LCA News and Discussions

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Indranil
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Re: LCA News and Discussions

Postby Indranil » 21 Oct 2010 04:14

Yes. But I am sure he is as much a well wisher of LCA as anybody else. It always helps to have a knowledgable critic.

I am sure he understands composites, stealth, radar and equipment in the modern "scenario". He never championed against them. He speaks of tradeoffs and a possible alternative to the present layout. Whatever he spoke was from basics of aerodynamics (even I could understand)!

He clearly names his article as an "open source" assessment, and he has done just that.

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Re: LCA News and Discussions

Postby NRao » 21 Oct 2010 04:22

A prof, I would think, would have better access than to envelopes, to make even simple computations. Hopefully he would be kind enough to qualify it "just for fun writing", or the like, along with his honest "open source". And, ........ perhaps publish the article in a regional news paper way down in Kerala or the like.

But ............................ such is life.

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Re: LCA News and Discussions

Postby Karan M » 21 Oct 2010 04:41

indranilroy wrote:Yes. But I am sure he is as much a well wisher of LCA as anybody else. It always helps to have a knowledgable critic.


Prodyut Das is no well wisher of the LCA. If he is, he sure disguises it well. And second, to be a knowledgeable critic, one should keeps one biases at the door.

I am sure he understands composites, stealth, radar and equipment in the modern "scenario". He never championed against them. He speaks of tradeoffs and a possible alternative to the present layout. Whatever he spoke was from basics of aerodynamics (even I could understand)!


Your quoting words in bold does not make it so. If he understands them, his articles clearly show no evidence of the same. Talking of merely aerodynamics and harping on that alone, and that too in a half baked manner, implying that aircraft which choose to gain weight via advanced avionics are all mistaken, while ignoring the huge advances that are taking place in weapons systems is bizarre and reeks of having a fetish.

His so called alternative to the present layout could have been presented in a factual objective manner without petty sarcasm and snide jabs at those making the aircraft as well. It should be clear that not only does the good professor have a bee up his bonnet about light aircraft, but he also has the superiority complex and holier than thou syndrome often sported by those whose crackpot ideas are not embraced by the larger community. The result, whimsical articles in the press and jabs at all and sundry.

A serious critic, and one who is well informed, does not need to resort to pettyfogging to get the point across.

He clearly names his article as an "open source" assessment, and he has done just that.


An open source assessment which dismisses the credible achievements in avionics, weapons platform technology, flight testing and even performance as "self praise" and mocks the development program. Such an "open source" assessment, would not pass the most basic of tests when it came to a serious proposal. And that is why such crackpot ideas about light fighters end up going nowhere. First, let this self proclaimed expert give credit where it is due, and honestly evaluate the huge holes in his "light aircraft" arguement against modern AD systems, whether they be air based or ground based.

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Re: LCA News and Discussions

Postby Karan M » 21 Oct 2010 04:47

Kartik wrote:While I have great respect for Prof. Prodyut Das' seeming knowledge of aircraft design, I cannot but be befuddled by his continued tirade against light fighters that have modern avionics systems. He seems to be the type who would blast Maruti Suzuki for introducing a Maruti 800 when the Ambassador would've done the job just fine with minor tweaks. Or he'd be blasting newer hatchbacks when the Maruti 800 would've done the job just fine with minor tweaks. The problem is that product design cannot just always be based on tweaks and tinkering of older and existing designs. At some stage a clean sheet design is required, and in fact even desirable especially as modern manufacturing, design and analysis methods become available.

Some parts of the article are good, but some are really just his personal opinion. I for one, thought that the ram air scoop added a bit of personality to the Tejas design. He calls it something that would offend a "wife-beating raddi-waala" which is nonsense to be honest. If it does the job it was intended to do then what the hell ? The Typhoon has a scoop like the Tejas, and the Gripen has one under its fuselage. These are functional, but Prodyut Das simply labels them as offending the general layperson's sensibilities (it’s a matter of personal opinion) while not pointing out any deficiencies by adding these.

And when I say functionality it is for a reason- for instance, I work on a derivative program where the ECS system has been modified due to higher flow requirements for a larger volume cabin. The earlier system (used for 3 decades and more) was elegant, with louvres and now it doesn't work- the reason being that now that CFD exists, the ECS engineers know how much flow they need and consequently need a larger duct to dump the hot exhaust gas. 2 decades ago, they possibly just guesstimated the exact volume that was required to be transferred through the ECS and the temperatures inside the duct. if it failed during service, the airline came back and changes were made.
Now- they need a new vent that in turn opens up a duct right into the air-stream and generates drag. What is the option to prevent that? Other than to re-design the entire ducting system (that can take 1.5-2 years), they could possibly switch off the air-conditioning and kill some passengers. Looks dirty yes, but it is functional. The earlier design would leave these hot exhaust marks on the underbelly and worse, panels would fly off the aircraft. Now we can study the effects of temperature better (thanks to powerful CFD tools) and we understand the issue better so in-service issues will be lesser but a slight performance penalty may be required.

So, without really being part of a program, an outsider like Prodyut Das can sit and be smart and say "they were foolish to do this and that and this". Which is basically an opinion which everyone has, but without the perspective that comes from knowing what options they had, it has no meaning.

Some aspects of his article are quite inaccurate-such as the empty weights of the Tejas and Gripen. LCA is now known to weigh 6500 kgs and weight reduction optimization is a part of the mandate for the Tejas Mk2. The Gripen A weighed 6500kgs and Gripen B was 7100 kgs. The Gripen C weighed 6800 kgs and all this is per Saab literature, not some Wikipedia data.

While it is true that the Gripen's landing was designed to a higher rate of descent than that of the Tejas, it is true that the Tejas' landing gear requirements were modified at design stage to be able to sustain 10.5 m/sec rate of descent at the time of impact with runway during landing. Maybe ADA should've asked Messier Dowty or Goodrich Landing Systems to design the gear for them since they have many decades of experience and are the default designers of landing gear for Boeing/Airbus/Embraer aircraft. Then there'd be no mistakes at all. That is the solution- keep designing, don't give up. Else basically just sub-contract everything to others who have been doing it for years because your first effort will have some mistakes and you have patrons who cannot bear any mistakes.

Has the Tejas suffered a landing gear collapse as yet? nope. Will it in service? Don’t know but seems highly unlikely. But other aircraft have, most notoriously the F-16, whose spindly nose gear has on multiple occasions broken while landing and taxiing. Would that be considered ok? A lighter landing gear that might suffer a failure during service? Or take the JF-17's landing gear whose single nose wheel (with half-fork) design is similar to that of the F-16 - any issues reported ? No- but it didn't even feature a steering system initially (it was added later) and when a video of it was shown where the camera was mounted near the nose gear, the shimmy in the nose gear was there for all to see. Just in case others don't know what shimmy means, it is not desirable in a landing gear. Not the best possible design but as as long as it is not a catastrophically bad design, it shouldn't be a big issue.

Regarding the design of structures to fail at just 100% of the ultimate load and not 101% of the ultimate load, well it is easier said than done. We know what happened to the Airbus A380's wing that failed just below 100% of ultimate load. The best brains money can buy in Europe were behind that wing's design and analysis and it still happened. It set the program back and cost money to fix.

And it is not so easy to do either. Preliminary loads are obtained by a mix of wind tunnel models, experience (from an existing similar design) and are not always the most accurate. In all aircraft design programs, some risk is associated with preliminary loads and flight testing is required to confirm these loads. Some regions like the fairings are not modelled in a detailed fashion on wind tunnel models and so you get fuzzy results there. How confident you are about your preliminary loads can in some ways influence your design and analysis- if you design it to 100% load and the load goes up by 1%, you are hosed. You need to re-design, re-analyse and re-release drawings to manufacturers. All of that costs money and time.

As I said earlier- its easier for an academician like Prof Prodyut Das to sit by the side and criticize (after all hind-sight is 20-20), but very rarely is a first effort product in a new domain a total success. If you make the same mistake again and again then it’s a different matter (and even that is not new in the Aircraft business, since program timescales are such- one person working on one program may not work on the other and may not get to implement lessons he learnt in the first). How energetically you support it and put in efforts to overcome the issues are what will be critical.


Well said. There are dime a dozen, self proclaimed experts on the LCA and all sorts of programs in India, who have all the time in the world to sit around and gas away, as if it was the reawakening of the great Indian coffee house. Meanwhile, the world marches on, while Shri Das's aesthetic sensibilities are offended by ram air scoops, he thinks the MiG-21 had an AI radar because the Russians fell into a me too fetish (and India even used these primitive sets for Early Warning in 1971). The likes of Shri Das are ever too keen to sit in their ivory towers and pass comments, but it never strikes them, even once, that their ideas may have flaws in them.

The IAF would have laughed HAL etc out of the park, if they went ahead with what Shri Das suggests of developing primitive simple fighters against advanced opponents, and well they would. With the amount of investment to train a fully ops combat pilot, apart from the human and morale factor, they cannot afford whimsy when sending them to war.

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Re: LCA News and Discussions

Postby hnair » 21 Oct 2010 05:28

NRao wrote:And, ........ perhaps publish the article in a regional news paper way down in Kerala or the like.


WTF? "way down"? What did we do to deserve this, other than tinker up a PSLV that is already :oops: in service or a 200KN cryo-baby engine? My H&D is "way down" :((

IMO, Prof Das' article seem more like a few personal thoughts he penned down than a critique of LCA, so I guess we can just read it up and move on. btw, on wish lists, LCA Mk2 should have those cool trapezoid intakes. Since Super Horny has it, must be good stuff. And a gimballed khulhar holder by the window rated to 9G turns 8)

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Re: LCA News and Discussions

Postby Rahul M » 21 Oct 2010 05:36

to repost my (rather facile) comments to another article of his from an earlier page in this thread

precisely, I'm sorry but the mass attack scenario is no longer that appealing. below a certain tech level, swarm attack would have all the effectiveness of a swarm of flies hit by bug spray, we saw that very well when israel went against syria in 1982 and again during GW.

there is a minimum tech level that is necessary and IMO the LCA constitutes the lower end, in a good way, since it is affordable. it is by no means certain that a good aeronautical engineer is a good military theorist as well.

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Re: LCA News and Discussions

Postby Kartik » 21 Oct 2010 06:36

Just look at the JF-17 ok ? Airframe designed by the Chinese who have for decades tinkered around with Soviet designs to come up with their own. And they've used only aluminium alloys in their entire aircraft with titanium alloys where required due to high temperatures or strength requirements. And they have an empty weight of 6500 kgs even though it was designed to +8.5/-3.0G design factors. Any structural engineer will know what that means- that if it was designed to 9G/-3.5Gs then the forces acting on the airframe would be higher and consequently the weight would've been still higher. Yet, do we see any Chinese or Pakistani saying that the JF-17 is a failure because the weight is 6500 kgs empty?

Prodyut Das' attitude is so negative and so warped in time, its crazy. I mean suggesting that we come up with a Gnat II as a design project with Tata, L&T or Godrej ? Just how ridiculous is this ? Does he seriously expect that the IAF will even bother to look at a 1960s vintage design in a new avatar just because it was originally a successful design back then? Did this guy even look at the Gnat's attrition rate ? It is in some respects an utterly ridiculous article.

I can only hope that people like Air Comdr Parvez Khokhar or someone like him who has in-depth knowledge of the LCA program based on his being the Project Director (Flight Test) come up with an in-depth article that tackles the type of accusations and points Prodyut Das has raised. And also point out what the issues are and maybe give some suggestions as to how they can be dealt with.

BTW, the LCA's basic design was done in COLLABORATION with Dassault. After all, it only emerged after the PDP phase where Dassault was integrally involved, even allowing company test data to be used for the LCA's configuration studies. So, its not like someone in ADA/HAL/NAL just decided that we'll go with a delta wing design because its the new look of the 1980s.

The gratuitous remarks made in the article are totally uncalled for and as Karan put it, show a holier than thou attitude. In most respects, he is basically saying that the entire LCA program is a waste which is bullshit to be polite.

I can't help but laugh thinking that if he had his way, the IAF would've been flying hundreds of Gnat IIs with dial instruments, no radar and no avionics worth talking about. Inclement weather? The fleet would be grounded then. But Mr Prodyut Das could then sit and find faults with that approach too I guess.

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Re: LCA News and Discussions

Postby Vivek K » 21 Oct 2010 06:48

Agree with Kartik. The guy is looking for fame and mostly Indians like to bash Indians. Read it, use for washing your a$$ and flush it down the toilet.

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Re: LCA News and Discussions

Postby SaiK » 21 Oct 2010 06:48

I am yet to see diagrams/pics about LCA - inverted Y duct or S duct for the advanced MCA. Things are still kept secrete about PAK-FA ducts. The engines has partial horizontal view exposure to radar thus not that LO!.
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Re: LCA News and Discussions

Postby shiv » 21 Oct 2010 06:48

Prodyut Das is a lateral thinker. He does provide some great insights and alternative viewpoints - but his ire seems to be directed at fossilized thinking and his attitude can be summed up by "Better to have working third generation in large numbers than attempting fifth gen and not getting there at all. He justifies this by saying that all the 100 or 200 to 1 kill ratios that are advertised break down when you have 4:1 or 6:1 advantage in numbers and quotes examples to boot.

Nobody can know the truth - but what Prodyut Das does is to ask if huge investments and long periods of time chasing the unattainable cannot be replaced by doing what is achievable reliably today and asks why nobody among the defence research set up are even looking at that possibility.

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Re: LCA News and Discussions

Postby Singha » 21 Oct 2010 07:01

that approach could work in lower end bread n butter stuff like mortars, 105mm guns - who needs 20lb guided grenades costing $100K launched from VLO JSF?...5km shorter range than best-of-breed will suffice. but in fighters the bar to be remotely competitive and get back in one piece is high. gnat-MKI would get shot like flies.

we are talking of people's lives here. let him strap up in a gnat-MKI and go out to shoot a few bandars.

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Re: LCA News and Discussions

Postby suryag » 21 Oct 2010 07:02

Test flight update only 3 flights in as many weeks :(

LCA-Tejas has completed 1452 Test Flights successfully. (18-Oct-10)
* (TD1-233,TD2-305,PV1-242,PV2-173, PV3-234,LSP1-60,LSP2-160,PV5-17, LSP3-16,LSP4-12)
LCA-Tejas has completed 1449 Test Flights successfully. (24-Sep-10)
* (TD1-233,TD2-305,PV1-242,PV2-173, PV3-234,LSP1-60,LSP2-159,PV5-17, LSP3-15,LSP4-11)

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Re: LCA News and Discussions

Postby Kartik » 21 Oct 2010 07:10

shiv wrote:Prodyut Das is a lateral thinker. He does provide some great insights and alternative viewpoints - but his ire seems to be directed at fossilized thinking and his attitude can be summed up by "Better to have working third generation in large numbers than attempting fifth gen and not getting there at all. He justifies this by saying that all the 100 or 200 to 1 kill ratios that are advertised break down when you have 4:1 or 6:1 advantage in numbers and quotes examples to boot.

Nobody can know the truth - but what Prodyut Das does is to ask if huge investments and long periods of time chasing the unattainable cannot be replaced by doing what is achievable reliably today and asks why nobody among the defence research set up are even looking at that possibility.


So is Carlo Kopp. yet we know that he has an agenda to run which he does through his articles. Actually Mr Das himself suffers from fossilized thinking, constantly looking for examples from the time he was probably actively involved in aero programs. Mr Das seems to have an axe to grind and he is doing so at the expense of the morale of those who work in the defence establishment. To paint everyone in those orgs as incompetent and no even able to understand the basics of aerodynamics that he recites is rubbish. Shiv sir, I've interacted with guys who were part of the design team. 2 of these were guys who were educated in the UK in the 1960s and chose to come back to India and work at HAL. Damn competent and very humble. Others from IIScs, IITs, etc. This type of an article is almost like Mr Das believes that he is the only smart thinking Indian aero engineer and the rest just goof around. Every other private sector company in India that works in aerostructures, avionics, etc. basically only poaches talent from these orgs and then channels them rightly.

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Re: LCA News and Discussions

Postby Surya » 21 Oct 2010 07:11

One only needs to see what happened to Vampires -

Ywah strap him to a Gnat and send him towards a F 16

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Re: LCA News and Discussions

Postby Kartik » 21 Oct 2010 07:15

Surya wrote:One only needs to see what happened to Vampires -

Ywah strap him to a Gnat and send him towards a F 16


don't you know that the Gnat is stealthy by virtue of its size and hence will be unspottable by the F-16? Oh and better send it up in the day only and when the weather is fine and clear, since he believes an LCA should be a day fighter (even in our times!).

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Re: LCA News and Discussions

Postby shiv » 21 Oct 2010 07:34

Kartik wrote: This type of an article is almost like Mr Das believes that he is the only smart thinking Indian aero engineer and the rest just goof around.


This particular criticism is valid judging from his last 2 Vayu articles. As has been discussed so often before - All "design" offers a dozen or more different choices and every choice compromises on someting while adding value in some other parameter. After all those choices are made it is very easy for someone to come up and say "Nyahaha this is bad, that is bad". Das tends to do that and it hurts. Prodyut Das is setting up a strawman for the LCA by doing back of the envelop calculations comparing Gripen and LCA and then arriving at weights that the LCA "should have". Once he has done that - anyone can look at the LCA in 5 years time and give it a Prodyut Das score and say "Failed".

Das's knowledge is admirable but he has a chip on his shoulder. He really must learn to leave out the bitterness when he criticizes. There are two aspects IMO to intelligence. One is knowledge and the other is communication. As a layman enthusiast I would score Das 90% on knowledge but only 40% on ability communicate without pissing people off.

Having said that I still enjoyed reading that LCA article for the insights it seems to offer on the thinking processes of other design teams, their successes, their failures and their compromises.

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Re: LCA News and Discussions

Postby Karan M » 21 Oct 2010 07:42

Shiv wrote:Prodyut Das is a lateral thinker. He does provide some great insights and alternative viewpoints - but his ire seems to be directed at fossilized thinking and his attitude can be summed up by "Better to have working third generation in large numbers than attempting fifth gen and not getting there at all. He justifies this by saying that all the 100 or 200 to 1 kill ratios that are advertised break down when you have 4:1 or 6:1 advantage in numbers and quotes examples to boot.

Nobody can know the truth - but what Prodyut Das does is to ask if huge investments and long periods of time chasing the unattainable cannot be replaced by doing what is achievable reliably today and asks why nobody among the defence research set up are even looking at that possibility.


Shiv, with due respect Prodyut Das is not any lateral thinker or de novo conceptualist. Swarming superior platforms is a tactic that has been around for ever, and only works if you are willing to put up with heavy attrition as the Iranians discovered with their mass attacks against entrenched Iraqi troops. There is a good reason whenever the topic comes up nowadays, folks mention unmanned vehicles not manned platforms.

Nor is it a new concept when applied to fighters. Pierre Sprey, one of the famed fighter mafia architects who were behind the original "light" F-16 has been running a campaign against expensive fighters like the JSF and F-22. The USAF evaluated whatever he said and said, effectively, sorry, times have changed. Same holds true for the IAF which is now proceeding towards higher technology items such as the PAK-FA and MMRCA. The reasoning is sound. Air Defenses have become well nigh, very dangerous.

Second, "the better there be many number of 3G than a few 4G platform" approach was tried in Bekaa Valley by the Syrians. They sent up many many MiG-21s, 23s and other fighters against Israeli AF F-15s and F-16s who slaughtered them. The "edge" was due to the fact that the newer fighters had much more expanded maneuvering envelopes and were deadly when flown by competent pilots and the Israelis had all aspect heat seeking missiles. It was a turkey shoot.

Point is Prodyut Das is good at gas-bagging when his life is not on the line flying his flights of fancy in today's lethal wartime environment, and nor is he a participant in the LCA program to accurately depict its competing push's and pull's in terms of technology.

A few years back, there was an IAF study that pointed out that anything greater than 2% attrition per effort has a pretty bad effect on air ops and is not sustainable. Sending hordes of primitive fighters against much more advanced platforms is a recipe for disaster, not to mention the impact on the most precious resource, the limited pool of trained fighter pilots.

Lastly, he assumes that everyone else apart from him, is a doofus. And the people developing the LCA are time wasters and need to be shown up. This is a typically ego centric attitude displayed by those whose whimsical ideas are rejected and then they go off an ego trip to disparage others.

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Re: LCA News and Discussions

Postby Karan M » 21 Oct 2010 07:45

Surya wrote:One only needs to see what happened to Vampires -

Ywah strap him to a Gnat and send him towards a F 16


Exactly, Vampires versus Sabres at Chamb, wasnt it. And what was the result.

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Re: LCA News and Discussions

Postby shiv » 21 Oct 2010 08:01

Karan M wrote:Point is Prodyut Das is good at gas-bagging when his life is not on the line flying his flights of fancy in today's lethal wartime environment, and nor is he a participant in the LCA program to accurately depict its competing push's and pull's in terms of technology.

A few years back, there was an IAF study that pointed out that anything greater than 2% attrition per effort has a pretty bad effect on air ops and is not sustainable. Sending hordes of primitive fighters against much more advanced platforms is a recipe for disaster, not to mention the impact on the most precious resource, the limited pool of trained fighter pilots.

Lastly, he assumes that everyone else apart from him, is a doofus. And the people developing the LCA are time wasters and need to be shown up. This is a typically ego centric attitude displayed by those whose whimsical ideas are rejected and then they go off an ego trip to disparage others.


The viciousness of Das's language suggests a chip on his shoulder or that he values his own views over anything else. Ironically the point you make about attrition pinpoints one of the strawmen that Das has set up.

The LCA team have been very cautious. When an airline (say the much advertised QANTAS) has a 100% safety record, do you call that airline "overcautious"? In the same vein the LCA development team cannot be called overcautious. They have played it safe where possible and that has led to delays and penalties as much as anything else. Now Das utilizes those delays to be scathing by saying that third gen (he had quoted scaled up Canberra bomber in his last article and scaled up Gnat in this one) could have been adapted rather than waiting forever.

But once again I must point I do enjoy it when he points out how other design teams in other countries made compromises and how some teams have have used hype, smoke and mirrors to sell snake oil. I particularly enjoyed his alternative takes on stealth, supercruise and FBW. The story is eerily similar to claims made by medical drug companies about "the latest and greatest miracle drug" being pushed until the cash registers start jingling. And Das is correct in recalling how FBW (with F-16) proponents gawked when they saw the MiG 29.
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Re: LCA News and Discussions

Postby shiv » 21 Oct 2010 08:18

Another point that Das makes is probably valid in the Indian bureaucratic set up

Let there be no awards until the weapon enters service fully. Let there be no "Distinguished scientists". It is better for everyone concerned to deserve an award and not get it than to get an award and not deserve it"
....
"Encouraging" the mediocre by possibly unmerited awards has got us where we seem to be in weapons research. Such awards have encouraged mediocrity to continue."
.

I believe what he says is true - knowing how these awards are given and who receives them. In fact this statement is a blow in favor of those who work hard only to see mediocre sycophants getting the limelight as is the case in most government set ups.

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Re: LCA News and Discussions

Postby Neela » 21 Oct 2010 11:00

vcsekhar wrote:Has anyone read the latest vayu article by Prof. Prodyut Das. Seemed like a complete hatchet job by him, although i am not an expert on aircraft design and can't really comment on the specifics but it followed up on his usual line of aircraft are too complicated these days and too heavy for performance etc etc.

However, i have spoken to fighter pilots who have spent some time on the LCA project and they all had a pretty high opinion of the LCA and also on the Mirage 2000 (the prof also thinks poorly of M2K too).

cheers..


I had saved this draft yesterday but could not post it.
-------------------------------------------------------------
I read it. And found it quite difficult to follow.


In the opening page, he says that a light fighter is not flown by light pilots and therefore it takes a "large" chunk away from the rest of the aircraft. But he could have justified it with some ratios with other aircraft. That he doesn't. He makes a huge leap in then arriving at the conclusion that it must be less equipped. Flimsy theorybut a strong conclusion

His comparisons are all with aircraft decades older than the LCA. Does he not realise that over decades, many components have become smaller and lighter.
The second page - well , defining what is the right technology in the best of times is quite difficult. And each and everyone has an opinion on that. So does Prof.Prodyut Das.
Pages 3 and 4 were about similar aircraft .

Page 5 - he is not happy with the look of the aircraft and whines that a dorsal air scoop has ruined the looks of the aircraft. This he attributes to disinterest or inability on details.


Further, in the subsequent pages, he has forgotten what the original purpose of the LCA was. To me he looks like a kid who has waited for his laddu and after seeing it, wants it in different colors,shapes and sizes.
Thereafter pointless ramble only. He starts giving marks based on weight. That perspective is quite narrow and about 8 years late. Had he said this years ago, he would have been an INdian aviation visionary. Bringing that now makes him look ordinary and like a person with an agenda.
What needs to be highlighted is the planned roles and mission objectives the LCA was intended for and how well the first IOC-ed aircraft will accomplish it. Simples. He takes a few corner conditions and explains that these are things it cannot do. Unfair and plain stupid.

And why the flamboyant, pompous language and references to things to highlight his span of knowledge. In my PG, I have seen professors who want to get the message across and explain things in a simple , elegant manner even though they were very very good at English. I am no expert on this personally but I find him to be a some kind of impostor who puts himself in shoes well above his size and making claims. Where was he all this time?

We have the IAF vouching for it now. Firm orders there. Engines ordered almost ordered. When the most important parties are all satisfied, why put your neck out. Seriously , why?

BUt I can see the pattern here. During development, it was the delay that was repeatedly criticized. Now that stage has passed and what else do they have? The aircraft design itself. I am willing to bet on what the criticisms will be for MkII. It will be a) delay and more shrill ones because they now cannot claim no experience any more. b) The new features on MkII will be deemed inadequate and does not justify a revision
Last edited by Neela on 21 Oct 2010 12:02, edited 1 time in total.

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Re: LCA News and Discussions

Postby Nihat » 21 Oct 2010 11:57

Besides, with the development of LCA Mk II the term "Light combat Aircraft" for Tejas is mis-leading in itself. A true blue multi-role fighter cannot be Light. Sure compared to other aircrafts its weight can be classified as lighter or heavier but the concept of Light fighter is something which quite possibly does not lie at the core of development of Tejas today.

If the airforce wants the fighter to carry a significant payload of LGB's, give higher thrust, carry modern missiles like R-77 and Astra, have an AESA on board then certainly the weight will increase. The professor's over emphasis on weight is a moot point and too late in the day as someone pointed out earlier.

LCA is probably not the right term for Tejas now.

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Re: LCA News and Discussions

Postby Avid » 21 Oct 2010 17:35

Skeptics such as Prof. Das play a constructive role by challenging the mainstream opinion in any new product development -- change for change sake must be questioned to obtain the key reasons meriting the change. Unfortunately, too many of them do not understand the difference between challenging and derision. Also, challenging opinions is constructive, but digging heels in with everything and "I am right!" is detrimental. Prof. Das has crossed far over from healthy skepticism to derision mixed with egotistical heel digging.

1. No new aircraft development has ever (to my knowledge) come under target weight. There are some innovative ways to perhaps undertake weight reduction as JSF had in 2004. Essentially one of the earliest successes in crowd-sourcing. http://dl.dropbox.com/u/3346049/WeightW ... -LMJSF.pdf
Perhaps ADA ought to consider a parallel LCA MK1+ approach for refining the MK1 through such "tinkering". This would result in improvements in the aircraft, and these can be fed into MK2 also.

2. Functional requirements specified by IAF are two-fold. a) at the level of individual aircraft, and b) at the level of the fleet. It is a fallacy argument to suggest compromising individual aircraft level requirements and showing that these requirements overall can easily be met by changing fleet size. It is dishonest argument because it easily overlooks how grossly he is compromising the fleet level goals.
Increasing numbers may allow accomplishing of the "goals" as he puts it -- but what does it do to the operational cost? what does it do to number of pilots required? what about logistics? what about maintenance? what about turn-around time during war? what about complexity of coordination during operations?

If he wants to make a case for completely alternate design + fleet size, he bears responsibility to produce an overall picture that meets all the goals but comes in at same or lower cost, in same or earlier time. Then I would humbly bow to his knowledge and assertion that he knows better. Short of that, he can claim only an opinion and an open question. Not state conclusion of a superior solution.

IMO, too many arguments about aircraft/tanks/etc. e.g. Rafale is better than Gripen type arguments, make 1:1 comparison and overlook the broader implications.

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Re: LCA News and Discussions

Postby Philip » 21 Oct 2010 18:20

The learned Prof's style and substance remind me of an old book on how to write better English.The author said one must "speak Chinese"!
"Man bite dog,dog bite man" or whatever,getting directly to the point using the least amount of verbiage.That is exactly what any successful project requires,getting to the goal in the least amount of time,using the least amount of resources and sacrificing the least amount of design parameters while getting there.

When viewed in that context,the LCA has -let's be honest and accept the fact,"failed to deliver".It was meant originally to replace the hundreds of MIG-21s at low cost and take advantage of the technological advances,composites,FBW,BVR missiles,etc.and should've entered service in the last century.Its Achiiles Heel was that of the Kaveri engine,which delayed its development beyond excuse.The mismanagement of the project,which had no "hire and fire" boss (thanks to the MOD/GOI),who could take urgent decisions saw its being headed by a "committee" of sorts,boffins,babus and on occasion a uniformed IAF officer,while the politicos kicked it from time to time like a football.One can understand the learned Prof's angst at this,I've heard it in great detail from many a uniformed officer,including a VCoAS too.

Nevertheless,as some have rightly said,change has taken place over decades and one cannot fight today or tomorrow's war with the equivalent of bows and arrows,especially in the air.What is required in developing our air force and developing and producing our aircraft of the future is not another "Gnat" to fight our wars,but to use the concepts,clear mindset and systems responsible for making the Gnat, MIG-21,Spitfire,whatever, a success instead. Therefore,with regard to the LCA,the urgent need is to get it into service MK-1,asap,let it have limited capability,fly it to its limits and then see what is required to make MK-2 relevant given its long gestation,the "creep" of obsolescence inthe design and the scenario faced by the IAF a few yars hence when we would've had the MMRCA in service and the on-going development and future arrival of the PAK-FA.During this time,our mortal enemies would not have sept,the Chinese appear never to need any sleep at all and have their own ambitious plans to devlop their own stealth fghter.But as Schumacher said,"small is beautiful".We know that from the success of the Nano.

I wish that the IAF/MOD/DRDO take a holistic view of developing a truly sound aerospace industry-as well as other defence systems that is/are indigenous.We now appear to have the money.Why can't we experiment? Why not develop two prototypes of the LCA with both GE and EJ engines? Other nations have done the same to find out which serves them best?Why aren't we developing prototypes of catamarans,trimarans,SWATH ships,etc.? The HVF keep on showcasing Tank-EX.They could also develop a light tank with a large gun specially useful for the Himalayas/mountains.As Shiv said,the learned Prof. is trying to think laterally,outside the box,and wants us to reroute mentally "back to basics".Some ideas might seem ludicrous,but tell that to the Wright Brothers ,inventors of cheap home made rockets and the inventors of Virgin Galactic.

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Re: LCA News and Discussions

Postby Avid » 21 Oct 2010 18:51

That is exactly what any successful project requires,getting to the goal in the least amount of time,using the least amount of resources and sacrificing the least amount of design parameters while getting there.


I suppose you are not a believer in things such as uncertainty, risk management, or adaptive project management.

What you suggest has all the rings of Prof. article! The statement in itself cannot be refuted, or rejected. Who in their right mind would not want that? But the presumptions are monumental! You can do all of that only and only if there is minimal uncertainty in what is being made, and there is no learning or new knowledge requirements.

Why can't we experiment? Why not develop two prototypes of the LCA with both GE and EJ engines?


Goes against your own suggestion above. You cannot lay down a principle of least resource, least time, least sacrifice and then suggest two prototype developments. They violate time and resource requirements you have put as cornerstones. Time because you have added on more stage to the development -- comparison of performance overall.

Experimentation by nature is associated with things uncertain and learning requirement. It comes with failures and corrections, and adding experimental developments and revisions would significantly add time (not to mention gazillion more tsk-tsk opinions such as yours on BR -- "I know better than all other people who are complete idiots and missing something elementary").

Slightly paraphrased quote that many all-knowing folks ought to consider before the suggest solutions that have all the seemingly obviously common-sense in what they say:
There is always an easy solution to every complex problem
It is neat,
It is plausible, and
It is wrong.


Sorry, if this is harsh. But, I am growing weary of the exponentially increasing posts that are offering "simple, easy, neat and plausible solutions" to all problems from LCA (make modified Gnat!), MRCA (buy JSF!), C-17, C-130J, on and on and on.

Hope against hope, I wish this would make some pause before they post their simple, easy, neat and plausible solutions with "I know, I know" / "mujhe pata hain" / ...

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Re: LCA News and Discussions

Postby Vivek K » 21 Oct 2010 21:55

What people are now talking about i.e. improved Gnat or modified Mig-21 shows a mentality stuck in the 80s. Check the date, we are approaching 2011 i.e. 3 decades have passed since then. A lot has changed in the requirements of a military aircraft.

Improving the Mig-21 to be multirole with longer legs IFR capability, larger weapon load would have added a huge amount of weight to these aircraft. This wold require a new/bigger engine, redesign of the airframe (and the intakes) and of course the IAF would have asked for a 100KN engine. All of this would have lead us to where we are today. The LCA is the answer for most of IAF's requirements based on our current tech level. MK2 requires an upgrade of tech capabilities and therefore extra time.

Therefore what is being written today about the LCA is by learned people who in this case are talking out of their wazoo! Please stand aside and the LCA and NLCA take flight. Let us learn from these designs and study and compile all our mistakes. MK2 will address some of these and some may take a MK3.

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Re: LCA News and Discussions

Postby Singha » 21 Oct 2010 21:59

hawks...listen for a distinct smooth liquid swishy noise....ge404 is more screaming and piercing noise...hawk RR is like single malt -smooth and peaty

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Re: LCA News and Discussions

Postby Kartik » 21 Oct 2010 22:47

I suddenly remembered something and I am not the conspiratorial type at all. But this was just too much for me to just pass of as being mere coincidence.

Just about a month ago, there was an India Today magazine Saab company Gripen supplement that had articles by 3 or 4 different Indian authors, all basically praising the Gripen NG and how wonderfully the Swedes had done on this program and the lessons for India..They included Pushpinder Singh Chopra (Vayu magazine's editor) and (voila !) Prof. Prodyut Das with an article called "The Swedish Way"! It was a supplement paid for by Saab. A few months before that, Pushpinder Singh was in Sweden telling the local press that the Gripen NG was a favourite to win the MRCA competition.

I am now convinced that the timing of Prof. Prodyut Das' article on the LCA, totally trashing it as being a failure (Grade F) and suggesting that it be dropped, or pursued with very little vigour, is no coincidence. It appears just a month after Prodyut Das praises the Gripen NG to heaven in that supplement.

So, there you go- this article was nothing more than a hack job, at the behest of one of the companies competing for the MRCA, and one which many of us (and many of the IAF and DRDO) compare to the Tejas Mk2 the most.

IMO, this is one of the most glaring examples of journalism being used to influence mindset and an attempt to subvert a national program at the behest of a foreign company.
After all, Vayu will definitely have a large circulation amongst current and retired IAF officers and MoD boffins.

Others on BRF have told in the past that the Saab Gripen NG if chosen, will definitely spell the death-knell for the Tejas Mk2 because the IAF will be told that they could simply order more Gripen NGs instead of having to hand-hold DRDO/ADA on developing and ordering any more Tejas Mk2s. Now I'm convinced that is EXACTLY what is likely to happen if the Gripen NG is chosen.

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Re: LCA News and Discussions

Postby nachiket » 21 Oct 2010 22:51

Nice catch Kartik. So the esteemed "Professor" turned out to be little more than another Lifafa journalist. :lol:

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Re: LCA News and Discussions

Postby Indranil » 21 Oct 2010 22:53

I know Dr. Das champions the cause for a simple fighter.

But I don't think he meant to send Gnat-Mig21 morphs into 2011 aerial combat. He speaks about those in the section, "What LCA could have been". At that time 80s, we were looking for a cheap replacement for the Gnat and the Mig-21. To provide for the same through a simple morph taking best of both worlds should have been the first step which could have been done in 4-5 years. There are precedents to it.

Once we had that cheap and aerodynamically superior plane in 85-90s in numbers, we could have refined it or designed a new plane based on lessons learnt. Instead we chose to build a plane ground up which spelt light, but chose a planform which would inherently need FBW (back in the 80s itself). Also we believed that we would be able to come up with an engine of Kaveri's complexity within 10-15 years! These were flaws in decision making, which have manifested. I mean the delay is there for everybody to see. Dr. Das says that choosing this all new configuration almost mandated this delay given the development time needed by other countries as well.

Then he moves on to what LCA's objectives could have been. It was initially never meant to be a top of the line strike or air dominance fighter. It was supposed to be an agile light fighter, which would make up for the lower part of the high-lo mix. In that respect he specifies some characteristic tradeoffs. But frankly I believe he got carried away with the aluminium part.

And lastly he tries to set benchmarks and gives out grading scheme typical of a professor.

However, in the article, one can't but admire the view of the author. He gives ample examples of how a "light" fighter should be. His primary objection in my opinion is not that we should simplify everything down to the fly. However, as a first step to build a light fighter, he opines that we should have gone incrementally rather than ground up. That clearly was an alternative we chose against.

Kartik, I think he brings out the dorsal air intake for aesthetics. Between do you share my view that may be a vertical intake morphed with the tail might have been less draggy? Also the vertical intake like the one on Kfir will provide air from further away of the boundary layer and hence would generate a steadier and smoother stream for cooling?

Besides is there a reason known in open literature why the nose undercarriage is directly under the pilot?
Same goes for why wasn't the cross section tapered inwards from the plane of the antenna (Radar antenna) to smoothly blend into the plane of the intakes?

I can only speculate some reasons, but I don't know the exact reasons. Please post if you know the exact reasons. Thank you.
Last edited by Indranil on 21 Oct 2010 23:03, edited 1 time in total.

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Re: LCA News and Discussions

Postby Indranil » 21 Oct 2010 23:01

Kartik wrote:Others on BRF have told in the past that the Saab Gripen NG if chosen, will definitely spell the death-knell for the Tejas Mk2 because the IAF will be told that they could simply order more Gripen NGs instead of having to hand-hold DRDO/ADA on developing and ordering any more Tejas Mk2s. Now I'm convinced that is EXACTLY what is likely to happen if the Gripen NG is chosen.


I like the Gripen IN configuration a lot and feel that it is in fact one of the best fit for the MMRCA. But even I share the fear that it might sabotage LCA MkII similar to what Jaguar did to the Marut.
And the bigger problem is that Gripen IN having assured market with IAF, it would make more financial sense for HAL to churn out more Gripen INs from a (then) established line, rather than grind on with uncertain orders for LCA Mark II.

One promising thing though is that engines have been finalized (almost) for atleast 100 Mark-IIs. So there is a definite push for the LCA Mark II.

And of course for me the best situation is get 200 Gripen INs. LCA Mark II does really get IOC by 2014-2015 and proves cheaper than the Gripen IN. An indigenous and cheaper system to much pass on :).

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Re: LCA News and Discussions

Postby Cybaru » 21 Oct 2010 23:14

Oh my goodness, that is one crappy, boring, pompous article worthy of not even a complete read. He lost me with his wife beating raddi-wallah smart alec comment. There are thousands of these, I know whats good for you all kind of folks out there. Ignore maaadi...

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Re: LCA News and Discussions

Postby Indranil » 21 Oct 2010 23:54

^^^ Its not that bad I believe. It is loaded with information. You can always ignore the criticism if you don't like it or find it meaningless. You can always absorb the rest :)

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Re: LCA News and Discussions

Postby Surya » 22 Oct 2010 03:32

Sad part is many well known famous defence journalists are all lifafa :(

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Re: LCA News and Discussions

Postby Kartik » 22 Oct 2010 04:08

indranilroy wrote:I know Dr. Das champions the cause for a simple fighter.

But I don't think he meant to send Gnat-Mig21 morphs into 2011 aerial combat. He speaks about those in the section, "What LCA could have been". At that time 80s, we were looking for a cheap replacement for the Gnat and the Mig-21. To provide for the same through a simple morph taking best of both worlds should have been the first step which could have been done in 4-5 years. There are precedents to it.


Indranil, there was a GnatII out there in IAF service back then- the Ajeet. Check for yourself just what happened to it. Ended up being a very mediocre fighter and thoroughly outdated by the mid 1980s itself when the IAF was introducing Mirage-2000s and MiG-29s and contemplating which one to licence produce in numbers. Even before that, avionics wise it was outdated compared to even MiG-23s and Jaguars. An LCA that would've been a "Gnat-II" type fighter would've faced the same dismal future in the 1990s when the IAF would've said that this was already "obsolescent" (meaning not yet obsolete but quite rapidly approaching it).


Once we had that cheap and aerodynamically superior plane in 85-90s in numbers, we could have refined it or designed a new plane based on lessons learnt. Instead we chose to build a plane ground up which spelt light, but chose a planform which would inherently need FBW (back in the 80s itself). Also we believed that we would be able to come up with an engine of Kaveri's complexity within 10-15 years! These were flaws in decision making, which have manifested. I mean the delay is there for everybody to see. Dr. Das says that choosing this all new configuration almost mandated this delay given the development time needed by other countries as well.


We had that Gnat derivative in service already and it was a dead end, product upgrade wise. You cannot forever keep taking existing designs and make refinements to it and hope to keep developing newer variants. That is akin to the J-7 series that the Chinese have forever been modding and coming up with new variants of. Now, the F-7PG is the final variant and no one, not even the poor customers who were interested in J-7 types are interested in the latest variants that introduce new ventral intakes and pointed radome, akin to newer fighters. So, the J-7 is basically arrived at its dead end.

Many people object to the F-16 Block 60 saying that the F-16 is fast approaching the end of its evolutionary cycle and no more major upgrades or variants are possible without doing some serious surgergy to its airframe. At some point, a clean sheet design is required to meet newer requirements that Air Forces come up with.

And why only accuse the DRDO of being too influenced by latest trends? Aren't people accusing the IAF too of being the same (such as the supercruise debate and whether it is of any real use or not?) the US boasts about the advantages of AESA and suddenly everyone wants it. PESA is quite good but now approaching its evolutionary end.

Choosing a fighter that required FBW is not something bad. Keep that in mind. No 4th gen fighter (with the type of roll/turn requirements considered standard nowadays) worth its name has mechanical controls or is statically stable. the MiG-29 and earlier Su-27 are worthwhile exceptions but the Russian superlative aerodynamic strength is not something that just happened. They've been through countless aircraft types and variants and have honed their skills and knowledge in that field. Our experience is basically the HF-24 Marut and even that design was basically Kurt Tank and his German engineers'.

If the LCA was not FBW, that would've been an object of derision today, I'm very sure about that. The mistake made was to go with quad redundant with US support and lose Dassault's help.

As for the Kaveri, it was too ambitious and they gave it a try. It failed to achieve the targets set, ok, and now the Tejas program is de-linked from the Kaveri. What else can one do? Hang the guys who spent their careers working on it or publicly berate them as being inept and incompetent so that it scares away every other competent guy who wanted to stay in India and work in DRDO? Does that solve the issue? Can M&M, L&T, Tata or whoever come up with an engine in 10-15 years without basically doing some "JV" where the part is basically the same as the foreign one, but made in India and with an Indian name ? No way. I mean look at what PZL's exec said about M&M ("they don’t have experience in aviation industry").

Or just look at the automotive industry- they have been basically "tying up" with foreign firms (Suzuki, Renault, Peugeot, you name it), basically getting their designs and only building it in India. All except Tata and we know how bad the Indica was in its initial versions. Noisy, vibrated a lot, was totally unrefined. If I'd sat down and compared it to Saab 9-3, 9-5 or Volvo S40, S60, S80 or other cars, they'd be weeping at Tata Motors. But the Indica was cheaper (as is the LCA compared to Gripen), did the job and eventually got all its major problems sorted out. Now it’s a damn popular car.

So we can hope that if Snecma "ties up" or helps GTRE, at least we'll have a working engine. How is that any worse than Volvo Aero basically taking US engines and doing some mods here and there and using it for the Gripen and Gripen NG ? the mistake was that the political leadership should set the targets very clearly. Get a fighter in service by 2000 and money is no object and indigenisation is no object. Then you can safely assume that they'd have sub-contracted 60% of the fighter to foreign companies and by early 2000s the LCA would've been in service.

Then he moves on to what LCA's objectives could have been. It was initially never meant to be a top of the line strike or air dominance fighter. It was supposed to be an agile light fighter, which would make up for the lower part of the high-lo mix. In that respect he specifies some characteristic tradeoffs. But frankly I believe he got carried away with the aluminium part.


The Aluminium part is not new from this man. He has in the past also advocated not using composites. That is his opinion. IMO, it’s not that great an idea, but hey that’s my opinion. the Chinese designed an all aluminium plane to lower design loads and it still weighs as much as the Tejas. Maybe no advantage but no disadvantage either.
And lastly he tries to set benchmarks and gives out grading scheme typical of a professor.

However, in the article, one can't but admire the view of the author. He gives ample examples of how a "light" fighter should be. His primary objection in my opinion is not that we should simplify everything down to the fly. However, as a first step to build a light fighter, he opines that we should have gone incrementally rather then a ground up. That clearly was an alternative we chose against.

Kartik, I think he brings out the dorsal air intake for aesthetics. Between do you share my view that may be a vertical intake morphed with the tail might have been less draggy? Also the vertical intake like the one on Kfir will provide air from further away of the boundary layer and hence would generate a steadier and smoother stream for cooling?


How do we even know what is the thickness of the boundary layer at that distance from the forward fuselage ? Drag may very well be a very very small penalty for a more well-designed intake. My point is that its fine for the author to have pointed out what may be a design issue (I'm not saying the dorsal intake is a design issue) and give reasons for it, but the manner in which he calls it something that would upset the sensibilities of a raddi-walla (and thus implying that those who designed it even worse) and proof that design is half-hearted is ridiculous. I mean this is a subjective topic. I may find it damn attractive, he may find it an eyesore.

Besides is there a reason known in open literature why the nose undercarriage is directly under the pilot?
Same goes for why wasn't the cross section tapered inwards from the plane of the antenna (Radar antenna) to smoothly blend into the plane of the intakes?

I can only speculate some reasons, but I don't know the exact reasons. Please post if you know the exact reasons. Thank you.


Indranil, there are many factors that influence how and where the landing gear is located. Some of the factors are that there should be no tail strike when landing such that the angle of attack of the a/c is such that 90% of the wing lift is developed. This is mostly at take off rotation.

Look at the length of the fuselage on the LCA. one thing is that the main landing gear is generally placed aft of the CG to keep the aircraft stable and to ensure that there is no "tail-tipping" when you brake the aircraft. Basically to prevent the tail from tipping over backwards.

Now, once you've located your MLG based on the CG location of the aircraft, you need to work your way backwards to locate the nose wheel. The nose-wheel location is decided based on the "track" and "wheelbase" (track being distance between MLG wheels and wheelbase being the distance from nose wheel to MLG wheels). There are design rules to keep the aircraft stable from turning over sideways during a turn at 0.5g lateral acceleration. This means that the turn-over angles should not exceed certain angles. I can't remember exact values but they are around 60 deg or so. Again, carrier aircraft have different turn-over angles than land-based aircraft. So, to get that value, you need to have the proper wheel base. Now, you can possibly alter the wheel base a few feet here or there and it will make only a small difference to your turn-over angle, but you have another factor to consider as well- that the nose wheel should have 8-15% of the aircraft's weight centered on it to allow for proper steering control.

Based on these factors, the nose wheel location is chosen. BTW, there is nothing wrong with the Tejas' nose wheel location. the Mirage-2000 has the nose wheel slam bang under the pilot as well and I've never heard anyone criticize that location.

Regarding the tapering of the fuselage from the widest point on the radome to the intake, well that would depend on two factors- how much the fuselage length was and how wide your radome is. If you had more fuselage length and such a method allowed for sufficient narrowing of the fuselage to give you some aerodynamic drag relief, then it might be worthwhie to pursue (Mirage-2000 has some such taper, don't know exact angles). But, the Tejas' fuselage before the wing root starts, is quite short in length. So it is questionable as to how much improvement in drag there will be, if at all.

Then again, the Tejas' radome at its widest point is 650 mm or so (quite big for such a small aircraft). The cockpit begins quite close behind the radome. How much can you taper it to even see any sufficient gains? If you taper it as much as 7 deg, it will reduce cross-section at the cockpit region and in turn reduce the internal space and volume of the cockpit making it more cramped than it already is.

basically, its all about trade-offs. You do one thing, something else is affected. Question is which "something" is more important.
Last edited by Kartik on 22 Oct 2010 06:32, edited 1 time in total.

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Re: LCA News and Discussions

Postby D Roy » 22 Oct 2010 04:58

Excellent post by kartik as usual.

Bottomline: The damn envelope was pushed on every aspect of the LCA project without throwing the necessary amount of cash, having the most experienced program managers for this kind of thing and being subject to technology denial regimes.

Despite all that the Indian aerospace sector now finds itself in a situation where it is 80-90 percent on the latest technology.
Given that money is now available as is enthusiasm in aerospace that last excruciating ten percent will be made up and in things like mission computers and other avionics it has been made up, I daresay.
'
We must remember that warts and all our nation's philosophy has always been true strength. So the IAF instead of excepting a Mark-0 display plane as the PLAAF would do just to show that Chicom is "capable of putting up modern fighters" was willing to be patient to make a product evolve to a stage where it would remain contemporary.

This is an important national difference. And despite all the acrimony the fact remains that the IAF is pretty much committed to the LCA.

And if I may be permitted to say so, just as the CWG and the Arjun project ultimately turned out to be more than decent so will the LCA.

The vayu article is the old indian mindset - aluminium, mechanical controls and other such nonsense. It doesn't even warrant discussion when we are already recognized for our work on composites and MFDs.

Better start developing fly by light technologies instead of lament about why we did FBW when a glorified system of magnetic levers would have sufficed.

Bill Sweetman at the last Aero India said that "India is a close aerospace power". I believe him.
Last edited by D Roy on 22 Oct 2010 05:05, edited 2 times in total.

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Re: LCA News and Discussions

Postby Indranil » 22 Oct 2010 05:02

Kartik thanks a lot for the reply. I am aware of the landing gear design principles and hence when I said I can speculate the reasons, my speculation was that LCA was not long enough to be trimmed down more and have enough internal space. But I didn't know whether that was the exact reason or whether there are other benefits of putting the nose wheel slam bang underneath the pilot. To be precise I didnt know whether it was a tradeoff or a design principle (which I am not aware of) being followed. However, your reasoning also adds weight to my speculation.

As regards to LCA being designed ground up with FBW, you have a very valid point, that any 4th gen fighter worth its salt is FBW. It is a very valid point. And I have openly fought with Shiv sir (whom I respect a lot) that technology by and large follows a certain direction because it is the next logical step and we shouldn't just go searching for a conspiracy marketing theory for everything. But I still have a feeling that we could have continued on building a plane ground up but could have come up with a morphed design for the interim. It would have given us very valuable lessons in optimizing (LCA Mark I would have been optimized rather than Mk II).

Also in the last 10 years India has suddenly seen a huge influx in money. What would have happened if we didn't have these billions of dollars to dole out as we have now. Clearly this couldn't have been predicted with any certainty in the 1980s. Can you imagine the limbo we would have been in if we couldn't buy the MMRCA and the extra Su-30s? Where would our squadron numbers lie in 2014-2015? That's why I believe that the decision to design a new plane ground up was a risky one.

Besides clearly I don't blame the GTRE guys for Kaveri. One would not find a single post of mine expressing any kind of regret/exasperation from my side on the "delay". They had been put up with a next to impossible task of building the engine from scratch and with no prior experience in times next to zilch. Nobody else would even take up such a high risk endeavour in first place. All I am saying that our first try shouldn't have been such a big one. In my opinion the delays are actually miscalculations in estimated time to design in first place.

Perhaps, we should have taken smaller hops and by now those small hops would have garnered enough experience to come up with a more "optimized" LCA. Very much like LCA gave us the knowledge base to go to Tejas MK II to go to MCA...

Again, I am very proud of the present LCA. It is just my humble introspection in hindsight. I believe it is always good step back and listen to critics once in a while. We lose nothing by listening to somebody. In that respect Prof. Das is not a bad critic, whatever be his motive.

GO LCA!

D Roy
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Re: LCA News and Discussions

Postby D Roy » 22 Oct 2010 05:11

Just for the record.


From The Economic Times
22 Nov 2008, 0245 hrs IST,
By Ian Q R Thomas

FOR the past 60 years, India has built a steady reputation as a nation with strong aerospace and defence capabilities, but it is a reputation which has been forged, for the most part, in splendid isolation. While a number of critical requirements have been fulfilled by indigenous aerospace and defence products, those same products have not been readily transferred to the world market.

That looks set to change, however, because all the signs are that India is poised to enter the global aerospace and defence economy, not with a whimper, but a bang. India’s place on the global aerospace and defence industrial stage will not be secured overnight, it will have to be earned. But this revolution is already underway thanks to a confluence of circumstances that play heavily in India’s favour.

Take its workforce, for example. At a time when western aerospace leaders are facing up to a dearth of engineering talent at home as the ‘Baby Boomer’ generation retires, India’s young population means that skill-sets laid down today will pay dividends over the next 50 years, not just in India, but globally. The fact, too, that the language of the global aerospace industry happens to be English is an enduring advantage that will also help Indian engineers plug quickly into the global aerospace economy.

India already has a solid manufacturing base, thanks to the prevalence of its automotive industry. While automotive is not ‘aerospace grade’ in terms of cost, quality and schedule, it is an excellent place to start. Tata, for example, recognised worldwide for its automotive prowess, is already emerging as a highly credible aerospace and defence industrial partner.

India is also a world leader in key areas such as IT, engineering, and research and development, disciplines that are core elements of a successful aerospace and defence ecosystem. Private sector companies such as Wipro, Infotech, Infosys, HCL and public sector undertakings such as HAL and BEL are poised to take the Indian aerospace industry to new heights.

As defence systems in particular become increasingly ‘network-enabled’, the buzz term that denotes the way satellites, aircraft
, ships and vehicles share data to promote greater battle-space knowledge and awareness, India is well positioned to play an important role in defining and building the system-of-systems architectures that are fundamental to modern defence networks.

Aerospace is an industry based on innovation, creativity, and advanced technical skills with a history of startling accomplishment, thus India’s focus on education and natural entrepreneurship fits nicely into it. In addition, the injection of the kind of entrepreneurial flair for which India is noted could even breathe new life into the aerospace and defence business globally.

It is, of course, the phenomenal surge in demand within India for civil aircraft and defence products and services that is providing the catalyst for rapid change in India’s aerospace and defence industrial infrastructure.

Whatever uncertainties may exist currently in global financial markets, India’s strong and growing domestic demand for civil aviation, more than a thousand aircraft worth in excess of $100 billion are needed over the next 20 years, continues largely unabated. The Indian government is also expected to spend a roughly equivalent sum on defence products over a similar period.

Aerospace and defence as a sector is notorious for its high barriers to entry and India will need to invest heavily in knowledge and innovation to ensure that its developing skills are not swamped by the established global competition.

The key to improving R&D in India is through strategic collaboration among government, industry and academia, building on the success of the public private partnerships that have been instrumental, for example, in the development of new airports and other critical infrastructure across India.

On paper, the fact that some 500,000 engineers graduate every year in India is impressive and is often quoted in the US and Europe as a reason why the west needs to invest more in its own school-age maths and science talent to produce more engineers of its own.

But the headline figures do not tell the whole story. India has only 200 ‘dynamic engineers per million’ as opposed to 750 in the US and 500 in China. Given that over 45% of India’s population is under 19 years of age, there is still everything to play for when it comes to the penetration of quality education in this demographic.

Training is another big ‘if’. The current mismatch in India’s ability to supply trained manpower to meet demand is highlighting a dire need to establish aerospace vocational training institutes in India. These would help fulfil the demand for the diverse skills that aerospace demands; skills that range from engines and airframes to networked systems and avionics.

Going further, and building on India’s automotive revolution, Indian companies are well positioned to leverage their established footing in global quality management systems, ISO, QS, TS and the like, to advance to aerospace standards that would cement these companies’ standing in the global aerospace arena.

From this would flow, too, a corresponding improvement in the country’s maintenance infrastructure, an easily assessable indicator of sectoral competence. One way of establishing competences in this and other key areas is to set up dedicated hubs or special economic zones where high-precision manufacturing, processing and assembly can be undertaken.

Government can play its role by setting in place policies and incentives to help India achieve the rapid growth of which it is capable. These include tax exemptions, concessions on excise duties and liberal foreign exchange regulations as well as other policies that incentivise global aerospace companies to join with their Indian counterparts.

These relationships are central not just to a thriving market for aerospace and defence goods in India, but to an eventual two-way sharing of technological capabilities, precision manufacturing and R&D. Given the enormous amount of aerospace work due into India in the next five to ten years, and the offset programmes related to it, this should help trigger the necessary investments.

But the public and private sectors need to invest in advance of this surge in order to get the right foundations laid, their people trained and the relevant risks reduced. If the above issues are addressed, India will have seized a unique op-portunity and graduated to a well-earned place as an important player in the global aerospace and defence industry.

(The author is president, Boeing India)

shiv
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Re: LCA News and Discussions

Postby shiv » 22 Oct 2010 06:12

On the topic of lifafa journalism - I had once spoken to the publishers of both Indian Aviation and Vayu (separately) about "sponsored" articles. (This was around 2001-2). They said that it was a fact of life. No journal can survive without them. So one must always be wary of articles in the media.

Prodyut Das knows more than I do. I am under no obligation to accept what he says - but nevertheless he says things that nobody else will say. If you ignore his comments about the LCA (which the entire world, with Indians in the lead, seem to curse and mock) you find that Das is saying nasty things about other non Indian designs and designers as well. That makes a change from the standard lifafa rahrah boys singing the praises of F-16, F-35 etc. And although late, Das often rips a new one about aircraft that were touted as latest and greatest in the 1960s and later.

Katare
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Re: LCA News and Discussions

Postby Katare » 22 Oct 2010 06:38

Cheap shots and mud-throwing by so many members on the poor professor. Remeber that a writer does not have to be correct/right or put mainstream view in his articles. He has all the rights to write what he believes even if it appears wrong or motivated to others. People should not judge and assign motives to others so casually on an open forum. Everyone gets paid for writing professionally, the once that can't get paid all come and write at BRF :mrgreen:

Anyhow most people, who are bitter, didn't even get the point or understood his thought process. They didn't get it because they are not confident in LCA as it is or blinded by love for the same.

Article makes sense, it is written very well and it is technically very accurate. His conclusions or thought process you can argue against but the article is of excellent acedemic standard.

He simply says -
A light fighter means a palne equipped with less gizmos. You can't take an MKI or F15 and scale everything down to 50% and end up with a light combat F15 or MKI. You have to start from other way and say what is minimum I must have to be competitive and relevant and let go rest of it aka tata nano, sold in same showroom as Luxary Jaguar, Safari and Land rovers.

Light fighters are designed only for affordability and numbers so they should be kept simple and type specific. All other jobs/duties should be assigned to other larger and well equipped but expansive planes in the inventory

Gnat and MigF as per his understanding were true light fighters and they were true and successful because they were basic with very little or no gold plating

He also cautiones against MNCs selling half cooked technologies and airforces falling for them just cause others have them. He gives some good examples although again total disdain for technology is shown but purpose here is to contrast his views rather than to trash the technology. He also thinks that numerical superiority should not be sacrificed for tiny fleet of uber tech toys.

Finally on LCA his views are logical and you may or may not agree with his conclusions but assigning motives and calling names only shows ignorance. I can only justify LCA based on "mother India must go through this labor pain to have a baby". Rest assured LCA was a mess, is a mess and would remain a mess for years.

So on and so forth ----
To make his point stand out he goes too far and people here are picking on those excesses but that is not the heart and soul of the article.

In the end I largely don’t agree with his views but I understand where he is coming from and respect that.


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