Kaveri & Aero-Engine: News & Discussion

Pratyush · Post by **Pratyush** » 03 Jun 2021 11:40

Critical Breakthrough Brings India One Step Closer To Building Its Own Fighter Jet Engine

I was curious about the Isothermal forging and decided to do some more reading about the topic. Came across the linked article with the following passage.

“Using the isothermal forge press facility available at DMRL, Hyderabad, bulk quantity (200 numbers) of HPC disc forgings pertaining to various compressor stages have been jointly (DMRL & MIDHANI) produced and successfully supplied to HAL (E), Bengaluru for fitment into Adour Engine that powers the Jaguar/Hawk Aircrafts, the ministry statement said.

India had shelved the plans to integrate new engines into its fleet of around 116 Jaguar aircraft whose engines have lost thrust over the years. The proposal to install Honeywell F-125IN engines into 80 of these aircraft was canceled after the government realized the exercise wasn’t worth the huge money since the jets too are to be retired soon.

The Adour engine powering the IAF jaguars has been developed by Rolls-Royce Turbomeca and the Mk 871 variant has been in licensed production with Hindustan Aeronautics Limited (HAL), used also for the new Hawk Advanced Jet Trainer.

“The compressor discs produced using this methodology met all the requirements stipulated by the airworthiness agencies for the desired application. Accordingly, the technology was type certified and a letter of technical approval (LoTA) was accorded. Based on the exhaustive component level and performance evaluation test results, HAL (E) and Indian Air Force cleared the components for engine fitment,” the statement added.

Having read the article the following question comes to mind. Does it mean that the issues that had cropped up due to the age of the Jaguar engines have now been resolved?

Prasad · Post by **Prasad** » 03 Jun 2021 14:24

The current engines are under-powered. That wont change without an upgrade. These are indigenisation efforts.

fanne · Post by **fanne** » 03 Jun 2021 17:15

Jags engine, cutting the clatter

1. Jaguar engine has aged. We have ToT to make it. However, the same engine that is old now, is producing 70% of the thrust that it was producing when it was new. That is the case with most Jaguars, where the engine is old.
2. To quickly add a jump of 30% to 40% thrust over the current old engine output, a new Adour engine (same type) in itself will achieve that.
3. That amount of thrust should be sufficient for low-level flying (almost all of Pak border)- It is doable now. Even there are photos of Jags flying over the fingers at LAC
4.Yes, overall, a new engine like the Honeywell will boost thrust well over a new Adour engine, which could do a lot of wonders to Jags. But given the cost, it is not worth it.
5. Speculation - These new tech breakthroughs are for in-house development and replacement of Adour parts to make it like new and improve on degraded performance. Overall a nice workaround till we retire the jags.

chetak · Post by **chetak** » 03 Jun 2021 18:14

Prasad wrote:The current engines are under-powered. That wont change without an upgrade. These are indigenisation efforts.

and also, their performance has degraded/deteriorated with age and use.

Replacement of major parts with non OEM substitutes will call for extensive ground testing, verification and validation of test results followed by flight trials. The engine parts are flight critical and so much of the testing becomes mandatory.

will the OEM be willing to part with the original test procedures and test results so that a base line can be established for the new tests.

TBO may change and the life of other components may be affected in ways yet to be examined, understood and verified by testing.

effectively it may be closer to a new engine that seeks to replace the older one because of the amount of work that will be called for to get the job done.

that brings us to the trade off between the remaining airframe life and the development costs of the engine and the cost benefit analysis.

fanne · Post by **fanne** » 03 Jun 2021 21:44

It furthers our know how on engine making and going through jags could be the best way to go about it. Being double engine, one engine could be the reworked one which will make it little less riskier

V_Raman · Post by **V_Raman** » 03 Jun 2021 21:49

We have ToT to make the Adour engines used in our Jags!!! That is news to me - how can we say we dont have engine tech then - we cannot make/import some of the parts required?

bharathp · Post by **bharathp** » 03 Jun 2021 22:09

V_Raman wrote:We have ToT to make the Adour engines used in our Jags!!! That is news to me - how can we say we dont have engine tech then - we cannot make/import some of the parts required?

dunno why you are still surprised. we had bofors blue prints for decades, we still dint do much with them.

chetak · Post by **chetak** » 03 Jun 2021 22:25

fanne wrote:It furthers our know how on engine making and going through jags could be the best way to go about it. Being double engine, one engine could be the reworked one which will make it little less riskier

for decades since independence, HAL has been dealing with a multitude of foreign engines, british, russian, french, ameriki and whatnot at the component and subassembly levels.

And again, HAL has been continuously involved in deep overhauls, strip and rebuilds, engine tests, defect investigations, modifications and rectifications.

Why no tangible and/or useable learning outcomes from all those insights into design, manufacture and testing

the russkis took a basic Nene engine from RR, and reverse engineered the Nene to develop the Klimov RD-45, and a larger version, the Klimov VK-1, which soon appeared in various Soviet fighters including Mikoyan-Gurevich MiG-15.

and we in India also had the Nene and that too from two different companies from two countries and we don't seem to have done much with any engine that we obtained from various countries.

ISRO is another powerhouse and repository of engine expertise and certain areas of common interest between HAL, GTRE and ISRO may well have overlapped but left unexploited because of empire building.

so, just like one swallow, does not a summer make, likewise, one blisk does not a new engine make. just saying onlee.

we should be looking at the kaveri much more than the almost end of life adour.

or maybe even a kaveri offshoot/derivative to strike out in a related but slightly different direction

the russkis, cheeni, iranians and the pakis have bribed, honey trapped, corrupted, lied, cheated and stolen at times, bought people and managed to lay their hands on technology they wanted.

is there something wrong with us or what

chetak · Post by **chetak** » 03 Jun 2021 22:41

bharathp wrote:
V_Raman wrote:We have ToT to make the Adour engines used in our Jags!!! That is news to me - how can we say we dont have engine tech then - we cannot make/import some of the parts required?
dunno why you are still surprised. we had bofors blue prints for decades, we still dint do much with them.

one guy had the technical b@!!$ and took the initiative, had the drive and managed to motivate his bright team and against all odds, he delivered Train-18 in an epoch making success and see what happened to him and the Train-18 project.

we are not humans wanting to succeed but Indian crabs in a bucket not wanting to make waves, lest we wind up in the crock pot.

Vivek K · Post by **Vivek K** » 04 Jun 2021 00:02

Zimble explanation saar! Need to improve administration of the country. Paying lip service to swadeshi does not deliver. We must reward initiative and applaud people that fail while taking risks. Indians are risk averse - hero worship success and heap blame at attempts that fail. Question for the gurus, can the LCA can step in and take the place of the Jaguar?

V_Raman · Post by **V_Raman** » 04 Jun 2021 01:04

Work like Train18 can be scuttled due to professional jealousy is beyond my realm of badness in any place - appalling !!

ramana · Post by **ramana** » 04 Jun 2021 07:55

Fanne and Vivek, After Desert Storm, low altitude bombing is hazardous.
Since then mostly standoff LGB and GPS guided bombing is the preferred way.
Jaguar avionics have been constantly upgraded for this reason.

Yes Tejas can drop standoff bombs.
But if you look at numbers Jaguars out number Tejas.

Philip · Post by **Philip** » 04 Jun 2021 12:50

The Hawk-I ( armed Hawk) is being touted as a trainer-cum-light attack fighter which fills the CS/GA role. If its cost is competitive with other firang equivs, after all it is a BAe product, it could meet the req. of delivering munitions onto the battlefield out of range of AAA systems,etc. Brit. Tornadoes took a pasting in GW-1 with their low-level attacks.

Maria · Post by **Maria** » 04 Jun 2021 14:07

Can we create a lengthened and armored version of the HJT-36 (or rather the HJT-39 on the drawing board) with the Kaveri as it is powering it?

chetak · Post by **chetak** » 04 Jun 2021 15:17

Philip wrote:The Hawk-I ( armed Hawk) is being touted as a trainer-cum-light attack fighter which fills the CS/GA role. If its cost is competitive with other firang equivs, after all it is a BAe product, it could meet the req. of delivering munitions onto the battlefield out of range of AAA systems,etc. Brit. Tornadoes took a pasting in GW-1 with their low-level attacks.

most trainers these days come with a limited multirole capability which has been built in by design.

some ground attack capability and COIN role is the way most of these trainer types traditionally prefer to go

Kakkaji · Post by **Kakkaji** » 26 Jun 2021 07:39

Safran considers India engine repair plant after mega Airbus order

France’s Safran SA is considering building an engine-repair facility in India, after winning its biggest-ever turbine deal last month with joint venture partner General Electric Co.

The project would be aimed at customers of the venture, CFM International, which was selected by IndiGo, the nation’s top airline, to supply engines NSE 5.93 % for 310 new Airbus SE A320-family aircraft.

CFM has shortlisted the southern Indian city of Hyderabad and an under-construction airport near the capital of New Delhi as two possible locations, people familiar with the matter said, asking not to be identified because the details are private.

The facility would bolster India’s aviation infrastructure, providing a platform for further growth in a key long-term market for Airbus and U.S. rival Boeing Co. Before the pandemic, carriers in the country were ordering hundreds of new jets -- the May order added to CFM’s existing $20 billion contract with IndiGo to power 280 jets with its LEAP-1A engines.

Shekhar Singh · Post by **Shekhar Singh** » 29 Jun 2021 13:44

Here's our own #India's #DRDO Kaveri engine's variant built with #french #Dassault inputs as per agreement, It's a 1180 kg with 83 KN AF thrust, certification by 2024. #AeroIndia2021 #AeroIndia21

https://twitter.com/Kunal_Biswas707/sta ... 87010?s=19

Pratyush · Post by **Pratyush** » 29 Jun 2021 14:43

The flight certification has always been 3 to 5 years away. For the last 10 years at least.

chola · Post by **chola** » 29 Jun 2021 16:27

Shekhar Singh wrote:Here's our own #India's #DRDO Kaveri engine's variant built with #french #Dassault inputs as per agreement, It's a 1180 kg with 83 KN AF thrust, certification by 2024. #AeroIndia2021 #AeroIndia21

https://twitter.com/Kunal_Biswas707/sta ... 87010?s=19

It is pretty much the same thrust as always. But I guess the impact would be the French help would be towards certification and reliability? I hope it was more than just advice and involved some technology.

Kailash · Post by **Kailash** » 05 Jul 2021 22:25

https://twitter.com/Varun55484761/statu ... 51744?s=19

Can someone please explain the significance of this blisk?

k prasad · Post by **k prasad** » 06 Jul 2021 17:46

Kailash wrote:https://twitter.com/Varun55484761/statu ... 51744?s=19

Can someone please explain the significance of this blisk?

The picture quality isn't great, so I can't tell if its a single-crystal BLISK or not. It doesn't look to be.

Back in 2009, GTRE director had mentioned single-crystal BLISKs as a technology that we didn't have at that time that would be necessary for high-power engines (along with TBC - thermo-barrier coatings, and super-alloys, if I'm not wrong).

At that time, there was very very preliminary research work being done on single crystal blades, which hadn't even approached any level of productionized technology. Integrated Blade & Disks (aka Blisks) weren't even being done, I think. Their small prototypes at that time didn't have the rigidity, strength, or hi-temp abilities to be put on the platform. And single-crystal blisks weren't even on the horizon. The advantage of these being, of course, that they're much stronger, have no extra welding or rivets required (no human-reliability issues), so lower weight + stronger + significantly lower blade vibrations, especially at higher modes which case turbulent flows (much of the Kaveri's issues at that time had to do with 2nd and 3rd order mode blade vibrations).

If indeed they've managed to perfect SC-BLISKs, and have gotten them to a good stage of production technology, that's a pretty big leap forward. Next will be to get them strong enough and cast larger Blisk assemblies. Hopefully TBCs are also at a good stage of development, in which case, the 10 year timeline might actually be attainable for a 95 kN engine, IF Sarkaar and Babu-logs don't screw it up.

Prasad · Post by **Prasad** » 06 Jul 2021 19:56

Kailash wrote:https://twitter.com/Varun55484761/statu ... 51744?s=19

Can someone please explain the significance of this blisk?

These are cast as blisks for use in the STFE for the Nirbhay.

I'm not even sure you can make a SC-blisk. Can it be done?

maitya · Post by **maitya** » 06 Jul 2021 21:05

Prasad wrote:
Kailash wrote:https://twitter.com/Varun55484761/statu ... 51744?s=19

Can someone please explain the significance of this blisk?
These are cast as blisks for use in the STFE for the Nirbhay.

I'm not even sure you can make a SC-blisk. Can it be done?

Trouble with the answer to above, is it's not a overwhelmingly No ... as theoretically you can have SC casted blades "joined" to a powder-metallurgy based disk hub using LFW etc, to have a HPT blisk (or the scientific term "Integrated blade and disc").
But the thermal stresses that the HPT blades and disks have to withstand are so dramatically different, that there's no reason why one would want to have SC casted etc disks (doesn't make any sense) - the mechanical-strength attributes are also almost entirely different between them.

But, then again, the above is all true for Super-duper Turbofans with 1400-1500-1600deg C TeT etc regimes (like Kaveri).
So in such cutting edge turbofan applications, blisks are almost entirely focused wrt HPCs* etc (biggest adv is weight reduction, followed by thermo-mech durability considerations wrt crack initiation and propagation etc at the blade-hub joints etc - but intricate internal cooling passages of the blades and then "joining" them to hub of the disk etc can't be implemented if HIP etc is used to manufacture blisks).

But if one is creating Turbofans in 600-700 deg C TET-regimes (like in STFE etc), then yes blisks is a very strong use case for HPTs etc, no doubt. For a simple reason, that ambient temp regime of HPCs in these super-duper turbofans are very close/similar to the TeT regimes of these turbofan applications. Also these HPT blades can operate without convective cooling provided etc.

Maybe these images are referring to such an HPT application.

*Pls refer to Kaveri saga thread for a more detailed analysis of blisks wrt HPCs.

Rahul M · Post by **Rahul M** » 09 Jul 2021 03:10

Thx maitya, very interesting.

hnair · Post by **hnair** » 02 Aug 2021 22:32

Curious Droid (ignore his glorious shirt and Lord Varys vibes if you can) has this nice video about RB211 and its troubled journey, which ultimately lead to success.

Explains how mission creep almost killed it. And this is from a storied firm that made such things like Merlin and has engineering prowess since the dawn of aviation. What seem to have made the difference in a ranking order:

1) Prompt action by Whitehall babus to rescue the firm at the worst juncture (1971), in comparison with our somnolent ones in N/S Blocks
2) The role of outstanding old timers (who were bought in from retirement) like Stanley Hooker in keeping a steady hand on the program management side, so the redesigns actually exceed the expectations
3) Deft business negotiations by pin-stripes and bowler hats, with the 800 lb LM folks
4) Good PR on the Qantas story

Key takeaway for India
1) If RR faced such issues despite being a literal powerhouse that solved issues of a world war, then Cauvery's lesser than spec thrust issues seem solvable and infact can be exceeded, when one listens to the methodical way that Hooker did it
2) Ability to shield such core teams from turmoil - such programs need the entire national establishment behind it (not just political class or military)
3) The benefits of having lots of test-beds for trying out various sub-component designs, materials etc. Over a decade or so ago, the now wintering Yak-herder has talked about having a few Cauvery based test beds in major aerospace colleges of India. If it can be headed by retired GTRE tech folks of repute, would be excellent way of training up a generation as well as fixing kinks in a parallel fashion

Pratyush · Post by **Pratyush** » 03 Aug 2021 11:21

I was listening to it on my drive home on Saturday. I thought it belonged here. But completely forgot about posting it. Once I reached home.

The remarkable aspect of the story is the fact that RR was making a civilian engine without any pre-existing military order and they had the plan and the design to do what needed to be done for the civilian market.

Even though the execution was troubled at the start. They persisted with it and ended up with a world beater.

I guess that this is the difference between a world power and a wannabe.

A world power will keep going and finish the job. By making it a national mission. The company and government acting in unison.

This is the spirit that is missing in case of Kaveri.

We need a national gas turbine mission. No one will help us develop this engine for us.

Indranil · Post by **Indranil** » 18 Aug 2021 01:38

In 2016, HAL had issued a tender for D&D of a single spool turbojet engine.

Top speed:0.85M
Thrust: 320 daN
Dia: 310 mm
Length: 740 mm
Operating altitude: SL to 8.5 km
SFC: <1.175 kg/daN-h
Restart capability
Endurance: 1000 sec
Dry weight: <44kg (Excl. LRUs & cartridge Starter)

The plan outlined then:
- 2 TDs manufactured at HAL
- 10 engines for quals/certifications (first 3 built at HAL, rest with private sector)
- 5 LSPs
- Init. prod rate (first 2 yrs): 6 per annum
- Requirement 250 engines over 5-6 yrs.

Step 1 of this plan is now commencing. The 2 TDs are entering rapid prototype stage (guided by GTRE). The specs with regards to the engine dimensions seem to have been met.

Length~700. Diameter ~250mm.

Question is: Will RCI stay the course of its 275 kgf engine with NAL. The above engine is quite close in specs.

Prasad · Post by **Prasad** » 18 Aug 2021 01:58

What's this engine for?

Indranil · Post by **Indranil** » 18 Aug 2021 03:47

Don't know. But when they say "Endurance:1000 secs", and engine starting capability at 0.4-0.8M, it points at an ALCM with a range of about 300 km range. Expect a weight of about ~500 kgs

Prasad · Post by **Prasad** » 18 Aug 2021 12:20

Rakesh · Post by **Rakesh** » 18 Aug 2021 19:45

https://twitter.com/hvtiaf/status/14278 ... 83685?s=20 ---> Just FYI...In India, we have manufactured more than 5,000 military aero-engines & overhauled more than 35,000 military aero-engines.

Varoon Shekhar · Post by **Varoon Shekhar** » 18 Aug 2021 20:30

^^

Excellent! How much indigenisation has occurred in these HAL made engines?

Indranil · Post by **Indranil** » 18 Aug 2021 20:37

Is it far to say that HTFE and HTSE 1200 are the results of manufacturing the Adour and the Shakti engines respectively. I hope they also build an HTPE (Hindustan Turbo Prop Engine) based on their learning of producing the Garrett engines.

Rakesh · Post by **Rakesh** » 19 Aug 2021 23:36

KPS really needed to be put in his place and it finally got done.

https://twitter.com/realkaypius/status/ ... 21834?s=20 ---> Are we supposed to celebrate this? The govt should shutter GTRE & sell the land on which it stands to fund this extravaganza. Building castles in the air on imported engines; doling out billions while keeping an inept establishment on drip feed. #AtmanirbharBharat?

https://twitter.com/hvtiaf/status/14281 ... 62115?s=20 ---> If Test Pilots also stop understanding challenges in core research like aero-engine design, Indian R&D is doomed. Difficult engineering problem; designing a high-thrust jet engine. Shutting down a research lab, because we can't have patience, speaks poorly of testing community.

https://twitter.com/Firezstarter1/statu ... 34630?s=20 ---> Plus the Manik which is now powering the Nirbhay, shaping up be a critical system, owes its heritage to the Kaveri. The engine likely to power the heavy UCAV programs will be a "dry" Kaveri derivative. Cant throw away all this hard won expertise!

https://twitter.com/i_udit_t/status/142 ... 69701?s=20 ----> Also the naval variant derived from Kaveri engine: 12 MW marine gas turbine engine is doing fine and will be used to propel naval craft in near future.

Vivek K · Post by **Vivek K** » 20 Aug 2021 01:54

What baloney! Glad he was put in his place by HVT Sir!

kit · Post by **kit** » 20 Aug 2021 02:00

Rakesh wrote:KPS really needed to be put in his place and it finally got done.

https://twitter.com/i_udit_t/status/142 ... 69701?s=20 ----> Also the naval variant derived from Kaveri engine: 12 MW marine gas turbine engine is doing fine and will be used to propel naval craft in near future.

In case anyone is interested LM 2500 in its original version was 16MW and successive versions improved upon it., good going

Vips · Post by **Vips** » 20 Aug 2021 19:07

Wasnt a derated Kaveri version also proposed for powering Railway locomotives?

chetak · Post by **chetak** » 21 Aug 2021 00:00

Vivek K wrote:What baloney! Glad he was put in his place by HVT Sir!

there is the sly and needling play of the politico in most of what this character says. He has an agenda.

his tweets sometimes get picked up and retweeted by martial dinosaurs and that has gone to his head.

good to see that someone knocked him off his self assumed lofty pedestal

chetak · Post by **chetak** » 21 Aug 2021 00:05

Vips wrote:Wasnt a derated Kaveri version also proposed for powering Railway locomotives?

the economics may make it unviable.

likely fuel options are LNG or diesel and maybe mated to a generator and running at some constant RPM.

mody · Post by **mody** » 15 Sep 2021 13:33

https://www.msn.com/en-in/news/other/ha ... hp&pc=U531

HAL and RR sign MOU for Adour engines parts and MRO facility. Unfortunately I feel this is 20 years too late. Anyways, might help HAL get a few orders to supply parts for Adour engines of various models.