Compressor is different, and Fan is different module in Civil engines. In mil engines Fan is part of LPC or Booster.

Civil and military engines are designed with very different design goals and seat on a different part of Turbofan spectrum now. Its difficult to compare efficiency based on single parameter namely diameter.

There is no publically know program for use of GTF in Mil engines. Mil engies are moving towards Adaptive or Variable cycle operations. Efficiency and cost is not of paramount importance in Mil engines, performance and reliability are.
chetak
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Re: Kaveri & aero-engine discussion

Post by chetak »

shiv wrote:
The A 320 crash in Bengaluru in the1980s (in which we lost some friends) resulted from the fact that the pilot (I think) found himself too low on the approach and tried to spool up the engines (increase power) - but those efficient high-bypass engines needed 15 seconds to reach full power. Contrast that with airshows where a fighter simply turns around, lines up and lands like the pilot needs to go to toilet urgently. Most fighter engines tend to have low bypass ratios that are less efficient that staid civil engines in terms of fuel burning, more compact in size and better capable of sudden acceleration and deceleration
The pilots had a huge fight in the cockpit prior to take off from Bombay because due to a last minute and unannounced crew substitution, a " junior" was to ride check on his "senior".

This was when the airbus was a new entrant to the airline and the envelope protected entity was an ill understood concept among flight crews.

After the fight, all communications ceased between the cockpit crew who were both command rated.

Approach to BLR was made in the wrong mode, a mistake that was not caught by both crew and they wound in an unrecoverable situation quite close to the ground. The pilot opened throttle and also pulled back on the "stick".

the V2500 engines, like all other big engines has a time lag before they spool up (about 6-8 seconds) and deliver the demanded power, unlike a turboprop where power delivery is almost instantaneous.

In the meanwhile, back at the ranch, the envelope protected software suppressed the nose up command because, at that height, it had determined that the tail would have struck the ground had it allowed the sharp nose up attitude that was required.

This fatal accident was decided in Bombay, even before takeoff and it was just looking for a place to happen.

Around this time, give or take, an airbus "test" pilot also mushed into the ground during an airshow demonstration because even he hadn't quite grasped the fundamentals of an "envelope" protected aircraft.

I have seen hundreds of routine analyses of many many airline flight data recorders and it is surprising as to how many command qualified pilots still don't seem to get or even understand envelope protection.
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Re: Kaveri & aero-engine discussion

Post by Rishi_Tri »

chetak wrote:
shiv wrote:
The A 320 crash in Bengaluru in the1980s (in which we lost some friends) resulted from the fact that the pilot (I think) found himself too low on the approach and tried to spool up the engines (increase power) - but those efficient high-bypass engines needed 15 seconds to reach full power. Contrast that with airshows where a fighter simply turns around, lines up and lands like the pilot needs to go to toilet urgently. Most fighter engines tend to have low bypass ratios that are less efficient that staid civil engines in terms of fuel burning, more compact in size and better capable of sudden acceleration and deceleration
The pilots had a huge fight in the cockpit prior to take off from Bombay because due to a last minute and unannounced crew substitution, a " junior" was to ride check on his "senior".

This was when the airbus was a new entrant to the airline and the envelope protected entity was an ill understood concept among flight crews.

After the fight, all communications ceased between the cockpit crew who were both command rated.

Approach to BLR was made in the wrong mode, a mistake that was not caught by both crew and they wound in an unrecoverable situation quite close to the ground. The pilot opened throttle and also pulled back on the "stick".

the V2500 engines, like all other big engines has a time lag before they spool up (about 6-8 seconds) and deliver the demanded power, unlike a turboprop where power delivery is almost instantaneous.

In the meanwhile, back at the ranch, the envelope protected software suppressed the nose up command because, at that height, it had determined that the tail would have struck the ground had it allowed the sharp nose up attitude that was required.

This fatal accident was decided in Bombay, even before takeoff and it was just looking for a place to happen.

Around this time, give or take, an airbus "test" pilot also mushed into the ground during an airshow demonstration because even he hadn't quite grasped the fundamentals of an "envelope" protected aircraft.

I have seen hundreds of routine analyses of many many airline flight data recorders and it is surprising as to how many command qualified pilots still don't seem to get or even understand envelope protection.
A Lil OT but still recall the images and remember reading detailed report on this. Of course, at least in airliners the communication between pilots perhaps plays the largest role as evidenced in so many unfortunate incidents that are well documented.

As to the more 'mechanical' cause (I am no A320 expert nor claim to be one), the report stated that the aircraft was in 'Open Descent Mode' which prevented the engines from being powered up. So, though the commander, powered up the engine didn't respond and rest of the sequence happened. The commander, despite communication breakdown in cockpit, would have known from his experience that he was not in best approach. The report further stated that had the aircraft been in 'full power on mode' it would not have happened. Think this incident served to bring about changes in instructions and when to engage / disengage different modes. Tks
chetak
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Re: Kaveri & aero-engine discussion

Post by chetak »

Rishi_Tri wrote:
chetak wrote:
The pilots had a huge fight in the cockpit prior to take off from Bombay because due to a last minute and unannounced crew substitution, a " junior" was to ride check on his "senior".

This was when the airbus was a new entrant to the airline and the envelope protected entity was an ill understood concept among flight crews.

After the fight, all communications ceased between the cockpit crew who were both command rated.

Approach to BLR was made in the wrong mode, a mistake that was not caught by both crew and they wound in an unrecoverable situation quite close to the ground. The pilot opened throttle and also pulled back on the "stick".

the V2500 engines, like all other big engines has a time lag before they spool up (about 6-8 seconds) and deliver the demanded power, unlike a turboprop where power delivery is almost instantaneous.

In the meanwhile, back at the ranch, the envelope protected software suppressed the nose up command because, at that height, it had determined that the tail would have struck the ground had it allowed the sharp nose up attitude that was required.

This fatal accident was decided in Bombay, even before takeoff and it was just looking for a place to happen.

Around this time, give or take, an airbus "test" pilot also mushed into the ground during an airshow demonstration because even he hadn't quite grasped the fundamentals of an "envelope" protected aircraft.

I have seen hundreds of routine analyses of many many airline flight data recorders and it is surprising as to how many command qualified pilots still don't seem to get or even understand envelope protection.
A Lil OT but still recall the images and remember reading detailed report on this. Of course, at least in airliners the communication between pilots perhaps plays the largest role as evidenced in so many unfortunate incidents that are well documented.

As to the more 'mechanical' cause (I am no A320 expert nor claim to be one), the report stated that the aircraft was in 'Open Descent Mode' which prevented the engines from being powered up. So, though the commander, powered up the engine didn't respond and rest of the sequence happened. The commander, despite communication breakdown in cockpit, would have known from his experience that he was not in best approach. The report further stated that had the aircraft been in 'full power on mode' it would not have happened. Think this incident served to bring about changes in instructions and when to engage / disengage different modes. Tks
This seniority/juniority nonsense, excessive deference towards authority, the absolute unwillingness to challenge authority, even when the captain/senior does wrong, is a very peculiar asian character flaw and social phenomena. It has led to many a fatal accident.

The last major and fatal CRM eff up in India was the AI express boeing crash in mangalore.

Remember the incident where an engineer was sucked into the aircraft engine at Bombay??
According to an eyewitness, it appeared that the flight captain may have started the engine before the clearance, though officials could not confirm this immediately.

Subramanian was near the nose wheel along with the pushcart when the engine started and he was sucked in.
this was also another CRM failure.

elsewhere this would probably come under Culpable homicide, not amounting to murder.

There is a process called "CRM, cockpit resource management" which is taught to all airline air crew which is supposed to take care of smooth and fail safe crew interaction, communication and cooperation in the cockpit.
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Re: Kaveri & aero-engine discussion

Post by Cybaru »

IAF doesn't seem to be happy with Russian engines from all indication. It doesn't think Russia is materially as well functionally.

Is there any way we could start working with Safran and RR on multiple engine projects that would end up powering the next generation of our fighters and helicopters?

For us GTRE isn't there yet. And perhaps they have a long way to go, but still it should be possible to do what we are doing for Tejas and start working for future projects from get go like AMCA, PAKFA, MKI Super-30, Mig29 and mig29K. This is one project we should throw as much money as possible. 60% control on our engine is far better than zero percent control.

Navy and Indian Railways would benefit hugely as well.
ramana
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Re: Kaveri & aero-engine discussion

Post by ramana »

The problem to me is the Research mentality of GTRE (Gas Turbine Research Establishment).

Asking them to design an engine is wrong task.
They can do research and their papers are among the best in the world but design requires a different mindset.
Its not there in the GTRE.
The same attitude hinders DRDO.

If you note DRDO greatest success was when Kalam was in charge.
He was a technologist and not a researcher.

You cant innovate what you don't make.


Maybe the GTRE should be confined to pure research and the design group split away and work with HAL Engine division to ensure things get innovated.

If needed it can have design engineers from HAL also in it.

Call it Gas Turbine Engine Design Group.

Not a Laboratory.

Current model is unsustainable and worse unproductive.
Vivek K
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Re: Kaveri & aero-engine discussion

Post by Vivek K »

You're right. HAL's Engine Division should collect its specialists and take the people closest to the Kaveri and spin this into an Hindustan Jet Engine (HJE) Manufacturing Company. And the research minded folks with GTRE should be sent to Midhani and given GOI support to build a company called Defense Metallurgy Ltd.

That would be much better than GTRE. But one of their tasks should be to duplicate the performance of a bison engine (Tumansky R-25?) before starting on the Kaveri.
ramana
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Re: Kaveri & aero-engine discussion

Post by ramana »

Vivek K we have convergence!!!

I know you are an engineer.
Can you write a policy paper on this focusing on the need, synergies, and benefits and why current mode is not working.
I would rather they work on Jaguar or Mig-29 engines as the Bisons will get phased out.
Modern engine with the same footprint and FADEC with longer life.
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Re: Kaveri & aero-engine discussion

Post by Pratyush »

I have seen multiple posts regarding the need to work on a previous generation engine. If we are going to work on copying a jet engine, why not copy the 404. Which will have future application for the IAF.
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Re: Kaveri & aero-engine discussion

Post by chola »

Pratyush wrote:I have seen multiple posts regarding the need to work on a previous generation engine. If we are going to work on copying a jet engine, why not copy the 404. Which will have future application for the IAF.
Because the F404 is a turbofan like the Kaveri and we cannot build the Kaveri. The same goes for the Adour and RD-33 from the Jag and MiG-29 respectively.

Unlike a simpler turbojet, a turbofan has the intricate fan section in front as well as the bypass tube surrounding the the core.

Those two sections mentioned makes it far more expensive and so requires a turbofan to last longer which in turn requires the development of advance materials — which even the Russians have issues with today in the RD-33 and AL-31.

Look at the Iranian example. They are able to RE the J-85 turbojet from the F-5 for their Saqaeh but they are not able to do the same for the early generation F-110 turbofan of the F-14. It is many magnitudes harder. But by building a turbojet that can power production fighters Iran is productionizing the core for any future turbofan. The heart or core of any turbofan is a turbojet.

So a production turbojet is a foundational step we should take and targeting a Tumansky-like engine is an very achievable goal at our current level of development, especially in manufacturing.

I would go further back on the technical rung to turboprop and even pistons where we are not dealing high temperatures though those have their own intracies. The fact we have not master productionizing even those technically less advance engines mean we are attempting a turbofan with no foundation, i.e. in American parlance a moonshot.

And don’t think the lack of turbojet, turboprop and piston haven’t play havoc with our development elsewhere. We cannot even build prototype drones without importing a Lycoming piston for Rustom I or a Saturn turboprop for Rustom II. It is stifling our ability to build any aircraft from cropdusters to UAVs. We are so in intent with the high level stuff like 4th gen fighters that we forgo the huge range of aircraft that doesn’t require a state of the art turbofan.

The reason why Cheen is able to develop endless models of drones (not to mention cropdusters and light utility planes) and sell them everywhere is their companies have a readily available supply of local pistons and turboprops. They don’t have to import a fvcking piston for a goddam drone prototype like we needed to do.

Do the needful and build our foundation, please.
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Re: Kaveri & aero-engine discussion

Post by Vivek K »

ramana wrote:Vivek K we have convergence!!!

I know you are an engineer.
Can you write a policy paper on this focusing on the need, synergies, and benefits and why current mode is not working.
I would rather they work on Jaguar or Mig-29 engines as the Bisons will get phased out.
Modern engine with the same footprint and FADEC with longer life.
Will give it a shot Ramana!
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Re: Kaveri & aero-engine discussion

Post by Vivek K »

Chola you are absolutely spot on. Working and failing at the Kaveri is not too bad. However, not producing an R-25 style afterburning Turbojet for a country the size of India is perhaps criminal and treasonous! Especially when IAF was having spares issue, to have not stepped in with a turbojet - I would pin a lot of blame on DRDO for the deaths of 100s of pilots.

In the same vein, IAF and DRDO should have worked in the 80s to develop a Mig-21++ (kind of an Iron Bird LCA without the composites but without the high landing speeds of the Mig). They should have also developed twin engined prototypes to study the aerodynamics. A Marut body could have been prepared with two R-13 (R-25 came in later I think) or something similar to be technology demonstrators.

That is why the ADA should be either given more responsibilities in the Aviation sector or merged with HAL. ADA could be charged with building up Taneja Aerospace as a rival to HAL with some production lines for LCA set up with Taneja. NAL should be made a part of Taneja. GOI should use funds from HAL to develop capabilities with Taneja and DRDO should fund Midhani's efforts in metallurgy and also provide talented staff to Midhani for free.

I would love to see HAL/DRDO work on the following:
a) LCA - 500 a/c production (MK1, MK1A, MK II)
b) AMCA - Twin Engined fighter + naval variant (use all the knowledgebase from NLCA) - prototype TD to be in skies in 3-5 years (wishful thinking)
c) Conceptual Design - Long range Bomber to take the fight to distant shores using dedicated aircraft - if India wants to project power away from its shores.
d) AJT and IJT (ongoing - take to completion)
e) AESA and other radars for fighters, AWACS (ongoing presently)
f) 12 more EMB AEWs (wishful thinking)
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Re: Kaveri & aero-engine discussion

Post by chola »

^^^ That is a great point wih the deadly issue of MiG-21 spares and the high landing speed of the 21 itself. Necessity alone should have made us look into building a turbojet and reworking a modernized MiG-21 equivalent. But probably a combination of contract obligations — Russia would never allow us to put another engine into the MiG-21s we were assembling — and simply wanting the latest and greatest (FBW, composite and turbofan) kept us from doing so. All things and attitude that need to be fixed.

When you talk about AEW, look at this:
Image

A carrier aircraft for the tip of a superpower’s proverbial spear. Powered by the humble turboprop. So could you imagine all the possibilities if we had a production turboprop powering a modest airframe like the Saras? Instead, our Saras prototypes depend on PWs that were subjected to embargo after Pokhran.
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Re: Kaveri & aero-engine discussion

Post by Vivek K »

True. Need a new company to first develop a turbojet and a line of turboprops - these could also go into the HTT 40.

But why does India care so much for contract obligations - no one else does! Pakistan let the Chinese look inside the F-16, the Chinese REed the Mig-21, the SU-27, the Su-30. Why do we observe regulations that no one else does?

If our CFD staff are sitting around twiddling their thumbs, they should be tasked with modeling the aircraft in IAF inventory and study their aerodynamics and look for improvements. It is time for India to not play stupid anymore.
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Re: Kaveri & aero-engine discussion

Post by NRao »

There was a vid, posted by Brar, on IIRC the f-35. The skunk works engineer mentions that they used to tweak an engine, run it until it failed, figured out why it failed, found a fix and repeated the process until they got an engine they wanted. I think this is a common thread for "engine"s. I doubt there is a way around it. One can do only so much via RE. Flip side, there is no alternative to a local effort.

Also, there is a need to have a team that looks into disruptive techs. Beyond the effort to either complete the Kaveri or dup a F414. The two teams need to constantly hook up to ensure a contemporary engine, one that will be able to stand on its own on some platforms.

And form a base for future engines.

15-20 years IMHO. At least.
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Re: Kaveri & aero-engine discussion

Post by Vivek K »

NRao wrote:.... One can do only so much via RE. Flip side, there is no alternative to a local effort.

Also, there is a need to have a team that looks into disruptive techs. Beyond the effort to either complete the Kaveri or dup a F414. The two teams need to constantly hook up to ensure a contemporary engine, one that will be able to stand on its own on some platforms.

And form a base for future engines.

15-20 years IMHO. At least.
If Metallurgy is not a barrier, then RE can help you overcome design challenges. Also, how does it help to say 15-20 years and after the Kaveri experience, does it still take 15 years? Is Kaveri struggling for metallurgy or due to design?
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Re: Kaveri & aero-engine discussion

Post by chola »

Vivek K wrote:True. Need a new company to first develop a turbojet and a line of turboprops - these could also go into the HTT 40.

But why does India care so much for contract obligations - no one else does! Pakistan let the Chinese look inside the F-16, the Chinese REed the Mig-21, the SU-27, the Su-30. Why do we observe regulations that no one else does?

If our CFD staff are sitting around twiddling their thumbs, they should be tasked with modeling the aircraft in IAF inventory and study their aerodynamics and look for improvements. It is time for India to not play stupid anymore.
Well, you know my take on RE. I don’t think you can RE truly modern stuff like the F-16/Su-27/30 or F-404 or AL-31.

If the chini could RE the F-16, they would do it and the PAF would have unlimited supply of their favorite F-Solah. But even the PRC can’t and they didn’t with the Su-27/30 either. Those are pure ToT. I’ve shown that in other threads.

The MiG-21/Tumansky 25 and F-5/J-85 are the last reverse engineerable technology combination IMO. The J-7E/PG and the Iranian Saqeah are the last examples of real indigenous clones. J-10 and J-11 are technology transfers from Israel and Russia respectively.

So being faithful to contracts is not necessarily wrong. It’s negotiations that prioritize (politically sensitive) local offsets and jobs over actual tech transfers that is wrong.

That said, why should we not use the HAL Su-30 MKI line and what we’ve learnt from operating that line to build our own variants? Why should HAL cry and moan that the last 30 MKIs will be up soon? Hell, why not use the production line and the ecosystem built around the MKI in a new project? We can call it a new name and say it is a new indigenous aircraft if the Russians piss and moan. I bet you they won’t if the first couple of hundred or so of this Hindi Flanker use Russian AL-31s.
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Re: Kaveri & aero-engine discussion

Post by chola »

Vivek K wrote:
NRao wrote:.... One can do only so much via RE. Flip side, there is no alternative to a local effort.

Also, there is a need to have a team that looks into disruptive techs. Beyond the effort to either complete the Kaveri or dup a F414. The two teams need to constantly hook up to ensure a contemporary engine, one that will be able to stand on its own on some platforms.

And form a base for future engines.

15-20 years IMHO. At least.
If Metallurgy is not a barrier, then RE can help you overcome design challenges. Also, how does it help to say 15-20 years and after the Kaveri experience, does it still take 15 years? Is Kaveri struggling for metallurgy or due to design?
You see the issues we have had with the MKI’s AL-31 and the MiG-29’s RD-33? You think the Russuans don’t have the design down pat after all these years? Brand new Russian engines can generate power just as well as their western counterparts. They just break down a lot more and a lot faster than western engines.

So that tells me it is material. We will not be able to beat the Russians with our first design so if THEY are having these problems . . .

My guess is it is material related. Design can be inferred by taking engines apart. We’ve done enough with the RD-33 (which in the Kaveri class) to know the design. But taking apart an engine gives you NOTHING about the alloys going into making the actual parts of that engine.
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Re: Kaveri & aero-engine discussion

Post by ramana »

Or all those long endurance drones.

Its the combustion through the hot stage.

Fact that Kaveri will have a French core tells you something.

Anyway whats the progress of the HAl jet engine project?
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Re: Kaveri & aero-engine discussion

Post by shiv »

The Kaveri AFAIK is a working engine. Please allow me a rude analogy. Hammering Kaveri is like complaining that a genetically engineered lab grown test tube penis is not working. It cannot work until it is attached to a human and tested to do its thing.

By now, in any engine manufacturing country it would have been mounted on a flying test bed at home and would have made hundreds of flights. It would then have been tested on a real fighter test bed. Running the engine for 10,000 hours in a test tube er shed is no use. The oldest jet engines and many newer ones were not reliable. But even if an engine can fly for 10 hours it is enough for a few tests. Fly 25 minute sorties and then take the engine apart to see how the parts are doing. We need to develop a mindset and an ecosystem for engines. We have not done that. But I am hoping that HALs engines will work. That is the next great hope.

We cannot remain stuck in Kaveri mode forever. We need to move on and create new engines of differing thrust specs for different application. One lab and one engine simply does not cut it.

BTW - why can't a well equipped engineering college produce a gas turbine engine?
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Re: Kaveri & aero-engine discussion

Post by ramana »

Shiv asked:
BTW - why can't a well equipped engineering college produce a gas turbine engine?
Same reason GTRE cant produce a GT engine.

The college has very good engineering but not technology.

Makin products needs in addition to engineering, technology. The nitty-gritty of what should be the tolerances on the part to ensure free running at high temperatures, what pressure for the fuel pumps to inject fuel into the high pressure section of the turbine to ensure continuous combustion. In college we were taught how to calculate the overall compression ratio and the what blade frequencies (the beauty of Dan Hertzog's variable thickness disc natural frequency calculations etc.) etc. but not the technical drawings to make the parts. The first cut of design based on these calcs is all that is taught. Then it has to be built and the dimensions adjusted for the engine design to run smoothly. This part is left for the industry which is non-existent.


One guy in Voltas interview demanded how I will tolerance a shaft with stepped diameters. I left one part with out dimensions to allow for float. And he wanted to know why? I told him and he gave big lecture about how colleges don't teach such skills.
But obviously I did no? Turns out he was a from the ranks engineer and had a chip against college graduates.

Any way all they were making were assembly of water coolers and didn't need my skills.
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Re: Kaveri & aero-engine discussion

Post by Zynda »

ramana wrote: One guy in Voltas interview demanded how I will tolerance a shaft with stepped diameters. I left one part with out dimensions to allow for float.
Is this the float you are referring to is the floating bearing centre dimension? As illustrated in this figure below?

Image
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Re: Kaveri & aero-engine discussion

Post by ramana »

yeah some thing like that. Its was so long ago.

Not germane to this thread and sorry for bringing it up.
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Re: Kaveri & aero-engine discussion

Post by chola »

While doing research on Kaveri and how other nations managed on aircraft engines, I realized that we, Japan and Cheen are the ones who had even tested a prototype turbofan outside the Big Three of US, EU (UK/France) and Russia.

So comparison with the Japonese and chinis (again) would be most relevant. Cheen more relevant to our situation than Japan since the Japanese are technically on par with the Big Three but are under an enforced pacifist regime by the Amreekis so their history is skewed.

The Japanese have produced high bypass turbofan engines for transport and civvy planes for decades but mostly not the low bypass types for fighters except a few for trainers. (Their F-2 was originally designed to have indigenous airframe and engine but US pressure turned it into a F-16 derivative and a F-110 engine.) That could change in the future as Abe is a nationalist and their stealth X-2 has the XF-5 3D thrust vectoring turbofan.

So not only are the Japanese on a vectoring turbofan(!), they were so experienced and confident that two of them powered the X-2’s first flight in April, 2016. Albeit it is twin engine with a margin of safety, still can you imagine plugging a Kaveri on the LCA now never mind its first flight!

So comparison with Japan is probably not very useful.

Brazil, with Embraer is an aircraft manufacturing giant in the third world. Ahead of us and Cheen as a builder of civilian aircraft. But they have never attempted a turbofan and have only recently developed turbojets mainly for their drones and cruise missiles.

I’ll write up Cheen later (maybe in the Chin mil thread.) But the surprising thing about their turbofan program is that it originates in the CMF56 civvy turbofan for the DC 8.

The fact we got the Kaveri to a test platform in Russia was a MASSIVE achievement restricted to a very select few. But failure was probably a foregone conclusion when attempting something this difficult without a foundation. Sort of a heroic tragedy that was fated.
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Re: Kaveri & aero-engine discussion

Post by VKumar »

Vivek K wrote:True. Need a new company to first develop a turbojet and a line of turboprops - these could also go into the HTT 40.

But why does India care so much for contract obligations - no one else does! Pakistan let the Chinese look inside the F-16, the Chinese REed the Mig-21, the SU-27, the Su-30. Why do we observe regulations that no one else does?

If our CFD staff are sitting around twiddling their thumbs, they should be tasked with modeling the aircraft in IAF inventory and study their aerodynamics and look for improvements. It is time for India to not play stupid anymore.
Sir, powers that can influence armed forces to ignore or even vilify indigenous products can influence the defence manufacturing set up NOT TO COPY OR REPRODUCE FOREIGN MAAL.
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Re: Kaveri & aero-engine discussion

Post by dinesh_kimar »

^ Very good points from Chola Saar. His earlier post abt trying for a simpler R-25 class turbojet got me into " search" mode. Some points :

> Kaveri is very good effort by GTRE folk. Equivalent to an early mark of Snecma M-53 which was fielded in 1983-85 period. The later (current) engine mod came in abt 1987. If LCA is lighter than a M-2000, then pls field the Kaveri in a flying testbed.

> A Japanese paper was (is ?) downloaded by me, in english. The F3 engine development program and milestones were described. Apparently, there's a reliability test where the engine has to undergo an endurance cycle for 150 hours. If it passes this, it can be fielded in the aircraft. This is a benchmark for all western engines.

> The early F3 attempted by Japan was also a turbofan, but with a modest output of 12 KN, when introduced in 1981 (similar to our old HJE 2000 engine in HAL museum ?) . They prudently specified 2 x F3 engines for their AJT trainer. Later marks had 16 KN. Even Later , they put in FADEC (2003 timeline).

> Early problems with resonance, blades shedding , etc. (sounds familiar? ) were tolerated and solved. The latest versions have good reliability, SCBs, FADEC, etc.

> An experimental version built by IHI has a thrust of 34 KN, almost 300 % of the original 12 KN spec.

> The experience of building indigenous has stood the Japanese in good stead. Engine wise, they are very good in stuff like assembly, machining driveshafts, etc. They build engine test cells upto GE-90 / RR Trent class turbofans.

> They have domestic capability of small and medium engines (Japanese market is closed from trainers upto C-130 class which uses the F7 engine. No news abt any firm selling these stuff to Japan for last 15 years, happy to be corrected.) Stuff like thrust reversers (GE) and APUs (Honeywell) were not tampered with, probably to reduce risks by fielding proven accessories in a new engine.

So, seems like decent specs achieved with a desi turbofan, but get it flying after 150 h endurance passes. Weight of 1250 kg is tolerable compared to 1560 kg of early M-53, and approx. 2000 kg of J-79.
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Re: Kaveri & aero-engine discussion

Post by NRao »

Chola,

Good synopsis.

On China, I would be interested in their infrastructure: wind tunnels, CFD capabilities, testing equipment - including air crafts, land based facilities, etc, etc, etc.

Thanks
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Re: Kaveri & aero-engine discussion

Post by Rishi_Tri »

dinesh_kimar wrote:^ Very good points from Chola Saar. His earlier post abt trying for a simpler R-25 class turbojet got me into " search" mode. Some points :

> Kaveri is very good effort by GTRE folk. Equivalent to an early mark of Snecma M-53 which was fielded in 1983-85 period. The later (current) engine mod came in abt 1987. If LCA is lighter than a M-2000, then pls field the Kaveri in a flying testbed.

> A Japanese paper was (is ?) downloaded by me, in english. The F3 engine development program and milestones were described. Apparently, there's a reliability test where the engine has to undergo an endurance cycle for 150 hours. If it passes this, it can be fielded in the aircraft. This is a benchmark for all western engines.

> The early F3 attempted by Japan was also a turbofan, but with a modest output of 12 KN, when introduced in 1981 (similar to our old HJE 2000 engine in HAL museum ?) . They prudently specified 2 x F3 engines for their AJT trainer. Later marks had 16 KN. Even Later , they put in FADEC (2003 timeline).

> Early problems with resonance, blades shedding , etc. (sounds familiar? ) were tolerated and solved. The latest versions have good reliability, SCBs, FADEC, etc.

> An experimental version built by IHI has a thrust of 34 KN, almost 300 % of the original 12 KN spec.

> The experience of building indigenous has stood the Japanese in good stead. Engine wise, they are very good in stuff like assembly, machining driveshafts, etc. They build engine test cells upto GE-90 / RR Trent class turbofans.

> They have domestic capability of small and medium engines (Japanese market is closed from trainers upto C-130 class which uses the F7 engine. No news abt any firm selling these stuff to Japan for last 15 years, happy to be corrected.) Stuff like thrust reversers (GE) and APUs (Honeywell) were not tampered with, probably to reduce risks by fielding proven accessories in a new engine.

So, seems like decent specs achieved with a desi turbofan, but get it flying after 150 h endurance passes. Weight of 1250 kg is tolerable compared to 1560 kg of early M-53, and approx. 2000 kg of J-79.
Kaveri may be seen as not meeting its objectives but it should be treated as a success. We have desi engine that works, produces wet / dry thrust of 80+/50+ KN, uses desi materials, has been tested under all conditions barring actually powering an aircraft.

Should be used to power any of the TD / PV LCA / Tejas gathering dust. Give it another 5 years, get whatever we can from Snecma, perhaps involve Kalyani for materials, and we may have a winner on hands.
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Re: Kaveri & aero-engine discussion

Post by chola »

NRao wrote:Chola,

Good synopsis.

On China, I would be interested in their infrastructure: wind tunnels, CFD capabilities, testing equipment - including air crafts, land based facilities, etc, etc, etc.

Thanks
Here goes.

To start off with, the current state of AC engines in Cheen is best described by the incorporation of the AECC (Aero Engine Corp of Cheen) in 2016. From wiki, the “corporation consists of 46 affiliate companies, including 22 engine companies, several institutes, and 3 aeroengine-repairing factories.”

Forty-six is obviously a massive number compared to our GTRE (research and design) and HAL (manufacture.)

I’ve identified a handful that are dealing with the well-known turbofans that their fanboys like to cream over:

Shenyang: WS-10, WS-20
Xian: WS-9, WS-15, SF-A
Guizhou: WS-13, WS-17
Chengdu: WS-18
Southern: WS-11

Not sure how the rest of the 22 engine companies breaks down but design, research and manufacturing of pistons and turboprops must occupy a good number of them. Historically turbojets were built by the elite companies now involved in the turbofan projects.

Windtunnels and dynamic fluids modelling capability can be inferred from their hypersonic test facility:

https://www.livefistdefence.com/2017/04 ... ility.html
This large facility of 660 acres located 6 km West of the Mianyang airport, Sichuan has three closed loop wind tunnels, two facilities for scramjet vacuum spheres and what appears to be a hypersonic impulse tunnel. The solid walled facility also has administrative buildings, auxiliary buildings and a large parking space. This facility is claimed to be largest wind tunnel testing facility in the world by some experts.
They have an IL-76 testbed identified in pictures carrying the WS-20 high by-pass.
Image
Also, we know they use J-11 testbeds for pairing the test engine (WS-10 variants) with a AL-31.

I’ll take four engines to describe the history of their industry. A key here is the origins of the first three came from the USSR but then parts and support were cut by the Sino-Soviet split while the fourth originated from the West which had components embargoed after the Tianenmen Square Massacre. In all cases, isolation forced the PRC to build the ecosystem from ground up with local parts.

Zhuzhou Huosai HS-6 radial piston: this powered the (iconic) CJ-6 trainers built in the thousands. Modern decendents power cropdusters, light utility and drones. Its origin is the AI-14R.

Zhuzhou WJ-6 turboprop: cloned from the AI-20 built for Y-8 An-12 Cub ripoff. Critically important as it powers a score of AWACS, ASW, Maritime Patrol, etc. variants of the Y-8X and Y-9. Also will power tha giant new seaplane AG-600.

Shenyang WP-7 turbojet: copied from the Russian R11-F-300 on early MiG-21s. This engine and its WP-13 descendent were built in the thousands for the J-7 — and allowed export of the MiG-21 ripoff. Experience from building turbojets, WP-6 (for J-6) and WP-7, led to Shenyang’s first turbofan, the WS-6. The WS-6 reached prototype stage with 8 built by the 1970s but by then Western engines had arrived in the form of the Rolls Royce Spey intended for the JH-7 and also the civilian engines that powered the McDonnell Douglas DC series being assembled in Shanghai.

Shenyang WS-10: this is Cheen’s main thrust into the modern turbofan. The key to its existence is the 1980s acquisition of two CFM-56s for the DC assembly before that collapsed post Tianenmen. The CFM-56, while a civilian high-bypass, is actually based on the F101 military turbofan that powered the B1 bomber and, in its derivative the F110, the F-14 and F-15. Shenyang would spend years trying to extract the F101 base out of the CMF-56 but then in the early 2000s got help from Russia. The WS-10 was actually being tested in Moscow at the same time as the Kaveri a decade ago. This seems to have allowed them to cover the last mile and the WS-10 is now installed hundreds of J-11B and J-16 Flanker ripoffs since 2010. The latest WS-10B variant was seem on a J-20 this year.

So an analysis of Cheen’s engine experience in relation to our GTRE/HAL/Kaveri comes down to the breadth and depth of their eco-system versus the fragile, thin layer that is ours. The Kaveri proved that ours is one of excellence since getting a modern turbofan to the testing stage puts us in a small select elite. But it is still a thin layer of excellence.

Turbofans are exceptionally hard. The WS-6 was their Kaveri. An interesting write up of it could be found here: https://www.globalsecurity.org/military ... na/ws6.htm. In the end, Cheen needed to import Western base technology and then sought Russian help to get their first productionized turbofan. But pursuing the WS-6 helped in building institutional knowledge and they now have multiple turbofan projects going concurrently as listed above.

But the lack of a simple viable piston or turboprop had stunted the rest of our aviation industry (if we bothered to look beyond the LCA and glamorous turbofans.)

Cheen’s industry is selling drones by the hundreds because they have an indigenous turboprop. Their AEW/Elint/MP programs are flourishing on countless propeller Y-8/Y-9 variants. We are held up on our AEW programs by foreigner platforms (with new Phalcons taken hostage by Russian blackmail.) A damn piston or turboprop should be well within the capability of our industry.
Image

I see no hope of us bridging the gap unless we build our foundation and we need to be able to compete in the less glamorous aviation segments held by the simple propellers and turbojets. We must have sources of work and income beyond flagship projects like the Kaveri and LCA. The PRC is selling turbojet trainer/light attack craft like the FTC-2000 or light utility pistons and turboprops like the Y-12 and Le500 in the civilian market.

In fact, more worrisome than the WS-10X series and their supposed super mil engine, the WS-15 Emei, are their forays into the civvy engine markets with the SF-A, WS-20 and especially the CJ-1000A.

The CJ-1000A is being built by a civilian firm ACAE in Shanghai. This is to power their C-919 airliner and it is supposed to be ready in 2018. Once they break into the civilian market with the massive money available there — as well as the feedback loop enforcing reliability and quality — it’ll transform their already formidable military sector. Just like Boeing and Airbus do for the mil sector in the West.
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Re: Kaveri & aero-engine discussion

Post by JayS »

chola wrote: Here goes.


So an analysis of Cheen’s engine experience in relation to our GTRE/HAL/Kaveri comes down to the breadth and depth of their eco-system versus the fragile, thin layer that is ours. The Kaveri proved that ours is one of excellence since getting a modern turbofan to the testing stage puts us in a small select elite. But it is still a thin layer of excellence.
Well said. This is quite apt analysis. While we have had edge in quality (IMHO we can still steal the initiative but we know that even this govt is too lethargic for doing things that it would take) we squandered it by having literally no national interest in building a jet engine. And our Achilles heel has always been lack of facilities of any and every sort, so even those who were working on it could not give 100% output. If you ask me, I am very confident that Indian Engineers and Scientists are quite capable of giving a T:W ~8-9 class engine in a decade if GOI gets serious about it. We have quite a large group of engineers in BLR who have decent exposure to engineering processes from Western MNCs and DRDO has decent high tech base. The two together can take care of design and flight testing. Manufacturing is one area where we are far behind. But if a challenge is given to companies like Kalyani there is no particular reason why we can't do Kaveri class engine in a decade, which does not even need SCBs. Many companies are indeed having decent skill base. Some more efforts can get us there. But it will take National efforts with visionary planning, synergistic working of 100s of organizations and tens of billions of dollars.

Let me say this - unless GOI gets into Mission mode we will never build a jet engine. There is no single fcking country in the world who has developed Jet engine casually like we are trying to do. And the chances that GOI will do that are slim. Even with Modi at helm. So I do not expect even AMCA to have desi engine. If it gets I'll consider it as God's gift to our country which does not deserve to have it.
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Re: Kaveri & aero-engine discussion

Post by ramana »

JayS and Chola, Very good compilation and apt conclusions. One ting that bothers me is since the HF-24 Marut the Achilles heel was always the jet engine. Yet we see underfunded GTRE and siloed HAL Jet Engine division. I am not sure if these two talk to each other. Can't have some many under achievements one after the other if they talked to each other.
One thing I notice is the apathy of user community to this state of affairs. No demand from IAF that they want an engine with so many hours between overhaul etc. Quite content with the pathetic state of affairs.
I was reading about anti-tank gun development in Great Britain during World War II. And the state of affairs was due to disinterest in the Royal Artillery for such weapons. There was no requirements and hence pop guns were developed by the industry.

Similarly in British model R&D and industrial setup if the user doesn't ask for it you get blue sky projects like in GTRE which don't have any application.

The user needs to ask for the goods. The GOI then gets agitated.

I have never seen an IAF officer at the technical level demand a good engine. The chiefs are fighter pilots and will fight with what they got but its at the lower levels (Air Cde, AVM level) they need to be more assertive to support their own fighting force.

One project could be to figure out for the current engines what wears out often and start looking for better parts.

Then procurement scams come in like the Chinese bearings for Dhanush!!!
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Re: Kaveri & aero-engine discussion

Post by chola »

JayS wrote:
chola wrote: Here goes.


So an analysis of Cheen’s engine experience in relation to our GTRE/HAL/Kaveri comes down to the breadth and depth of their eco-system versus the fragile, thin layer that is ours. The Kaveri proved that ours is one of excellence since getting a modern turbofan to the testing stage puts us in a small select elite. But it is still a thin layer of excellence.
Well said. This is quite apt analysis. While we have had edge in quality (IMHO we can still steal the initiative but we know that even this govt is too lethargic for doing things that it would take) we squandered it by having literally no national interest in building a jet engine.
I think it would be more accurate to say we had no interest in doing the needful of funding and building the manufacturing and technological foundation required for building a jet engine.

We definitely had a national program in the Kaveri. But it is like a brilliant teenager attempting to build a car engine in his family garage. So even if he manages to build an example (with help from the professionals at the lical repair shop) he doesn’t have the basic infrastructure or tools to productionize.

Again the Kaveri was very ambitious and we came very close to realizing it. But the material science needed made failure a foregone conclusion without Western help since even the Russians have issues on that front.

The reason for this lacksadaisical approach to the industry probably comes down to the fact we never lacked for advance fully integrated imported maal. Whether it was the MiG-21, Jaguar, MiG-23, MiG-29, Harrier, M2K or Su-30, India had access to some of the top machines of their time. There was never a pressing need to build things from the ground up since we always had access — the Pokhran embargo aside. The armed forces became addicted to high phoren quality compared to local. Open access also made job creation became more important than gaining full control of the technology during negotiations. Hence a continuing series of subcontracting work masquerading as ToT. (True ToT should not end with when the Nth airplane rolls off the line.)

Contrast that to Cheen who under both the Sino-Soviet Split and then Western embargo was forced to build an infrastructure from the bolt up. For their armed forces, it was local or nothing. And they had to go through every rung on the technical ladder from piston to turboprop to turbojet and finally to turbofans.

We went directly to the turbofan because we can always
just go out and buy the more primitive stuff — like a piston for Rustom. But that primitive stuff form your foundation and by their own right are required for other segments of the aviation industry.

In the end, there was no systematic approach to build an engine industry because there was never enough pressure to force one. We could always go out and buy the best currently on the market.

Now on the other end of the spectrum — where unlike India, access to the global market was denied for decades. This is Iran:

https://www.flightglobal.com/news/artic ... at-439418/
Iran will power the Kosar with two “J90” engines, which are a domestic adaptation of General Electric J85 turbojets fielded with the original F-5, Mohammad says.
Image

Image

By cloning the J-85 turbojet from the F-5 (but not the F-110 turbofan from their F-14), the Iranians — to be perfectly honest — have lapped us. The Kaveri is far more advance but it is still in the lab and will be there until SNECMA finishes putting a French core in it . The J90 is being productionized to power the Saeqeh (below) as well as the Kosar shown above.

Image
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Re: Kaveri & aero-engine discussion

Post by JayS »

I don't think one needs to go through all the steps to catch-up that others have gone through. We could have definitely built decent turbo-fan without having even a basic piston engine built, had GOI taken the task seriously and given proper funding. I believe its very much possible to leap-frog by using latest technology available now, e.g. Computational design methods, 3D printing. But one needs careful planning. Given our system, we would have failed in even making a half-decent IC engine as well perhaps. In fact leap-frogging should be used by default wherever its possible. Because we will never have resources and time to go through all the hoops and still be able to catch up. Technologies like 3D printing, Hypersonics, CMCs should have been main focus of our basic technology research today. But alas...

And, yes, easy availability of imported stuff definitely was a big factor. Given total apathy of indigenization at the top, and that AFs had to do their job in any case, the desi programs always took backseat. But I don't consider import as the main factor. Its always have been apathy from GOI. A nationalistic GOI could have used this free access smartly to leap-frog on technology, even without retorting to dirty tricks like Chinese. I liked one thing that Trump said, 'Free market is good, but you need smart leaders for it to be beneficial to you as a Nation'.

Even now we can see dilly-dallying on AMCA funding or Jet engine program. Now time is being wasted and when AMCA is about to come up suddenly we will look for desi engine.
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Re: Kaveri & aero-engine discussion

Post by JayS »

chola wrote: I think it would be more accurate to say we had no interest in doing the needful of funding and building the manufacturing and technological foundation required for building a jet engine.

We definitely had a national program in the Kaveri. But it is like a brilliant teenager attempting to build a car engine in his family garage. So even if he manages to build an example (with help from the professionals at the lical repair shop) he doesn’t have the basic infrastructure or tools to productionize.

Again the Kaveri was very ambitious and we came very close to realizing it. But the material science needed made failure a foregone conclusion without Western help since even the Russians have issues on that front.
Calling Kaveri a National program, is like calling a person, who barely received any decent education till 12th but got admission to a good engineering college with negative score in entrance exam due to our idiotic reservation system, a brilliant person.

Kaveri is not a failure due to material science per se. Its 2.5-3 generations behind the state-of-the-art in the world today. Its doesn't need all the TFTA materials, not even SCBs are needed for it to achieve its design specs. Having access to better materials would have certainly helped, but its not an absolute necessity. Its more related to systems integration. We have some facilities for module level testing, but not much for entire engine as a whole. Modules would OK, but put together they don't perform as expected. And the lack of facilities means the designers do not have enough tools at hand to uncover, understand and debug the issues. You can perhaps add some contribution from bad program management. For example, decision on going for flat-rating, not keeping margin on T:W ratio and stuff like that, which made difficult task even more tough.

Frankly, speaking as an Engg working in the field, simply see no reason why Indian scientists and engineers cannot make Kaveri work if they are given needed facilities and funding to test it properly. How do you debug an engine for flightworthiness without actually testing in in flight..? That's like asking someone to debug a SW only using binary exe, without having access to the source code.
chola
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Re: Kaveri & aero-engine discussion

Post by chola »

JayS wrote:I don't think one needs to go through all the steps to catch-up that others have gone through. We could have definitely built decent turbo-fan without having even a basic piston engine built, had GOI taken the task seriously and given proper funding. I believe its very much possible to leap-frog by using latest technology available now, e.g. Computational design methods, 3D printing. But one needs careful planning. Given our system, we would have failed in even making a half-decent IC engine as well perhaps. In fact leap-frogging should be used by default wherever its possible. Because we will never have resources and time to go through all the hoops and still be able to catch up. Technologies like 3D printing, Hypersonics, CMCs should have been main focus of our basic technology research today. But alas...

And, yes, easy availability of imported stuff definitely was a big factor. Given total apathy of indigenization at the top, and that AFs had to do their job in any case, the desi programs always took backseat. Even now we can see dilly-dallying on AMCA funding or Jet engine program. Now time is being wasted and when AMCA is about to come up suddenly we will look for desi engine.

In theory, yes you can leapfrog. Especially if you are experimenting in a lab. Which in a sense is what we had done with the Kaveri. Leapfrogging in the business world usually means copying someone else advances or simply buying them. In either case, you need lots of money. Leapfrogging isn’t easy or cheap.

At any rate leapfrogging is much harder when you are setting up an actual industry that depends on capacity (infrastructure needed to build things) and capability (skills needed to build things) both of which, again, require funding.

If we had developed a reliable piston that can power that segment then we can build the factory, the production lines, train our staff, set up contracts with suppliers and in general develop the eco-system. Then once set up, we can sell and get into the all-important feedback loop where feedback and income from customers are used to improve your engine, thereby gaining more customers and more feedback and income to improve or develop new products in a virtuous circle. All the while, your staff becomes more and more experienced, your suppliers and supply chain more efficient, etc.

This cannot be done with a turbofan design stuck in the lab that we cannot finish because of tech level or funding. Make what you are capable of technically or financially and begin the process of industrialization.
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