LCA Tejas: News and Discussions

saumitra_j · Post by **saumitra_j** » 14 May 2015 08:59

UB Sir, point very well taken. GTRE's credibility is as good as good as Pappu's understanding of Indian problems and politics. However I would still give them some support to finally finish what they started.... kaveri is already delinked from the Tejas and is now a purely a science project....of course one may not believe anything that gtre says and kill the funding..afaik, goi continues to fund gtre...so may be they actually are at a level which the claimed to be 20 years back. I completely agree that we should do what it takes to build an aero engine and your idea of a turbine without stators must be picked up...except that it should be done with the academia in a national mission mode. Kaveri on the otherhand would still be useful to reengine lca mk1 by tge time it is certified...the current sp1s would reach mlu stage by tge time the current Kaveri is actually ready....writing through a cell phone...will write in details later.

deejay · Post by **deejay** » 14 May 2015 09:06

ramana wrote:Deejay, Thanks.

As PRC moves West, IAF needs to move South.

IAF is moving in a lot of its frontline Su 30 MKI sqns to the North East. I was surprised when I visited Chabua last October. Honestly, EAC - Eastern Air Command was called the Eastern Air Circus, not any more.

hnair · Post by **hnair** » 14 May 2015 09:45

prasannasimha, you are banned for a week, for name calling. If you dont understand, ignore such posts in future or if it is offensive, report it.

Anyways, for those still having thoughts (or lack of)

ramana wrote:Shreeman and others, You don't have UB's compulsions to use pingrezi.

So please desist.
Only UB and Vina may use it.
Thanks,
ramana

UB and Vina carry on.

shiv · Post by **shiv** » 14 May 2015 09:50

I used to know a Brofsar who used to make sensible baats under his own naam. His biggest crime was living and teaching in a land where terrorists have equal rghts. One day a cousin marryer discovered who he was and started making trouble for him. The man went off BRF because it was no longer possible to post sense without Googal chacha allowing Bulbuddin to do word search and make IEDentity konnekshun and do gol maal in equalopportunityforterroristsland. Old timers on BRF will remember.

If beepals show patience rather than oiseaulegiri we will all learn.

hnair · Post by **hnair** » 14 May 2015 09:59

Shreeman · Post by **Shreeman** » 14 May 2015 10:35

hnair wrote:prasannasimha, you are banned for a week, for name calling. If you dont understand, ignore such posts in future or if it is offensive, report it.

Anyways, for those still having thoughts (or lack of)

ramana wrote:Shreeman and others, You don't have UB's compulsions to use pingrezi.

So please desist.
Only UB and Vina may use it.
Thanks,
ramana

UB and Vina carry on.

Leave me out of this one folks, not a deserved leader of any trouble makers -- both on the pingrezi and compulsion parts. I am happy to go, not think for a while:

Doing the least appears to be the best way of achieving greatest impact --unknown.

vina · Post by **vina** » 14 May 2015 10:45

Ok. Lets get back to the point.

Indranil, this thread will need a clean up. Do put all the Yinjin related stuff into the relevant thread .. No don't call it Kaveri, just rename that existing thread as "Pumps Turbines and Compressors" thread. Atleast that way, only those who know what they are talking about or atleast are technically inclined, rather than doing R&D (rhone & dhona) above Kaveri /LCA/ etc will even go there.

Anyways.

Mongolian asks, why no one make large drum of 1 m dia ghumaoing at 10,000 arrpm with plades sticking out inside towards the centre like an inverted porcupine quill after all these years. I answer, queschun is not making , but making it stable while ghumaoing.

Until last year, we had a fine piece of Jurman Engineering , an IFB/Bosch washing machine, front loading, with a horizontal stainless steel drum. Work of art. When working fine, running at dus precent of dus hajaar rpm, whisper silent and smooth as hema malini's cheeks . But the moment, there is an imbalance, a few clothes get clumped and dumped in a pile instead of one by one by the maid, or you put a couple of large ones and machine partially loaded, the entire machine used to to dang... dang... violent racket, threatening to rip itself apart, jumping up on it's stand and threatening to fly off like a Paki raakit mad, and all excited and ready to do soosai like a packee who has spotted an ahmadi, especially in high speed centrifuge drying mode. Now mutliply is 0.25 meter thing by a factor of 5 and mutliply pressures inside multi fold and porcupine line quills poking inside towards a centreline shaft with a tolerance of a few millimeters, you are asking for deep trouble.

Well, after the Jurman machine embraced shahadat last year, we got an Amriki washing machine, Whirlpool, top loading, with vertical stainless steel drum, with washing impellers loaded on a central hub standing up and poking outwards. No problem with viprashuns, dump whatever you want however you want,machine silent and does it's job. enough clearances the procupine like quills never touch the sides, the side drum can vibrate all it wants, you will be fine. That is why I think the doosra is a lower risk approach, works well, can be developed modularly independently of the garam parts, tested separately , allows itself for incremental development , basically a lot of applied YumBeeYea giri.

ArmenT · Post by **ArmenT** » 14 May 2015 11:30

vina wrote: Anyways, one the more illustrious members of my extended Phamily (dhoti wearing, going to Maharaja Kallej to gain some Knaalij, mom's /Trivandrum good side, who landed up in Kaliphornia in the 40s, after IISc in Bangalore under CV Raman , misphorchunately, I come from the black sheep side) who got Pacchidee under Theodore Von Karman and also the Iron Maiden /Heavy Metal Fan's dad too got Pachhidee under the same said gent, don't remember hearing the "dark/fascist" side of said gent, only the brilliance, and of course his work from all the textbooks.

Anyways, Heavy Metal Fan's dad taught the course where I learned liphting line theory, dog- Joo cow sky transphorm etc. Grateful as ever of course.

I'm pretty certain I can guess who the second gent is, but can't really guess the first one right off the bat. Perhaps I can ask the second gent about the first one, as he is visiting soon enough. I know the Mongolian yak herder definitely knows the second gent because he's mentioned him by name earlier here, didn't know you knew him as well. Small world.

vina · Post by **vina** » 14 May 2015 12:02

ArmenT wrote:I'm pretty certain I can guess who the second gent is, but can't really guess the first one right off the bat. Perhaps I can ask the second gent about the first one, as he is visiting soon enough. I know the Mongolian yak herder definitely knows the second gent because he's mentioned him by name earlier here, didn't know you knew him as well. Small world.

Second gent was an Armenian from Glendales/Pasadena area who went to college in Pasadena, but rumoured to be able to converse in Bengali (probably family had roots in the Armenian community in Calcutta?) . 2nd wouldn't have personally met the 1st, though would definitely know of him. Ramana knows the 1st gent. Ask him

Karan M · Post by **Karan M** » 14 May 2015 12:53

Ulan Batori wrote: Places like GTRE, sorry to say, are pathetic examples of wasted opportunity. So, it appears, is most of ADA. I know someone who went there to present and discuss something on the LCA. The aero/CFD experts presented their problem: drag predictions not matching flight tests.

As he was coming out, these experts followed him - with CVs ready, asking for assistantships to go to Phoren. So much for dedicated 'scientists' and 'researchers' working to make Indian engines and aircraft better. Simply put, they are just pretending, not serious at all. Of course there are exceptions, just as there are non-terrorists in Pakistan. About 1 in 100. The rest are worse than having no one.

Sorry, but why exactly are the yak herders who followed their dream surprised that there are other people willing to follow their dream and move to land/s of better opportunities? Fact is no matter how many salaries may zoom or funding be great etc as mentioned above, they are still behind worldclass levels and with inflation, cost of living & pathetic standards in terms of law enforcement, basic quality of life issues factored in, patriotism alone won't cut it for many. In short this is what you get if a bunch of folks (significant sections of the Indian populace for a better part of a century) were conned into or were silly enough to elect a bunch of dynastic crooks for 60 odd years who mismanage the country and make it their personal fiefdom. Occasionally the flag was woven for some national level stuff (1971, 1962) otherwise the looting went on unabated. Meanwhile, India can now be visited by somebody from Rwanda Burundi and be told by a straight face, why why do you people make raakits but not proper roads hain jee?

As a result, even people who are better off or are more educated etc will seek to jump ship.

This fire in the belly stuff in the 70s vs beebuls today is all very well, but I daresay there are even more people with fire in the belly (zimble statistics, larger population and wot not) but they also have access to ze internets, travel and are not willing to put up with platitudes of "oh poverty is good onlee yaar, india is poor country, luxury tax on xyz" - soliloquy politician who zips around in BMW with z++++++++++ category security. And hence they seek to move.

Cribbing about ADA etc is besides the point. Most folks in ADA whom one interacts with are ok folks and committed to their job. They are however in a system which a) limits their flexibility b ) regards every Rs spent on LCA as taking away something from poor people (or rather populist schemes which will ensure dynasty team would continue to win elections, results be darned) c) makes sure that no matter what they do, they get a lollipop whereas fighters or systems which cost 100x upfront are discussed for acquisition while jarnails and baboos visit them and tell them they really are wasting money on building useless infrastructure and reinventing the wheel, wot, wot? When ADA guy goes to HAL to plead his case he is told a) LCA is important but not that important because there is Sukhoi, there is the MMRCA B ) HAL comes under MOD so don't try throwing your weight around, they have better lines to the top (after all HAL's choppers and wot not are used by babus and politicos as private transport, hain ji!) and C ) why exactly are they getting so tense after all, its not like IAF really wants LCA, they want more Sukhois and MMRCA etc etc etc.
ADA babu goes to GTRE, he is told a) there is no ready engine b ) original babus who started engine program mis-underestimated program cost by 10x. c) GTRE needs pee-chaddis to do the research work but but since GOI circular bla-di-bla does not allow for pee-chaddis GTRE has hired cheaper injunneers and EmTechs who ...err... need mentoring and perhaps in five years time can turn out anything useful for the program. Meanwhile aforesaid people want "Indian lab onlee yaar" on CV and time to write GRE and move to bhest. d) Big boss who is approached says.. I want to be schientist H onlee.. otherwise I move to R&D center set up by Jee-EEE they are offering me big house, plus sooooooo much money. After files are moved by babus. He moves anyway.

When grumbling ADA guy leaves his campus swearing at the system, he is stopped by potbellied bungalores phinest who says no helmet saar, please give 100 or pay fine saar. Mamul onlee saar. He reaches home after backbreaking ride on potholed road onlee to be told by bhife. Where were you since morning, no bijlee onlee and no UPS. Mummy told me to marry that pvt sector guy working in Oilcompany, at least he would have stayed in flat with battery backup, meanwhile munna needs to go to that school have you arranged capitation? Meanwhile ADA guy grumbles on how so and so connected non ADA guy managed to get his hands on the allotted flat and what not in township... and so life continues.

So blaming the ADA guy is pointless. Look around any Indian metro and there are many hughly educated beebuls To the D, they are mostly managing things by a) copying whatever the bhest does and b) claiming they are egg-sperts by saying they have either phancy education or are expert in what some gora developed. They are then treated as lords by a populace which doesnt know any better and is desparate (India is a classic example of underserved market). In such a milieu, where people who take this risk averse path are minting hand over foot, the guys who do reserach wagehra are second class. They are held in judgement by a) journalists who did some phokat ka social sciences cr@p in furren b) babus who can't distinguish or care between a motor and a mortar and say trails for trials c) politicians who go abroad on furren junkets and preach virtues of poverty.

So.. in such a system, there will be people who give up. Frankly, not all of them are glory hunters or greedy either. Incidentally, things were better a decade back. India story was happening, people were moving back (beyond usual reasons of family etc) and there was a buzz in the air. Hope is current Govt recreates that buzz and things (tangibly) improve so things look up.

maitya · Post by **maitya** » 14 May 2015 17:09

Guys let's not diss the Strategic solutions what Ulabatoriji continues to profess - contra-rotating stages etc (and not sure why he has not talked about variable-cycle engines yet though). These are all high-gain (but very-high-risk) endeavors which if successful, you simply skip/leap-frog two gens of turbofan tech, and that's solid 2-3 decades of back-breaking and very expensive R&D and Testing effort.

Without such endeavors, there's no hope catching up with the best-of-the-west - as incremental advances (as I'll detail out a little later) means by the time we are F414 levels, F135 stuff is already obsolete in the western world and science-fiction stuff like solid-ceramic-turbines etc will be passé.

However risk is, failure means there's no fallback option of slightly-old-gen-but-still-somewhat-contemporary turbofan solutions at hand.

So IMO both strategic tech-leap-frogging stuff like C-R rotor stages etc and tactical incremental advancements are both required.

Ulanbatoriji (and vinaji) have put forward quite a detailed concept-map for the strategic aspect of it - let me take a stab at the tactical incremental path.
==================================

Allow me try to and do that by answering Gyanji's question in sada Ingliss ... "Is there a new Engine proposed by GTRE (~110-115 kn) similar in size to GE F414 i.e would it ever be drop in replacement in LCA or AMCA?"

This question can be broken up into two sub-questions, if you will:

1) Is there a follow-on to Kaveri-I engine?
(Kaveri-I: The one which is ~115Kg overweight, achieves design-goal-dry-thrust of 52KN, but falls short by about 10% of the Wet Thrust design goal of 81KN etc).
Now those figures would have been enough if the LCA MK-I weight would have remained at 5.5Ton ... clearly it didn't (due to scope creep etc) and thus the IoC level
MK-I will be powered by a slightly higher powered F404-IN20s (with ~54kN dry and 89KN Wet).

But the twist to the story is, IAF wants a even heavier platform, MK-II for which they have asked for 98KN class engine F414-INS6 (58KN dry and 98KN wet).

So there's no hope of Kaveri-I coming anywhere near to Mk-I, let alone Mk-IIs ... in military turbofan technology landscape graduating from 80KN to 98KN class is a whole new engine gen (example, ironically is, F404 to F414 ... hope you are aware F414 started as a result of "uprating" requirement on base F404, so minimal core touching etc happening in the initial days of it's development).

2) But what's the tactical solution to all these - is there a way, and granted it will be incremental, of us getting a 98KN (Wet) class turbofan WITHOUT any substantial weight gain (say max 15-20% more allowed)?

(contd ...)

Karan M · Post by **Karan M** » 14 May 2015 17:17

Maitya wrote:So IMO both strategic tech-leap-frogging stuff like C-R rotor stages etc and tactical incremental advancements are both required.

Agreed, but who's going to bell the cat. IM(H)O, right now & for the next five years GOI will continue to try and put the economy back on track & 90% of defense available money is just going to go for the Army, AF, Navy and their crazily expensive committed capex. Each imported thingmajig and its spares cost tens of thousands of crores.
Hope for the best..

maitya · Post by **maitya** » 14 May 2015 17:18

[Part 2]
To that end, if you look at the links at the previous page, there are already some bits and pieces in place - in my mind the incremental steps needs to be:

Step 1) Baseline the basic Mechanical/Thermodynamic turbofan design - Get Kaveri K9 (or whatever they call it nowadays) version into 1st subsonic, then transonic and finally supersonic flight testing regime ASAP. For this you will need a twin-engined platform (of similar air-intake design) and finally a few LCA TDs/PVs to be dedicated for it.

Pls refer to this chart once again ...

Step 1 means you are basically baselining the 4th column from the left (in light blue) performance figures.

Step 2) Show some improved thrust figures via some quick-and-dirty methods to impress End-users/Mango janata and netas: Get the Dry/Wet Thrust upscaled via slam-bam approach - aka increase the mass-flow by changing the dimension of the intake and Fan diameter and also tweak the BPR a bit - but keep the CORE (Kabini) exactly same, thermodynamically, as it is now.

To this end, there's already some initiative, circa Jan'15 - refer to this post from indranilroy - here - Breaking News: GTRE's next engine

This will require some amount of weight saving as well, to mitigate the weight creep of the larger fan, which can be achieved by moving to a CFC based Fan stage etc. Right now the Core of the Kaveri Fan stages are Ti based (and there are 3 Fan stages in total) and is the heaviest single component on the engine. The mass-flow to the core will remain same, so overall higher mass-flow to the engine, will have to be compensated for, by increasing the BPR.

All the core components, like HPCs, HPT and LPT etc will require minor increases, but not much change in the thermodynamic aspects of the core. The resulting engine would have a somewhat dramatic increase in o/p thrust levels (if you go my sheet in the previous page, the ballpark figures would come to 88KN/123KN Dry/Wet levels), which roughly would be comparable to 414 levels.

Referring to the above chart, this means achieving the 6th column from the left (the 1st light red one) performance figures.

However, all this showbazzi will reduce the efficiency of the engine mind you (so higher SFC etc) ... but hey you will have something to show for (IAF will not be impressed, but since they will never going to be impressed anyway, barring a shiny videshi sticker on it, why bother).

On a pen-paper theoretical levels it should be enough for AMCA/LCA-MKII etc ... but we all know what will be IAF's reaction to it, so no joy there!!

(contd ...)

maitya · Post by **maitya** » 14 May 2015 17:24

[Part 3]

Step 3) Bring next Gen Compressor material tech - and get the weight issue of the baseline K9 series resolved somewhat.
This is where things will get interesting - as reducing weight, means tweaking the core itself (huge risk and huge re-testing effort). Some amount of weight-saving can come as in step 2 itself (by moving to CFC based Fan stages, in all 3 of them) as elaborated above.

But the critical aspect is looking at the alternate material tech for last 3 HPC stages (aka stage 4,5 and 6 - as opposed to Ti based HPC Stages 1, 2 and 3) - they are all currently made up of equiaxed Ni based superalloys. This since the ambient temp gradient breaches 550-600deg C from around these stages - Ti blades will simply melt/or-atleast deform at those temp (and mech stress levels).

So to withstand those thermal and mech stress levels one had to resort to the heavier equiaxed Ni-superalloy based casted blades (and matching wrought disk) from INCONEL-718 (called GTM-SU-718, refer to Kaveri sticky for composition details etc - basically a Ni-Cr superalloy) - but Ni-superalloys are heavy as they have higher density (and thus weigh more for the same volume or geometry), making the overall engine overweight.

So, one of the solution is to bring in either better materials or better cooling tech or both.

Step 3a: Titanium Aluminide: On better material front, the current trend is to go Ti-Al (Titanium Aluminide) which gives temp tolerance levels of 750-850 deg C, enough for last-stages of HPCs (actually also used in LPT of nextgen civilian turbofan applications, but that's a diff discussion).
But the best part is the density aspect - a Ni-Cr superalloy like INCONEL-718 has density of 8.19gm/cm3 - while Ti-Al alloys average out at 4gm/cm3, a straight approx 50% weight saving of the compressor stages.

All good, but why nobody has done this yet in GTRE ... well, 1st answer cost, 2nd answer is who is going to hand over us the EBM machinery/tech required to get this done (the tech is about, from a lay-man pov, melting metal powder layer by layer with an electron beam in a high vacuum).

Ok, any other alternative method, you ask?

Step 3b: Better Cooling Tech: This beast is all about applying the paper-designs of intricate serpentine air flow paths, that you'd see normally in the turbine blades, in the compressor (last couple of stages) blades. Easier said than done ... because of variety of reasons.

But pretty recently GTRE folks were having trouble in producing aerofoil shaped, sintered silica cores that will be useful in producing the hollow cooling channels in the HPT/LPT blades/vanes and LPT blades - so getting them imported from Safran or Snecma (can't remember exactly).
Now for compressor blades this tech (of CIM - ceramic injection moulding etc) goes to a next level in complexity - for you can't simply dump the heated air into free-stream between the blade-stages, you need to bring it back to another channel within the shafts to drain it out to the combustion part of the engine.

Until very recently giants like GE were struggling with this but have been finally successful - where GTRE guys, as of 2011, were at demonstration-stage of this tech for the Turbine blades (and also trying to adapt the same tech to Alumina-cores for SC applications).

Getting these two aspects sorted, would amount to technological re-baselining of the core (Kabini) to a level where, one can still call it contemporary - but still not with adequate thrust levels of Pt.2 above.

Referring to the above chart, this means achieving the 5th column from the left (the deep blue one) performance figures - notice how TeT and OPR has gone up, and so has the raw performance figures (but more importantly, this performance improvement is not a the cost of the Thermal and Propulsive efiiciency figures, depicted towards the end of the above chart).

Step 4) Last step is to take this technologically re-baselined Core and infuse further technological advances like wide-chord compressor blades, 4+ Gen SC blades, compressor blisk stages, advanced themal-barrier coating, CMC for turbine-rotor parts etc etc ...
aka take the more-massflow-via-bigger-dia-engine from Pt.2 above, applying the critical tech developed from Pt. 3 above and then re-applying the cutting edge stuff like wide-chord compressor blades, 4+ Gen SC blades, compressor blisk stages etc.

And finally you will have something that can come close to what IAF wants today-now in terms of a military turbofan.

Referring to the above chart, this means achieving the right-most column performance figures - you may want to compare the efficiency figures with that of the column right before it to understand the scale of improvement this brings.

(contd ...)

maitya · Post by **maitya** » 14 May 2015 17:29

[Part 4]
Now question is how does all of these will get achieved, if at all?

Any self-respecting nation would have simply pumped more funds into and made it fly in sqn services, irrespective of these thrust shortfalls ... for a simple reason, that ab-initio building-up 4th Gen military Turbofan capability is something once-in-a-50yr-deal, you simply do NOT squander away the learnings.

There's only so much you can test (there are infinite permutations and combinations of throttle, thrust, drag, altitude, bank-rate, climb-rate, AoA ityadi ityadi settings) - and the only way to build up a set of parametric equations and other what-if models etc is by simply flying it for thousands (if not millions) of hours.

Not possible to achieve with piddly one or two flying-test-platforms.

So despite the various incarnations of Lun-Lun/Tun-Tun failing repeatedly in high-altitude testing etc, Chinese throw in that much more funding to it, to precisely build that Knowledge Repository (by 1st making a prototype fly and then force their AF to accept sub-par engines in their platforms and build up that experience).
It might take a decade to continuously refine the core and reach a certain maturity level (aka the turbofan Knowledge Repository), and voila you have Lun-Lun-IIs and Tun-Tun-IIs comparable to the best that western were able to field.

That's precisely what happens all over the world - for example in US where a F414 gets developed from a F404 core.

That is called national capacity/capability building for which two things are required - a "fiercely-independent" mind void of any log-kya-kahenge distractions and perseverance.
Everybody knows nobody would part this Knowledge Repository to you - so you can do as much of assembly-giri of AL-31FP etc, when it comes to fresh-sheet design of a next-gen turbofan, who start from a big-anda level!!

Pls draw you own conclusions wrt attitudes displayed by India in general and MOD/IAF/GTRE-and-other-assorted-bondabosts in particular.

So, last I heard, in some newspaper report here in BRF, that GTRE folks have been asked to build up the required hrs (IIRC ~600hrs still left) in testbeds before it can be certified to be flown in a double engined aircraft, say MiG-29 (and neither is there any capacity/funding to build high-altitude testing facility in India).

After which the hunt of double-engined-platform would begin - and no IAF wouldn't loan any of their precious tactical-platforms for such "science projects" (immediate triggering of the wailing-chorus of "depleting squadron numbers" etc).

Once triplicate-form-filling and chai-biskoot-sessions are done in x yrs time frame to get that double-engined-platform, will it require approx 1K hrs of solid flying before being certified for integrating in a single-engined platform like the LCA TDs.

A very long and difficult road to trudge along - but trudge we must, if there's any hope of achieving indigenous turbofan engine tech maturity.

(the end)
Sorry for the long ramble!!

UlanBatori · Post by **UlanBatori** » 14 May 2015 17:32

Karanji, apologies, it is always the good ones that read and get hurt, I know. We do what we can. But as for all these 'difficulties', there are parallel or worse things everywhere else. See F-35 dhaga for some present glimmers. I don't know how good people stay sane at NASA either. It's actually much better these days to be in Indian establishments, but I have no interest in a whinefest on "Who Has Worse Management?"

But getting back to LCA, I think drastic movements are needed by the aerospace leadership in India to save it from becoming HF-24(b). In those days we had great dreams for the HF-24. Look at it! What a beautiful plane! All Indian! Makes a great wallpaper.
Why? Because there was no engine. (OK, canopy flew off and killed a couple of pilots, but the program got over that too.)
The pity is that for all the yada-yada-yada in the media, I cannot point to one sustained campaign DEMANDING that India advance engine tech. It's always : Which engine can we buy? Which is why, if you want to work on developing engine technology for India, it is probably better to be in Botswana Institute of Propulsion or Rwanda Turbomachines Inc.

Note what has evolved above: Now the GTRE KAVERI is being defended as an **academic** exercise, not as the Next Big Hope. This is saddest of all. Reminds me of the picture on the front of Young Pioneer magazine, which was given out free by the USSR Consulate back in the 1960s.

Soviet Young Pioneers pose in front of the electric railway engine that they built by themselves

To have any hope of going beyond the present, India needs 3 or 4 competing, well-funded, well-staffed, well-led propulsion R&D units. My advice is to set these up as autonomous Centers co-located with IITs because you can get a lot of free brains and enthusiastic effort. But one has to have people who know how to break down a highly complex endeavor into micro-pieces, get them done by yaks, and then integrate/ synthesize them with a clear schedule and aim of developing top-notch engines, not just publishing papers. No disrespect for publishing papers, it ain't easy, but the optimization is different from programs optimized to generate working hardware. Both the quality controls of peer-reviewed publication AND hardware implementation are needed, which is why I say "Centers" not "Professors" or "Academic Research" or "Applied Research" or "VC Incubators" or "Government Labs". All must be integrated.

(also note: University-based centers could be occasional Open Meeting Places between people working on Open-Literature Civilian places and in ***No Such Program** places. Avoids lots of issues)

Just imitating US model or Russian/ Oiropean or Burundi models is not going to achieve anything (for the above reasons) but appearances and conference PPTs. Look at how the IGMDP was done - at the core there were really good and dedicated people, which is why Akash has become operational. They knew what to ask from the universities and from elsewhere. At least on that one, I know quite a bit about the startup process (of the project, not the weapon) more than the aam Mongolian news agencies know, so I understand the difficulties quite well.

LCA has excellent flight control, IMO. This can be traced back to excellence at some Indian institutions (not that the labs aren't involved - they are, but the people there came from, and continued to interact with, the schools, and the research at the schools was good - I've seen the papers). The aerodynamics is OK - it would appear that much has been learned from HF-24, Gnat, MiG-21 and Mirage-2000, and IISC wind tunnels have helped learn those. Structures is OK, you can trace that back to investment in FRP back in the 1970s in IITs etc, but I think they did not advance to keep abreast of the Japanese automobile industry's huge advances in composite manufacturing (I suspect a certain amount of prejudice and west-kissing here). In the rockets area, fantastic advances have been made in solid rockets - and again, many thanks to Indian engg. schools with lots of interaction with certain phoren schools. I suspect that there was a lot of interaction with the Soviet rocket business (there used to be a Katyusha parked behind a blue curtain in one of those Top Secret places). But solid fuel ramjets came from Yoo-Ess-educated people. Liquids I don't know, apparently the first liquid-fuelled rocket engine in India was developed by a (then) young Air Force Lt/Captain mostly on his own initiative, while stationed at Bhuj. Later a very close associate of AK, enough said. This is what I mean - the breakthroughs come not by Official BrainStorming Chai-Biscoot with Traffic Light Methodology, but because one or two people simply go out there and do it.

So for the LCA: perhaps a good, harmless sequence?
1) University design competitions/ tech papers on modifying the LCA to all sorts of things? Must include more than cool CATIA - must include credible aero/ structures/ aerothermo and some knowledge of flight controls.
2) High school versions of such competitions to look at truly outrageous versions.
These two will amaze you, and shame the 'professional organizations' into hara kiri or jolt them into had work.
3) The above-mentioned Centers that start at least on 20 different projects, and have tough expectations of progress and deliverables. Let's revisit after we see some of these in progress.

Hey, maybe a BRF competition on LCA Advanced Design? With teams mentored by a panel? You may be surprised at how many reviewers you can get...

For example, see the US National Space Society competition on Human Settlement Design. Mostly nonsense, but fabulous efforts. Lots of Indian teams. I mean the ones that travel to the uber-expensive NSS Conference year after year (no travel funds from Ulan Bator

)

They get mentored by some of the Very Top in India, among others. How do I know? Because I've been roped in to answer their questions on a short fuse. Indo-Mongolian Peace and CoOperation.

Well.. I don't know about Peace: they went all sullen when I told them that certain approaches had certain minor flaws, like a half dozen zeros missing. But that is what I mean by getting objective people involved, who will say what is true and not worry about the Consequences.

Karan M · Post by **Karan M** » 14 May 2015 17:49

I don't disagree with anything you say per se, and this is somewhat positive "It's actually much better in Indian establishments..." but all I can say is our system is simply not funded for this "To have any hope of going beyond the present, India needs 3 or 4 competing, well-funded, well-staffed, well-led propulsion R&D units.. Its simply not there in our babus brains or even DPSU management. R&D would say, saar first let them sanction current requirements for current gen engine only saar. A callow youth once did a back of the envelope calculation to show how much money would have been saved by properly funding and supporting the MMR program at HAL for instance. But the powers that be simply don't care. I do hope that things change. The point that you raise about competing establishments is the pedal to the metal, no way but up, dead serious stuff that super powers do when they take any topic (such as engine tech) seriously. In India, we spend all our time cursing the LCA for taking valuable money etc and what a waste it is, and then the same jarnails and air marshals will swagger around & say aha, lets import Rafale at tens of billions, it will solve all our problems, it comes with TOT onlee yaar..they will say this with a brazen face and get offended if somebody points out how ridiculous the charade has become of import, import, import when even nations which make these gold plated items are thinking twice of inducting them. And these same folks appear on TV etc and constantly bemoan how money is wasted when spent on R&D, locally.

Until and unless this import mania is addressed and money adequately put into critical national endeavours (and by all means restructure, reorganize, do whatever it takes to set the programs for success and not just provide blank cheques) - things won't change.

Its a mix of vested interests and many people on all sides have made moolah of keeping teh gravy train running.

You are of course cent per cent correct about engines. Beyond the HF-24, if we even see the Su-27, the designer/s were informed that the Russian VVS specified avionics and stuff would mean a weight gain (CCCP electronics was behind in terms of compactness) and performance required was to be =/> than competing F-15. So the plane was made big/ger and the engine thrust upped correspondingly. When the design (like the LCA Mk1 hobbled by MiG-21 dimensions) didn't give optimal results, Simonov (the designer) said "fuggedaboutit lets redesign the whole thing". No mass media excoriation of Comrade Simonov and nor did his own AF scream and yell at him either. That sort of redesign from the clean sheet approach (to some extent) has been done for the NLCA Mk2, why not the LCA Mk3 then? Many reasons, but I'd wager one is IAF disinterest and hedging because theres always the next import around the corner, another because they simply want something today. And today India is buying Flankers and an Air Marshal goes to Russia and says "this is what Sukhoi guys tell me, that we are not ready yet to make fighters etc".

So yes, you are right & our system sucks. One only hopes that the economy improves to the point that the money wastage on subsidies (election victory etc) still allows for this sort of stuff. Otherwise we will keep importing weapons forever and exporting our brains as well.

shiv · Post by **shiv** » 14 May 2015 17:52

UlanBatori wrote: Hey, maybe a BRF competition on LCA Advanced Design? With teams mentored by a panel? You may be surprised at how many reviewers you can get...

For example, see the US National Space Society competition on Human Settlement Design. Mostly nonsense, but fabulous efforts. Lots of Indian teams. I mean the ones that travel to the uber-expensive NSS Conference year after year (no travel funds from Ulan Bator )

They get mentored by some of the Very Top in India, among others. How do I know? Because I've been roped in to answer their questions on a short fuse.

People other than newbie Mongolians have written gyan in the past similar to the stuff on this page. Back then I was pally pally with DRDO types who would only crinkle their noses at BRF until later they wanted to "collaborate".

I have cross posted a link to this page on the BR Facebook page FWIW. We need young people looking at such things. Tell me if I am mistaken but BR is doing pretty much zilch on facebook or Twitter

hnair · Post by **hnair** » 14 May 2015 18:00

For every interesting discussion thread in BRF, there **must** be a shadow discussion in FB and the posts tweeted out. Otherwise these thoughts reaching the teens are nil. Else tomorrow, they too will have to go on a painfully long journey of "discovery" on why India is facing challenges

BR FB page has a meagre 250 odd likes. Has to change

(Although FB would need a virtual maelstrom of bredators, doing deletes/blocks et al)

UlanBatori · Post by **UlanBatori** » 14 May 2015 18:32

Excellent posts from Maitya and Karan. This shows the very real difficulties. One parallel is the frustration in Yoo Ess circles about the (perceived) glacial pace of the Space Program. Instead of going on holiday to Mars and touring Jupiter by now (extrapolating from 1969) there is no human presence outside of the clunky ISS. Same with the Supersonic Transport. If you ask "HWHAI?" the answers are detailed and clear - and frustrating. I know someone who spent a whole summer at Dera Boeing Khan (on their $$) going around the company asking: Hwyphor joo canjelled the Ech Ess Cee Tee brohram in 1999, hain?

)
Answers were most illuminating: EVERY division said:

We were 400% ready and met all objectives, But did THEY do their jobs, hain?

This is the same as what has been happening in India for the past 40 years, except for the IGMDP, the GSLV and the Nukes and the LCA where there were "spires (Gopuras to be Indian PC) of excellence".

So NASA tried setting up the NASA Institute of Advanced Concepts.
"Don't let your preoccupation with reality inhibit your imagination!" etc. Deliberately set up to be "more than arm's length" from NASA, but where NASA input was provided as part of the review process. Projects had to be "more than 10 years away in feasibility, but below 30 years away". About 100 6-month Phase 1s were awarded, I think (10/yr for 10 yrs, maybe more). One out of 4 got 24-month Phase IIs, which was good $$. A few got picked up by NASA as Phase 3 and beyond. One space mission has been launched using that, I think. But each project had to show WHY it was not possible today, what technical advances were needed, a roadmap to success, and why it could be all done well inside 30 years.

Fabulous program. The entire program was "paper-free" - everything was done electronically. But the Reviewers were simply the best in the nation - mostly Apollo veterans, now retired. There was no great reward except a prestigious Beer Mug inscribed NIAC which proclaimed one to be an NIAC Fellow, one step from 400% Loonie. But oh the projects! For instance I saw one conference where they had a report by the guy(s) doing Quantum Teleportation. Another doing Caving - her speciality was going into caves! The project was to create habitats by inflating a balloon inside a lava tube on another planet, thereby getting a nice smooth-walled pressurized, radiation-shielded environment. Did these result in anything? The Quantum Teleportation thing turned into a super-duper cyber security thing with an unbeatable coding key.

But inside 10 years, the yada-yada-yada caught up ("Whyphor eej this $$ peeing wasted on fancy notions, hain, why not MY coujin's broject phunded, all corrupshun onlee"), and the money was sucked out to "address the Cost Growth of the Constellation Program" in 2006. And then the Constellation Program was killed. Then NASA 're-invented' NIAC, but this time as just a pet piggybank for NASA managers. With 3-month Tactical vision, not 30-year or 50-year Strategic. This is how Entropy increases, it is a fact of life. (not that the Tactical ones were not needed, but it killed 100% of strategic concept development to feed 0.1% of the tactical project needs. Everyone celebrated the great projects that came out - if they could figure out what they were.)

Getting back to LCA and the whole Indian combat airplane establishment, there are two important approaches, IMO:

1. Tactical: A set of small competitions/ projects to make progress on the micro-problems. I wouldn't be able to get the gyan on the stuff like Maitya posted, except by reading PeeAref (which might explain why I infest here now..) Neither can most mortals. Because these problems are only known to a few over-worked insiders. So why not find ways to farm these out and get them solved by people who have no idea what they are for? You may be stopped today from doing something because you don't have a simulation of how it will perform over a range of conditions, and you have no time to develop that simulation, not that it's hard. Why not farm it out to someone (takes a bit of pre-planning) and let them do it? Even Cloud-source it? If security is an issue, well, farm out 10 things, out of which you are only interested in one.

2. Strategic: You need a host of people outside (meaning in yak fields etc) looking at a host of outrageous things, which you can never present to Managers as your Risk Mitigation Waterfall. Let the kids look at them. A silica aerogel turbine disc and blades? Ceramic spheres (generated free in coal-burning plants) to make turbine blades? Supersonic compressor stages? Amphibious version of the LCA, rated to 100 m depth? Whatever else. Who knows? you may be amazed to find the options that are generated because people didn't know what they could NOT do.

If you search the web you will find a competition where the winning entry was a counter-rotating turbomachine design by a team of IIT Mumbai undergrads. Done in CATIA. Cool work! But someone needs to pick that up, not lose their gyan, and combine it with thermo/ structures projects by other teams.

Both of these need the Centers that I mentioned.

ramana · Post by **ramana** » 14 May 2015 18:57

UB my very thoughts too on BRF contributions to aero design genre....

http://forums.bharat-rakshak.com/viewto ... 8#p1837078

ramana wrote:Vivek and Indranil,

Could you be guides/mentors for BRF A/C design projects?

I am thinking of something small like a single seater powered by a small engine and walk the folks through what it takes to do a design.
Another is a small battery powered drone which can be made.

all the way from requirements to finished drawings!!!

Note the date....

I'll ask again: How many of those super-duper Kaveri Engineers that you know, can do a 1-D thermodynamic and gas dynamic flowpath analysis of the Kaveri Engine, let alone any other engine? With a calculator? What do they mean by "3 percent variation"? Thrust fluctuation due to compressor or combustor instability? (that would shake the plane to pieces). Polytropic efficiency? Sea level static thrust? TSFC? Mean time between failures? or 10-minutes continuous operation at max thrust with afterburner without flameout at the specified LCA ceiling, or blowing up?

The GTRE folks can do all that.
Some e-patra from a guru suggested compressor instability.
Need to check over weekend the e-patra folders.

narmad · Post by **narmad** » 14 May 2015 19:06

UlanBatori wrote:Excellent posts from Maitya and Karan. This shows the very real difficulties. One parallel is the frustration in Yoo Ess circles about the (perceived) glacial pace of the Space Program. Instead of going on holiday to Mars and touring Jupiter by now (extrapolating from 1969) there is no human presence outside of the clunky ISS. Same with the Supersonic Transport. If you ask "HWHAI?" the answers are detailed and clear - and frustrating. I know someone who spent a whole summer at Dera Boeing Khan (on their $$) going around the company asking: Hwyphor joo canjelled the Ech Ess Cee Tee brohram in 1999, hain? )
.....
Getting back to LCA and the whole Indian combat airplane establishment, there are two important approaches, IMO:

1. Tactical: A set of small competitions/ projects to make progress on the micro-problems. I wouldn't be able to get the gyan on the stuff like Maitya posted, except by reading PeeAref (which might explain why I infest here now..) Neither can most mortals. Because these problems are only known to a few over-worked insiders. So why not find ways to farm these out and get them solved by people who have no idea what they are for? You may be stopped today from doing something because you don't have a simulation of how it will perform over a range of conditions, and you have no time to develop that simulation, not that it's hard. Why not farm it out to someone (takes a bit of pre-planning) and let them do it? Even Cloud-source it? If security is an issue, well, farm out 10 things, out of which you are only interested in one.

2. Strategic: You need a host of people outside (meaning in yak fields etc) looking at a host of outrageous things, which you can never present to Managers as your Risk Mitigation Waterfall. Let the kids look at them. A silica aerogel turbine disc and blades? Ceramic spheres (generated free in coal-burning plants) to make turbine blades? Supersonic compressor stages? Amphibious version of the LCA, rated to 100 m depth? Whatever else. Who knows? you may be amazed to find the options that are generated because people didn't know what they could NOT do.

If you search the web you will find a competition where the winning entry was a counter-rotating turbomachine design by a team of IIT Mumbai undergrads. Done in CATIA. Cool work! But someone needs to pick that up, not lose their gyan, and combine it with thermo/ structures projects by other teams.

Both of these need the Centers that I mentioned.

+100
Can i post this on google+ FB ?

UlanBatori · Post by **UlanBatori** » 14 May 2015 19:07

Oh sure!!! With best compliments from Ulan Bator News and Conspiracies too !

UlanBatori · Post by **UlanBatori** » 14 May 2015 19:16

Ramana: The concerns that we have always had are :
1) Avoid teaching the wrong kinds
2) Avoid attracting wrong kinds of attention.

As my nephew (Mentor in how to get a Learner's License) remarked after I managed to wangle an Indian DL without any Driving Test (totally 400% halal - just required careful reading of the Rules and Regulations):

This is the Teacher's Worst Nightmare!

So I would suggest that it can be run by PeeAref, but only some links to the program/competition should be posted here, not the detailed gyan. Yes, we can get ***VERY*** realistic. Should be all 'pull', very little 'push' - demand that ppl come up with their own concepts/ models. This is one reason why I keep asking whether ppl know how to do a 1-D analysis: with info posted here over the years, one can get a very detailed picture indeed about Ell See Ya and Kaveri, as you know from the POK-2 days. More to the point; our leap-frog guesses of the uber-complicated things such as Polytropic Efficiency (as a random example) are likely to be dead-on, to the point where people might think we stole them. IOW, our eventual answers will be quite realistic, without having to go through tremendous detail. Wouldn't want to post those anywhere. The fB connection is promising. Serious yaks can be provided serious help without stepping outside any Lakshman Rekhas, the trick is that they must do the finding, not we.

Kanson · Post by **Kanson** » 14 May 2015 19:26

2. Strategic: You need a host of people outside (meaning in yak fields etc) looking at a host of outrageous things, which you can never present to Managers as your Risk Mitigation Waterfall. Let the kids look at them. A silica aerogel turbine disc and blades? Ceramic spheres (generated free in coal-burning plants) to make turbine blades? Supersonic compressor stages? Amphibious version of the LCA, rated to 100 m depth? Whatever else. Who knows? you may be amazed to find the options that are generated because people didn't know what they could NOT do.

Ceramic blisk made of alumina was available in 90s in one of the Bengaluru institute. Remember that was in mid '90. Poor guys perfected that using simple casting w/o any latest hi-fi molding tech.
Just to say such environment exist to an extent. All that needed is national will.

Cosmo_R · Post by **Cosmo_R** » 14 May 2015 20:06

Who knows? you may be amazed to find the options that are generated because people didn't know what they could NOT do. ^^^

+1

Apocryphal or not, Igor Sikorsky (the helicopter guy) is supposed to have said (in response to criticisms of his first prototype) :

"According to the laws of aerodynamics, the bumblebee can’t fly either, but the bumblebee doesn’t know anything about the laws of aerodynamics, so it goes ahead and flies anyway."

Doing it the same way every time is likely to get you the same result. Intractable problems require clean sheet thinking.

Jagan · Post by **Jagan** » 14 May 2015 20:15

UlanBatori wrote:
The HF-24 Supersonic Fighter then went to 2 huge, slow British-supplied, License-manufactured centrifugal-turbomachine engines

To allow it to take off, they used RATO (Rocket Assisted Take Off).

Even then, on the first takeoff run, the plane refused to climb. The brave test pilot, heroically trying to save the money poured in by the starving Indian taxpayer of the 1960s (India was a famine nation then) refused to eject, but tried his best to lift it. Hit a sand dune off the end of the runway, crashed and died.

IIRC, in the 1971 war this super-supersonic fighter was used exclusively as a bomber, escorted by Gnats and MiGs for protection. Even then, several were shot down.

I am sorry none of the above four points are true.

Rakesh · Post by **Rakesh** » 14 May 2015 20:24

Jagan wrote:I am sorry none of the above four points are true.

Direct and to the point

UlanBatori · Post by **UlanBatori** » 14 May 2015 21:01

I bow to your knowledge, I have no personal knowledge of any of those. Sources for all 4 points were the Design/propulsion profs at IITM in the 1970s, who had come there after / during stints at HAL developing the HF-24. The crash in question and the pilot's death was something that weighed very much on old Prof. B****l's mind - he used to talk about it numerous times (often mumble to himself even) during Aircraft Design classes as ppl sat around getting confused about other things. No mistake about what I remember hearing. He may have mixed up circumstances - or others may have got them wrong.

Another IIT prof, also involved in the propulsion side, was the main source for HF-24 stories about the propulsion system, including the one where they imported some engine (the RD-9F, probably) but discovered that the mounting points and connections were on the top on the airframe design vs. on the bottom for the engine, or vice versa. And they could not overcome that problem. This was mixed with the "we didn't have tools to deal with the engine" story. The RATO story was also one of those that came from this prof, so either he got it from Prof. B****, or both got it from the incident, I don't know.

According to both of them, the pilot just tried to salvage the plane, he was the best of the lot and he would not give up easily, and that was why he did not eject, or ejected far too late. The prof's suffering was very evident to all of us. The way it was related was like he was standing watching the takeoff, praying that the pilot would eject. THAT was the mumbling part of the story "WHY DIDN'T HE EJECT???"

Since I was an undergrad who had never heard of RATO or ejection seats until they told me, there can be no mistake about what I heard there.

The canopy incidents (there were TWO that they mentioned) was/were separated from the RATO incident in their stories. They did not associate those with any pilot error - they said that the canopy came unlatched in high speed flight, not at takeoff - may have been due to vibration.

But your source, the military officer listed on the BRF main page, apparently speaks from direct knowledge and memory about colleagues (though with a caveat that he may have also heard from others), so I bow to that. More direct than coming from senior engineers inside the program relaying their memories to undergrads decades ago after they left HAL, as lessons to avoid. Note that the BRF source says that the canopy problem (blamed on the pilot) occurred at the same time as an engine failure during takeoff. Did the canopy problem become evident only after he had gone beyond the point of no return? And THEN the engine failed?

However I do have a technical question for you guys: Given that multi-engined aircraft are invariably designed with a "one engine failure at rotation point on takeoff" as a required design condition, one has to wonder why even with drag from an open canopy (not enough force to tear off the canopy) the aircraft could not climb if there was only one engine failed. Ejection should not have been necessary, the engine would operate long enough to permit climbing high enough to return to base. IOW the thrust must have been pretty low from the other as well, hain?

Did they really flight-test a fighter plane that did not have enough thrust installed to take off, if one engine failed? You know that thrust needed for takeoff is like 0.1 of gross weight, hey? So I assumed that this test was one where they were trying takeoff with absolute maximum full stores load. Crazy times, to have tried that where there was not twice the runway length left ahead.

One of the profs mentioned is no more (he was already long retired from industry when he came to IIT), and the other is long retired and in not so good health, so sorry no chance of jogging their memory. Maybe my classmates might remember, but they were as 404 as I was.

Indranil · Post by **Indranil** » 14 May 2015 22:23

Vina, prime yak herder,

I have no problems with your discussions. I want them to stay here. Though they are not directly related to LCA, they are important. You both have the right to continue in pingrezi. Other posters who joined later, will be taught some history perioiducally to understand why. But, I request you both to slowly return to LCA discussions on this thread. There is a engine-only thread, where pure gyan can go to. It can be pingrezi there as well. But, if they are ramblings, I suggest, a new discussion thread be created under the name of "Alternative aero-engines for Indian needs".

ramana · Post by **ramana** » 14 May 2015 22:35

indranil, Thanks.

UB on HF-24, take a look here:

http://forums.bharat-rakshak.com/viewto ... 3#p1806463

ramana wrote:
vsunder wrote:Kurt Tank and the HF-24:

Kurt Tank and the HF-24
Aircraft engines were constant weakness that did the planes HF-24 and even LCA.

And even more interesting is the constant search for engines from cheaters.

We need to compile all stories to get to the truth.

negi · Post by **negi** » 14 May 2015 22:40

Couple of things GTRE is just like any other government institution holding it to higher standards than others is wishful thinking, secondly comparison with ISRO or IGMDP is also incorrect now I am not as technical as folks here but to keep things simple there is a reason why likes of China, NoKo, TSP and Iran have developed rockets and missiles but none of them have tasted similar success with a modern jet engine which is powering a fighter AC in active service . Same with nukes too.

UlanBatori · Post by **UlanBatori** » 15 May 2015 01:52

Yes, thanks, Jagan, Ramana, Indranil. Hard to track down the truth, I commend the patience of folks who try to do that. Everyone seems to have a different memory, thrown in organizational hangups, security hangups, misinformation, and jumbled memories and it becomes just impossible. What I want to see (serious opportunity coming up) is whether some good can be done to prevent history repeating. LCA has at least gone through that breath-holding period of flight testing, and is entering service. Maybe there is a good reason (c HF-24) why the Powers-That-B are OK with having a tested, phoren-guaranteed injin to power it until it is good and settled with the IAF. The noise about performance is pindrop silence compared to what would have happened if there had been an engine failure (of a desi-ind-genius injin) during flight tests!
But it is time to look beyond. So pls some indulgence for engine discussions here as directly relevant to the LCA. The key term these days is "engine-airframe integration".

What we see from discussion above is that there are two interests:
a) Improve an engine that fits in present airframe
b) Deal with re-engine with an F-414.

I had not realized what Adm. Nadkarni may have been hinting with the "can't provide for a bigger, better engine" in his 2001 article. May have been referring to the F-414. Amazing find: On the F-414 Wikipedia page, guess what's listed as "comparable engine".

Shows that the sales pitch is in full-press mode.

So is the F-414 bigger? Per GE data sheets, both the 404 for the LCA, and the Enhanced version 414, are 35 inch max diameter, and length is 154 inches! The 414 generates around 58 vs. the 404's 45 kN dry and has T/W of 9 (probably in afterburning) vs. 7.8 for the 404. I must be missing something. Inlet diameter is 31 inch vs. 28 for the 404, but is that a big deal in redesign? Probably that means much better bypass ratio for the 414. What is the hangup in upgrading to F-414?

UlanBatori · Post by **UlanBatori** » 15 May 2015 02:06

I wonder how tough it is these days to develop a pilotless version of LCA, just for routine flight testing purposes with 1 trial engine. I mean, the thing already controls itself with its augmented stability etc., hain? Operate from the Andamans or Lakshadweep or some other coastal place to avoid hitting anything if it falls. And re: the institutional resistances etc. - that is where the new window of opportunity may exist. Per some reports that I hear, The Top may intervene directly and instill completely new culture. What we want to do is ensure that there is good technical sense that goes along with the baniadom there. Quote from DeeArrDeeOh / EchAyEll:

Haven't had a good night's rest since ..... But we are having a wonderful time, so many things to get done, all businesslike, tight schedules and ambitious demands.

Also from potential customers who visited their shows this December/January:

Very professional! They really know their stuff, and they really want to bring in the private sector, small companies, to get things done. They come ready to explain exactly what they want! It's a new age in Indian defense!

Karan M · Post by **Karan M** » 15 May 2015 02:30

So is the F-414 bigger? Per GE data sheets, both the 404 for the LCA, and the Enhanced version 414, are 35 inch max diameter, and length is 154 inches! The 414 generates around 58 vs. the 404's 45 kN dry and has T/W of 9 (probably in afterburning) vs. 7.8 for the 404. I must be missing something. Inlet diameter is 31 inch vs. 28 for the 404, but is that a big deal in redesign? Probably that means much better bypass ratio for the 414. What is the hangup in upgrading to F-414?

We are moving to 414. In fact the most powerful variant of the 414 per GE (414 INS6) for both LCA Mk2 and NLCA Mk2. I think it was the higher thrust (apart from politics) that clinched the deal for GE vs EJ in the competition.

Karan M · Post by **Karan M** » 15 May 2015 02:34

negi wrote:Couple of things GTRE is just like any other government institution holding it to higher standards than others is wishful thinking, secondly comparison with ISRO or IGMDP is also incorrect now I am not as technical as folks here but to keep things simple there is a reason why likes of China, NoKo, TSP and Iran have developed rockets and missiles but none of them have tasted similar success with a modern jet engine which is powering a fighter AC in active service . Same with nukes too.

Its not like just another govt institution. There are Govt institutions and then there are Govt institutions. It has had significant hangups in getting to the level of the labs involved in other successful programs like IGMP, other big ticket successes etc. A big reason for that is the kind of leadership it has(nt) had. To be fair, it has had the hardest task as well, but loads of insider stories about how dysfunctional the setup was.

Jagan · Post by **Jagan** » 15 May 2015 03:04

UB,

Sources for all 4 points were the Design/propulsion profs at IITM in the 1970s, who had come there after / during stints at HAL developing the HF-24. The crash in question and the pilot's death was something that weighed very much on old Prof. B****l's mind - he used to talk about it numerous times (often mumble to himself even) during Aircraft Design classes as ppl sat around getting confused about other things. No mistake about what I remember hearing. He may have mixed up circumstances - or others may have got them wrong.

Its good to post sources - and I am glad you share the sources. One thing i learnt about history is that any story told via word-of-mouth needs to be checked against facts on the ground. I can state with the benefit of hindsight and the knowledge we acquired in the intervening decades that the professor from IITM was wrong. lets look at the four claims:

The HF-24 Supersonic Fighter then went to 2 huge, slow British-supplied, License-manufactured centrifugal-turbomachine engines,

The last centrifugal jet engine aircraft the IAF operated was the Dassault Mystere. All others including the orpheus, are axial flown engines.

Mach 2 fuselage was able to go up all the way to Mach 0.6 in a shallow dive. To allow it to take off, they used RATO (Rocket Assisted Take Off).

0.6 mach is 440mph at 10K feet. Even the WWII era Prop driven Hawker Tempest could do 500mph in level flight. The Marut was a speedy beast. It could easily overhaul the Hunter in level flight - and they could do more than Refer to the Marut book produced by Pushpindar Singh . I have never heard of the Marut using RATO. though it may have been used for a test flight or two, never on regular operations.

Even then, on the first takeoff run, the plane refused to climb. The brave test pilot, heroically trying to save the money poured in by the starving Indian taxpayer of the 1960s (India was a famine nation then) refused to eject, but tried his best to lift it. Hit a sand dune off the end of the runway, crashed and died.

We are talking about Gp Capt Das - his accident details are given here.

1. 10th January 1970 - HF-24 Mk 1R (HAL) flown by Gp Capt Suranjan Das (HAL).
Prototype aircraft canopy open; right engine failure suspected.

Groupie Suranjan Das' crash was perhaps partially pilot error. He was the greatest supporter of the HF-24 Mk IR with reheated Orpheus engines. It had the prospect of being earlier and better than the Jaguar. Its performance was less than it would have been if the rear fuselage had not simply been enlarged by HAL to house the larger engines and their nozzles. The nice area rule of the original design had been vitiated badly. All the same, the performance of the aircraft was impressive. All it needed was to get the right avionics. According to me, the other design work should have been for the addition of a second hydraulic system, and of course streamlining the fuselage a lot better than the fat end.

While taxiing out to the take-off, Groupie Das used to keep the clam shell canopy unlocked and hold it up slightly to get some fresh air. There was no retaining lever. It seems that on the fateful day, he forgot to lock it prior to beginning the take-off run. The canopy opened during the ground roll. The hinges were too strong for it to fly off. Ejection through the canopy, as in all Maruts, would almost certainly have led to killing the pilot. Hence, the canopy had to be jettisoned. Ejection, till the canopy was not in the way, was prevented by a locking pin. This pin was pulled out by a lanyard which would be extracted during jettisoning of the canopy.

For Groupie Das, with the canopy already open, its jettisoning was no longer possible. Ejection was also impossible as the seat was not armed till the pin was pulled out. The drag from the canopy was large and the aircraft did not get airborne. There was a debatable possible failure of the reheat of one engine. In short Groupie Das had no options left and died in the crash.

The author ofcourse was Gp Capt Kapil Bhargava, who commanded ASTE in 1971 under whom all the test pilots doing the Marut flying reported. He would have known what the CoI findings are and he was closer to the source than the prof from IITM. And ofcourse Groupie Das sadly was stuck in a position that did not give him any options other than to try and climb away.. the ejection seat did not arm, cannot fire, yet the canopy was such a drag that it bought down the speed... there was no question about him 'refusing to eject', he unfortunately could not do anything...

IIRC, in the 1971 war this super-supersonic fighter was used exclusively as a bomber, escorted by Gnats and MiGs for protection. Even then, several were shot down.

yeah I am probably in the nitpicking territory here

, but yes, the aircraft was used for ground attack - rockets and front guns. No bombs.. the bombers were ofcourse the Canberras, the Sukhois and MIGs when they were actually carrying bombs . Yes three or four were shot down. but thats not several, thats normal. Several would refer to the Sukhoi-7 of which 17 were lost, or even the MiG-21 of which eight were lost.

Do note that I am with you about the aircraft being underpowered and all that, just not with the other statements used to support this assertion. And I ofcourse have no say in the saga of the LCA - good or bad, but when history is thrown into the discussion and i see inaccurate statements made just because they are a good yarn, I have to step in.

Cosmo_R · Post by **Cosmo_R** » 15 May 2015 03:06

UlanBatori wrote:... What is the hangup in upgrading to F-414?

Is the longitudinal weight distribution the same for both?

Jagan · Post by **Jagan** » 15 May 2015 03:11

shiv wrote:I have cross posted a link to this page on the BR Facebook page FWIW. We need young people looking at such things. Tell me if I am mistaken but BR is doing pretty much zilch on facebook or Twitter

BR.com just started on Facebook.. BR-IAF is reasonably okay in size. BR on Twitter is doing okay as well.

hnair wrote:
BR FB page has a meagre 250 odd likes. )

250 likes because it started about 5 days back . Give it an year ..

hnair wrote:
Although FB would need a virtual maelstrom of bredators, doing deletes/blocks et al)

Certainly when we get into the 100000s likes territory we will need em ..

UlanBatori · Post by **UlanBatori** » 15 May 2015 03:59

Jagan, thanks for the correction! Of course I have no axe in this, just relating what I was told as wet-behind-the-ears undergrad eating up everything I was told, given who was saying it. The axial vs, radial was my error, confused what was being license-built at the Engine Factory in B'lore with what the Profs mentioned as low T/W engines, where they needed two instead of using one Russian engine. No other source available, of course the group commander is the one who would know why his pilot died, better than others, so thanks.

So I see that the HF-24 was only retired officially in 1990. The airframe was clearly designed to go transonic, given the fuselage shape (I'll ignore the Mach 2 for now). And I don't think the laws of pissicks or aerodynamics have changed a whole lot.

Is it so outlandish, given all the experience base that they must have, to put two F404s in it and turn it into a strike aircraft? Using it to test engines would be a bad idea because an uncontained blade failure on one engine would 'take out' both engines.

What would be missing? Advanced digital flight control system? The actuators were 1950s vintage, but they had manual backup which made it pretty rugged. The canopy, ejection seats etc have come a long way. Incidentally, back then, I don't think they had '0-0' seats, did they? I think those came later. Ejecting at low altitude going at 150 mph was probably death, except that you died by having your head bashed in or breaking your neck instead of burning to death. Even if the parachute opened there was little time for deceleration.

This is the sort of experimental project that we don't hear much of from the desh establishment. One could probably get to a much higher payload fraction/ range/altitude with these new engines. I am not saying to dust off the junked aircraft, but to dust off the technology and put in an assembly like for, say, 150 aircraft. Good use for F-404 engines as they are replaced with F414s. Given the lethality of the low-altitude strike environment, maybe make them the first unmanned low-altitude strike aircraft of the IAF?

BTW, the Egyptian NonAligned Engine is mentioned on one of the history pages - not from BR but may have been contributed by you.