LCA Tejas: News and Discussions

[Cosmo_R]

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.

"At a late stage India financed the Egyptian development of the Egyptian E-300 engine for use on the Indian fighter jet HF-24 Marut."

http://en.wikipedia.org/wiki/Helwan_HA-300

Turning to the Egyptians for an engine was a joke (on us).

Designing fuselages is glamorous. Engines less so. Lessons of HF-24:

1. Build the plane around the engine
2. We don't have the tech to build own F110-GE-132/F-135
3. Rather than just import, (100% FDI), ask GE/PW to make engines in India for LCA MK3/AMCA/HCA/Long range bomber with minimum order guarantee.
4. Nurture backward linkages to private companies for components and most important human know how.

JMT

[Vayutuvan]

Top Defense man (no not the scientists but the poltico) is an eye eye chai (tea) wala indjineer, after all.

At this point the real problem, I hear, is the number of engineering PhDs - its about 350 PA in India as opposed to 10K in China. Requires very little (relative to the big moolah being spent on ex) monies (AKA funds) to triple it in about five years which is the first step in a 10000 mile journey as our Asian brothers who illegally occupied north-of-Himalayas plateau would say. There seem to be a few proposals but no idea how things are going to pan out. I give it 1-1 odds. If it were to be Cong(I), I would have given 1-99.

[UlanBatori]

Yes, Cosmo, but there HAS to be a parallel Swadeshi Injun program, and just one Kaveri/Kabini is not enough. Making the engine does **NOT** equate to technology development, it is the opposite because they probably get ironclad legal documents saying that there will be no competitive development. Much more than "offset" programs, I would demand that there be no such deal - that co-manufacturing would be dictated by partnership as in selling to others. And I would bring undergrads through the factory every day and ask them to digest what they learn. This is what continues to amaze me: India had engine factories in the 1970s, making fine compressor and turbine blades and measuring them to fine precision. MiG engines have been produced for ages, so have the ones for the Su's. So WHY is Indian machine tool and engine-building capability not more advanced? This is where the lessons must be learned. Look at what the LCA has done: 15 years of flight test and prototype-building experience, flight control development, experience with all sorts of weather, altitude and runways. This is the pure treasure.

I remember asking someone at the B'lore Engine Factory (as a brat) why they couldn't copy those designs and make all-Indian engine designs. They were horrified, but explained patiently.

We are not ALLOWED to do that! We can only use these BLUEPRINTS and build EXACTLY as we are licensed to do!

This is the problem with License Production. You can still build HS-748s - except that now France is taking over from England, teamed with Tata to do the HS-748 replacement with L'Avion Nouveau avec les Propellers. I HOPE they don't do that with the LCA, 5 years from now!! "Dassault-Tata Tejasseau-Deux"

[Karan M]

"At a late stage India financed the Egyptian development of the Egyptian E-300 engine for use on the Indian fighter jet HF-24 Marut."

http://en.wikipedia.org/wiki/Helwan_HA-300

Turning to the Egyptians for an engine was a joke (on us).

Designing fuselages is glamorous. Engines less so. Lessons of HF-24:

1. Build the plane around the engine
2. We don't have the tech to build own F110-GE-132/F-135
3. Rather than just import, (100% FDI), ask GE/PW to make engines in India for LCA MK3/AMCA/HCA/Long range bomber with minimum order guarantee.
4. Nurture backward linkages to private companies for components and most important human know how.

JMT

That Egyptian engine was a German engine. Not a joke...see vsunders posts on that.

[Karan M]

Top Defense man (no not the scientists but the poltico) is an eye eye chai (tea) wala indjineer, after all.

At this point the real problem, I hear, is the number of engineering PhDs - its about 350 PA in India as opposed to 10K in China. Requires very little (relative to the big moolah being spent on ex) monies (AKA funds) to triple it in about five years which is the first step in a 10000 mile journey as our Asian brothers who illegally occupied north-of-Himalayas plateau would say. There seem to be a few proposals but no idea how things are going to pan out. I give it 1-1 odds. If it were to be Cong(I), I would have given 1-99.

But triple it in terms of quality not being lost I hope.

[Karan M]

I remember asking someone at the B'lore Engine Factory (as a brat) why they couldn't copy those designs and make all-Indian engine designs. They were horrified, but explained patiently.

We are not ALLOWED to do that! We can only use these BLUEPRINTS and build EXACTLY as we are licensed to do!

This is the problem with License Production. You can still build HS-748s - except that now France is taking over from England, teamed with Tata to do the HS-748 replacement with L'Avion Nouveau avec les Propellers. I HOPE they don't do that with the LCA, 5 years from now!! "Dassault-Tata Tejasseau-Deux"

Yes, we have not changed. Milan 2T and Konkurs production at BDL for instance (anti tank missiles) specify % of indigenization and over a decade and a half we have stolidly stuck to that (to what end nobody knows). Apparently we follow the letter of the agreement, so we can get more TOT next time around. Never mind following a different path and never needing TOT ever again!

[Karan M]

"At a late stage India financed the Egyptian development of the Egyptian E-300 engine for use on the Indian fighter jet HF-24 Marut."

http://en.wikipedia.org/wiki/Helwan_HA-300

Turning to the Egyptians for an engine was a joke (on us).

Designing fuselages is glamorous. Engines less so. Lessons of HF-24:

1. Build the plane around the engine
2. We don't have the tech to build own F110-GE-132/F-135
3. Rather than just import, (100% FDI), ask GE/PW to make engines in India for LCA MK3/AMCA/HCA/Long range bomber with minimum order guarantee.
4. Nurture backward linkages to private companies for components and most important human know how.

JMT

@ Rohitvats: You are new to the forum and may have missed an earlier discussion on the same topic. I have a coffee table book about the life of Kurt Tank written by someone very close to him a German. It is full of pictures. It has a very large section on Tank in Bangalore. The preceding section is on Tank in Argentina designing the Pulqui.
The book has many, many details and pictures of the Hf-24 in various stages of it's design. Some years ago before your joining date, I had scanned the entire Hf-24 chapter and gave it away to several people on the forum. Vivek Ahuja, Shiv, Ramana etc. easily come to mind.

The Russian engine was a dud. They were BSing Tank all along. The reason was they wanted the Hf-24 project to fail and so that India could be invested in the Mig. Of course one can say no that is not true etc, but I am only quoting a German who was in the design team with Tank and associated with him for a long time.
Brandner was the German who designed the Egyptian engine. The Egyptians had no expertise they just got Willi Messerschmitt and the Austrian Brandner.
Brandner came to India and demonstrated his engine. He was met by Air Marshal Ranjan Dutt at Mumbai and brought to Bangalore. Ranjan Dutt is the father-in-law of Anupam Kher and married to a Swiss woman. The book claims that Tank put his hand on the engine 10 mins after shut off and it was cool enough to touch such was the "excellent design characteristics of the Brandner engine". Tank was very impressed and wanted to go ahead but complications arose of a political nature.

The entire saga is there and also the innovations ( tricycle landing gear, area ruling it is all mentioned in the book, they were all innovations for that era and Tank introduced them) and very detailed specs of the Hf-24 and the story of the first flight when Roshan Suri got scared as the flight was at Rahu kala and according to the Germans did an abort and bashed up the plane and damaged it very severely. This was at Yellahanka. Suri's family had premonitions he would die and so had made a big ruckus. Tank usually piloted the first flight himself but HAL was scared and did not allow it. It was after the Roshan Suri debacle that Suranjan Das took over. The book states, Suranjan Das had a British wife ( this is true) and had no inclination to be superstitious. That is what the book states.
Tank also ALWAYS built a full scale model glider of the plane and flew it himsel to evaluate the low speed and handling characteristics. There is a lovely snap of the Hf-24 glider over the Bangalore skies with little pieces of wool to evaluate the flight characteristics. High speed wind tunnel tests were carried out in Switzerland by prof. Ghatage one of the earlier pioneers at HAL. There is a Ghatage hall or building or lectures something like that that HAL conducts. In all there were 12 German engineers who accompanied Tank to Bangalore.

[Vayutuvan]

1. Build the plane around the engine
...
4. Nurture backward linkages to private companies for components and most important human know how.
JMT

Let me address these two points on which I am not too qualified to comment but have an humble O.

1. Co-development can find a better operating point, especially when one can do enormous number of "what if" simulations in a reasonably short time and then winnow it down a few workable DFM combinations which also reduces the number of candidates. The number of comniations are still exponnetial. That is where well educated Mech/Aero/Controls (EE/Chem/Mech) PhDs have to come in to apply intuition and figure out the important parameters and winnow the candidates down to a handful (IOW 5 or 6) which have to reduce to 1-2 after lconsidering the state of the art, access to manifacturing technology and personnel. Then prototype, measurements, and ECRs to get the final release candidate. LCA is Neo - the One at this point. Use that and go forward.

...

4. Not to knock on our ye good old dEsh engineers and scientists and teachers - after all most of us were taught by those oldies when we were sponges to soaking up what ever they could dish out (good and bad) - manpower is a big problem.

FWIW

[Vayutuvan]

But triple it in terms of quality not being lost I hope.

That is the hope I did not get an answer when I interrogated (of course, gently, as that is my boss and one who taught me a lot of what I know today) about the number 350 and whether these are from places like IITs, BITS (which seems to be simply a shadow of its earlier self) and other highly regarded university campus colleges or it is everything - including your district HQ engineering college which granted PhDs to those who wrote cut-n-paste thesis.

The answer - it was in jest I am sure - I got was that if I felt so strongly about it why don't I zimbly relocate to dEsh I was somewhat "chankian" and said that moi not interested in administrative junk work. But then that person is muy guru (in every way) and he said - with some seriousness - that "one has to do what one has got to do. pick-and-choose is not allowed". Soon very soon (and hoping it is not too late).

[vina]

One thing i learnt about history is that any story told via word-of-mouth needs to be checked against facts on the ground

Oh, one important "facts" that used to be drilled into the brains of EVERY freshie taken around in group cycle tour of the campus during induction by see-nears used to be be this.

Stop in front of the Civil Engg dept, point to a huge water tank on a tall tower and ask the freshies. This water tank has never been used.Does anyone know why ? Pause dramatically and throw the answer.

The Civil Engg guys are such morons, they forgot to account for the weight of the water while designing the tank and it will collapse if filled. That is why! Har-de-harr... Yak..Yakk. Yakk. . The Civil engg freshies squirm and attempt becoming invisible!

[Cosmo_R]

That Egyptian engine was a German engine. Not a joke...see vsunders posts on that.

And what was the punchline?

[Karan M]

Fail to see your point, if there is any, that is. If we had funded that engine, the Marut may well have turned out differently. If there was a joke (on us), it was that we didn't follow through as versus "turning to the Egyptians".

PS: Every other country out there cooperates irrespective of politics, claims of superiority, inferiority etc. Classic case in point - see Israel & South Africa.

[ramana]

That Egyptian engine was a German engine. Not a joke...see vsunders posts on that.

And what was the punchline?

The Egyptians gave up on the engine and Brandner went home to Austria. Meantime India test pilot got to fly the Egyptian version of their plane and had many good things to say.

The worst part is the British offered to develop the better version of the jet engine for a few million pounds quite affordable if people had right priority.

One thing is HF-24 follow on (HF-74) never saw the light as by then the DPSA specs were drawn up to prefer the Jaguar of which famous Congressi family was the middleman agent.

[vina]

DPSA specs were drawn up to prefer the Jaguar of which famous Congressi family was the middleman agent

Jaguar was procured by the Morarji Desai Govt!

[Cosmo_R]

The Egyptians gave up on the engine and Brandner went home to Austria. Meantime India test pilot got to fly the Egyptian version of their plane and had many good things to say.

The worst part is the British offered to develop the better version of the jet engine for a few million pounds quite affordable if people had right priority.

One thing is HF-24 follow on (HF-74) never saw the light as by then the DPSA specs were drawn up to prefer the Jaguar of which famous Congressi family was the middleman agent.

Exactly. The Brits offered up the Orpheus. The hue and cry then (I remember this as news not Internet search) was that it was done to scuttle the Helwan and so the attention was shifted to the DPSA nonsense which btw, was the Blackburn Buccaneer. The Brits refused since it was 'nuke capable'. The IAF then went on this this treetop TSR2 like expedition and fixated on the Sepecat Jaguar DPSA (whatever that means).

The engine is something we ignore. From the P-38 Lightnings with their supercharged engines to the F-22s with their F119s and he F-135 engine for the JSF, this is what makes the plane.

From what I recall as news, the Helwan E300 was canceled by the Egyptians because it could not meet standards they set and they are not not known for high standards.

[ramana]

And don't forget the P-51 Mustang high performance was from the engine.

[UlanBatori]

So I think someone needs to explain this to NaMo in person. Only hope to bring about revolutionary change. Imagine where India would be if IG hadn't approved POK-1 and IGMDP and ABV hadn't approved POK-2. If NaMo says "go do it!" things can start singing. Seriously...

[vina]

The hue and cry then (I remember this as news not Internet search) was that it was done to scuttle the Helwan and so the attention was shifted to the DPSA nonsense which btw, was the Blackburn Buccaneer

. All you guys are so old, and such old timers who have seen it all and how for the period late early 70s to early 90s, the industry and the ecosystem was systematically destroyed by the import designs, and screw driver assemble (and hence "indigenous" ) business, financed by direct rupee trade with the USSR. There were good reasons to do what we did back then given the state of the economy, but neglecting domestic capability and R&D (which would have taken very little, like I once said to a poster Abhibushan here, like 10 airframes worth of fund in total over 10 years) was criminal .The disastrous economy in the seventies under Indira Gandhi and the lurch to hard socialism and everything possibly destroyed whatever was built area in terms of capability built in the 50s and 60s industry wide across industry by the mid 80s. I still remember talking to the Kaapee Board folks here in Bangalore and how powerful those babus were because they canalised bulk coffee exports to Soviet Union ,basically commodity exports with little value addition.

Compared to you guys, I am a baccha, in fact coming of age in during the Rajiv Gandhi era, when all the old folks I knew who worked in these places had either gone off into the blue yonder / retired and telling tales to the young kids of their days and when we were graduating the only thing left told to do was go abroad. It was a wasteland here.

I suspect I am younger than RBose though, who pretends to be a spring chicken .

[Singha]

>>1. Build the plane around the engine

it is claimed america follows the above idea. while europeans first design a plane and look around for a engine. hence american planes always tend to be large engined beasts dating back to ww2 design teams one can look at pix of P47 , P51, P38, hellcats, corsairs...other than the F14 tomcat I have never heard of any american mil plane being underpowered.

and that is why in later stages of the war, the P47 and P51 were able to outperform the german fighters at high altitude and using their long range able to escort allied bombers all the way to berlin and back.

[vina]

Bored at work, googled around and looked up Wikipedia entry for SU-7 after Jagan's post about SU-7 losses in 71 and I stumbled across something fascinating and that puts the lost decades between 1972 and 1990 or so in perspective.

We went and bought Jaguars, the Brits developed THEIR Fly By Wire on a Jaguar and proved it before putting it on other systems.
The Soviets did THIS

100LDU Control Configured Vehicle
A Su-7U modified with canards and a longitudinal stability augmentation system. It was designed as a testbed for a fly-by-wire system for the Sukhoi T-4. It was later used in 1973–1974 during the development of the Su-27's fly-by-wire system.

.

And 25 years later we go and BUY SU 30s!

WE were the folks who flew the largest number of sorties of the SU-7 in combat! WE are the largest users of the JAG and probably bought the most airframes and did DIDDLY SQUAT in terms of fundamental R&D with those platforms.

We were making the Gnat /HAL Ajeet (improved Gnat) until 1984 or so. IF only we had used ONE airframe, to do R&D with just a rudimentary stability augmentation system (not a full nine yards FBW) and put in a composite wing , we would have entered the LCA program with a far far stronger industrial base than we had and could have lopped off close to 10 years out of the program.

I think the basic resolve should be Never Again will we allow such a thing to happen.

[shiv]

A little fyi about the HF 24 Marut - from the Marut history book IIRC

[shiv]

Bored at work, googled around and looked up Wikipedia entry for SU-7 after Jagan's post about SU-7 losses in 71 and I stumbled across something fascinating and that puts the lost decades between 1972 and 1990 or so in perspective.

We went and bought Jaguars, the Brits developed THEIR Fly By Wire on a Jaguar and proved it before putting it on other systems.
The Soviets did THIS

100LDU Control Configured Vehicle
A Su-7U modified with canards and a longitudinal stability augmentation system. It was designed as a testbed for a fly-by-wire system for the Sukhoi T-4. It was later used in 1973–1974 during the development of the Su-27's fly-by-wire system.

.

And 25 years later we go and BUY SU 30s!

WE were the folks who flew the largest number of sorties of the SU-7 in combat! WE are the largest users of the JAG and probably bought the most airframes and did DIDDLY SQUAT in terms of fundamental R&D with those platforms.

We were making the Gnat /HAL Ajeet (improved Gnat) until 1984 or so. IF only we had used ONE airframe, to do R&D with just a rudimentary stability augmentation system (not a full nine yards FBW) and put in a composite wing , we would have entered the LCA program with a far far stronger industrial base than we had and could have lopped off close to 10 years out of the program.

I think the basic resolve should be Never Again will we allow such a thing to happen.

The IAF must get involved. The IAF needs to start at NDA level and teach courses on the need to get involved with industry,

[UlanBatori]

The reason I don't infest the Kaveri dhaga is because it is too traumatic. But I wanted to ask about this particularly traumatic aspect: Some time back I saw something where HAL/ADA/DRDO had gone to get CHINESE HELP (I mean PRC, not Formosa, though the underlying loyalties are the same in both) to improve LCA/Kaveli. Any updates on this? Much success with Photoshaap? Who the **** plomoted this, and Hu autholized it, pliss? Is it still undelway? Chinese help in writing LCA controls and weapon guidance software, for instance? I hear they are really good at math too.
Which is what reminded me of the Non-Aligned Injin 'Al Static Bin Cairo' March IV.
To do the things we suggest here, one needs a "SkunkWorks" / "PhantomWorks"/"Los Alamos"/"Sandia" type entities. I thought DRDO/BARC and ADA were those, until I saw the CHINESE being invited, and in fact on any given day at the cafeteria, one encounters many ppl from certain other countries that I won't mention here. All of which suggests that the hype/reality ratio (HRR in B*arSpeak ) ) is pretty high.

Again, the time is now to impress upon NaMO the need for such things, besides all the hype about welcoming FDI, Open Private Bijnej in Dephenj, etc. manages to sell everything good in India at cheap, cheap prices. To paraphrase my Fitting Shop Gulag buddy's immortal Pinakin Ke Dohe:

HAL ja baithe ped pe
apne *** latkaye
jisko jitna chahiye
kaat-kaat le jayiye

Advanced engines, advanced flight controls, stealth techniques and other things need to be done in entirely non-publicized places. I hope there are such places.

*And the reason I pooch these things and infest hiyar eej because there may be a window of opportunity

[Karan M]

Never heard of that. Are you sure it wasn't our beloved DDM

[UlanBatori]

Nope, can't find it on Googleswara. Man, my credibility is taking a beating, but I am sure of what I saw.

[geeth]

Is it possible to design/build FBW system / write control laws on an a/c bought from abroad? If so why ADA had to go to.amrrekha to test? Testing it on one of the IAF imported maal would have acheived the goal.

[ramana]

UB, PRC scientists publish in the DRDO Defence Science journal. Quite detailed stuff too!

CosmoR If you recall Blackburn Buccaneer was already long on the tooth by then and went kaput!!!


Vina, While Jaguar was finally ordered by Janata govt, recent revelations show that Rajiv Gandhi was a "agent'' for the transaction. Got first taste of cut in arms sales in that deal.


Any way back to topic.

Shiv, You are good at psychology.
Its the institutional culture.

Carl Builder, a RAND scholar wrote a book "Masks of War" where he analyzes US military institutional culture. uses British experience also. Hence by extrapolation can be stretched to India too.
In the book he finds air forces tend to love flying and want nothing to do with how it gets there. For instance way back he predicted USAF will be willing to give up the missile numbers to get more planes!*

Soon after the book changes came around where USAF understands its first job is to help win the wars.

* I find similar thing with lack of IAF strategic missiles deployment.
Maybe some command decision but never heard any debate or tussle about this.


From UB and Vinas' posts there is a need to develop a clean slate jet with world class specs no matter. Because such engines exists it can be done in India too.
Time, Money and people have to be assigned.

First remove engine development from GTRE-DRDO lab structure.
Create a ADA like vehicle (Jet Engine Development Center) that leverages DRDO lab infrastructure and make it permanent. Don't want situation of what next anxiety in the workforce.
GTRE can do basic research in flame CFD, high altitude chamber etc., etc. All this is still needed.
When you want engineering products cant have lab atmosphere.

[Philip]

It may look as if it was an easy dump of the HF-24,but at that time,when the Helwan engine was being developed,the Israelis sabotaged the Egyptian effort at developing their own indigenous fighter/engine(allegedly bumping off/scaring the key scientists,including Germans) which was then abandoned.
Which western nation offered us an alternative engine? It was Cold War time.We couldn't at the time proceed further. The Russians then stepped in with the MIG-21 offer,which we acquired in large number,building hundreds at home too, which in hindsight enabled us to maul Pak in '71 and develop the infrastructure of a fledgling aviation industry . At that time,the MIG-21 was the Soviet's best fighter aircraft.It has served the IAF for 50+ years and looks like it will still be flying in 2020 Bison avatar! Then came the HF-74(?),which was abandoned almost as soon as it was conceived. It is only in the last 10-15 years that we have been able to get Western mil tech relatively freely and at a price too!

Where we funked is in the aftermath of the Jaguar acquisition. We never bothered to develop it further,and acquired the M-2000 without TOT/local manufacture,had it been done so,it would've seen us build at least another 120 M-2000s at home,making the entire huge exercise of the MMRCA deal ,now scrapped in its original avatar, unnecessary. 30+ years on,we are only now (still) talking about a Jag upgrade,while a prototype still hasn't flown!

But it is true to state that the IAF's acquisition policy has been mainly that of a knee-jerk twitch and fumble every time Pak acquires a potent fighter from both West and East.We've waited for 2+ decades for the LCA to arrive in IAF colours ,still waiting for the bird to cross the combat capability "finishing line".

[ramana]

Philip. The British offered the next model Orpheus suitable for HF-24 to be developed for a paltry sum. Not agreed to by govt complex.:MoD, IAF & HAL.
The mentality was lets buy an already developed engine from somewhere.

Please look at the French mode of development of jet engines. Right from beginning they took the Nene and copied it, developed it and went on to power built Ourgan, Mystere, Super Mystere, Mirage, Rafale.

India gets to buy each of them except the Super Mystere!

And the French were the ones who put up the funds to develop the turboshaft engine for the helicopters which gave the heavy lift capability. Again a German idea taken by the French.

What prevented India from inviting Brandner and set up the engine factory in India?

Reminds me of Aesop's fables (grasshopper and ants) of relying on someone else to do the hardwork of engine development.

Repeatedly they were hoisted on the jet engine petard.

BNTW even piston engines are not there!!!

Lycoming engines are still license built.

They (aero community) begin development on hope that a foreign engine is available and when it comes to building the aircraft they find its unavailable, underpowered or piece of junk.*

HF-24, HJT und so weiter.

HAL engine division should have been spun off with GTRE as captive lab to it.
IAF has its own adhocism stymieing it.
In the end its the IAF that doesn't get the planes it needs for effectiveness.

----
Yiddish saying: Overfeed on hope, you will die of starvation.

[vina]

Is it possible to design/build FBW system / write control laws on an a/c bought from abroad?

If the Navy can build a new hull around steam turbines imported from abroad, what is going to stop you from writing computer code for flight controls for modifications of a fighter/trainer that you made for 20 odd years and in fact fixed all the bugs in the original and improved it like the Ajeet?

[vina]

The British offered the next model Orpheus suitable for HF-24 to be developed for a paltry sum

Rs 5 cr thereabouts is the amount thrown about if I recall from having seen it somowhere, which anyways wasnt a "paltry" sum for India back then. Today with the Rupee inflate to Rs 100 a pound it is trivial, but back in the days when people knew 1:1 rupee to pound parity , it was like Rs 500 crores

In fact, wasn't the first budget presented by Independent India something like Rs 350 crores or therabouts, and that was just 15 to 20 years earlier!

[geeth]

If the Navy can build a new hull around steam turbines imported from abroad, what is going to stop you from writing computer code for flight controls for modifications of a fighter/trainer that you made for 20 odd years and in fact fixed all the bugs in the original and improved it like the Ajeet?

If they do it, then the a/c also will be floating in the sea, unless the designer is willing to co-operate. In our case, neither the Russians nor the Brits would have done it looking at their past history.

I have heard from Army the the main engine crank shafts of the T 72 tank cannot be interchanged ...only Ruskies know what fits in which production series..I am just quoting some one..and have no proof. If true, that is the cooperation we can expect.

everything is written in nicely bound service books..follow it religiously ..or get in to trouble. Very less space to play around.

[ramana]

Most likely match machined crankshafts or series matched crankshafts.

[Gyan]

Hal has right to Tot of Shakti engine but they are doing Zero manufactering. Why?

[Singha]

because IAF is happy with imported engines and there is no domestic drive to make our own turboshaft.

[vina]

If they do it, then the a/c also will be floating in the sea, unless the designer is willing to co-operate. In our case, neither the Russians nor the Brits would have done it looking at their past history..

The HAL ajeet was a radically different plane from the Gnat. The ajeet had wing tanks and four pylons while the original had no wing tanks and two plyons. More weapons were integrated, all up weight increased, and undercarriage strengthened. The unrealiable hydraulics controls and electricals were fully reworked, better gun sights fitted. The works.

And in fact, HAL came up with an Ajeet trainer as well, which the Air Force which was hell bent on the Hawk refused to buy and would rather wait for another 20 years before having an AJT!

If so much was done in improving the fighter, why couldnt they put electronics into the controls and replace the metal wing with a composite as an R&D project. Very well capable of doing that.

[geeth]

How will you develop the codes without knowing the flight characteristics ? Who else other than the designer knows it and the design limits? Brits developed FBW in their OWN plane. So did Russians and all others including India. Even here Americans parted with the details of F 16 to Indians so that they could suitably write codes for testing it in F 16.

I dont know if anybody will take the risk of trying it on a plane without the assistance of the designer.

[ArmenT]

>>1. Build the plane around the engine

it is claimed america follows the above idea. while europeans first design a plane and look around for a engine. hence american planes always tend to be large engined beasts dating back to ww2 design teams one can look at pix of P47 , P51, P38, hellcats, corsairs...other than the F14 tomcat I have never heard of any american mil plane being underpowered.

and that is why in later stages of the war, the P47 and P51 were able to outperform the german fighters at high altitude and using their long range able to escort allied bombers all the way to berlin and back.

Actually, the P-51 was originally built with a weaker Allison engine. A few of them were given to the Brits who used them in a recon and fighter-bomber role and found them a bit underpowered, especially at higher altitudes. It was the British that replaced the Allison with the Rolls Royce Merlin engine and made it the high altitude performance fighter that it became. They also gave the engine tech back to the US and the Packard Motor Company built the Merlin engine under license.

On the other hand, the idea of "you just can't beat cubic-inches" is definitely an American trait and is not restricted to aircraft engines alone, but also shows up in automobiles. Now back to topic.

[Shalav]

^^^ Umm Flying characteristics gyan comes from

a. 10+ years of operations of the type
b. 10+ years of experience with complete overhaul of the type
c. ability to remove and study all components

Its not that big of a deal the Chinese do this regularly with Russian aircraft since the fifties - no?

[UlanBatori]

details of F 16

F16XL which is completely different beast, IMO
I think F16XL is mainly a development platform, where you can program the flight control system to behave like XXXX where XXXX is a variable foreign aircraft.

Answer to how do we do XXXXX is of course EZ to type from armchair, but these days it is a bit different from how it used to be. Point is that everyone knows in general how an aircraft works. A flight dynamics model can be developed with several programmable derivatives and other values. If you take a gizmo that flies, and simply record the control inputs, and airplane responses (output), you can do System Identification and get those derivatives, at least as pieces. No, things are not linear so this is painful, but it can be reverse-engineered.

This is why the Americans with the vijiting desi team could program the F16XL with actuators meant for the EllCeeYay, and make it behave like an LCA. Then after POK-2 they kicked out the desi team and held the actuators to ransom, so that there was a long delay while building the actuators again, AFAIK (all I know is what I read in the usual quarters, and the rest is my speculation).

So in principle at least, one can take an HF-24 or Ajeet, study its responses, rip out some of the rods and linkages one by one and replace them with wires and servo motors and maybe optic fibers, and tie them all into the control system. Run the simulation on MS Flight Simulator, then graduate to more sophisticated versions, get the pilot-in-the-loop simulations etc. Before there is a single test flight, thousands of hours of armchair flight experience can be accumulated. Then, as vina says, why not replace aluminum skin panels with composite ones, replace other non-critical parts, then graduate to tougher parts. New engine.

I just find it depressing that these things don't seem to be culturally ingrained. The Top in India seem to be mainly interested in getting baksheesh to buy ever newer shiny phoren, while ignoring all the opportunities to make revolutionary progress at the grassroots level.