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why LCA resemble with mirage 2000 so much?

Because both are single engine, light weight, delta wing fighters, fullstop!

Crossposting from saumyasupratiks post in the LCA picture thread to show the clear differences to Mirage 2000:

notcopy1px.gif



IAF has good experience with delta wing design, be it with Mig 21s, or Mirage 2000s, that's why a similar wing design for LCA was very logical and why Dassault (as one of the moste experienced companies with this design) was added as a consulting partner in the the early design phase.


The Mirage is a simple tailless delta.

While the Tejas is a "cranked" tailless delta.


From DRDO:

The LCA integrates modern design concepts and state-of-the-art technologies such as tailless compound delta
platform
with relaxed static stability fly by wire flight control system and advanced composite materials for
structures. In addition open architecture avionics with advanced glass cockpit, hands on throttle and stick (HOTAS),
head-up display, active matrix multi-function displays and helmet-mounted display are integrated.

http://www.drdo.gov.in/drdo/pub/techfocus/2011/feb 2011 .pdf
 
The people whose names appear on aircraft types - Sukhoi, MiG, Mil, Antonov, Ilyushin, Boeing, Lockheed Martin, BAE, EADS - are known as systems integrators. They don't make planes in a factory where the nuts, bolts and composites are made; they call in assemblies, sub-assemblies and components from all over the world, subject to security and secrecy considerations, and put them together to a design. Sometimes, as in the case of the Russians, design and manufacture are separated, for greater integrity. Yes, the systems integrators and the designers, between them, retain the right to make changes in design and alterations and modifications, due to discoveries made during test flights, but this is the process.
Can you please sir throw some light on AESA development?
So you can gauge for yourself how ridiculous the entire agent provocateur post was.

Tyres have been made in Dunlop Sahaganj from the 50s; the legendary Suranjan Das' son was a Dunlop employee supervising smooth supply of these to HAL from the 70s onwards. Avionics, with which I have personal involvement, has been indigenous from the 70s and 80s onwards; the brilliant account of the DARIN conversion by T K Sen is a gripping story by itself. Composites were developed under the leadership of the technical genius Krishnadas Nair, whose lectures on composite technology drew packed audiences; his open lectures usually had a distinguished overseas delegation in attendance. The composite manufacturing effort was developed within HAL while he was Managing Director of the Bangalore Complex, well before his Chairmanship. Autocrat though he was, nothing should be subtracted from his technical contributions to the nation. The landing gear and its anti-skid braking software was developed by HAL engineers working within the ADA/ADE; my successor as CEO in the avionics firm was lead programmer for the ABS software.

I could go on and on, if not for the fact that we have gone into all this before. The crowning glory, however, was the writing of the flight control laws. It has led to a smooth, mellow flying machine which each and every one flying it has fallen in love with from the first flight onwards. Contrary to half-baked reports, the involvement of Lockheed-Martin was limited to intense technical discussions with a full team of Indian engineers, who started developing the control laws. They were locked out of their work-places literally at an hour's notice on the clamping of sanctions. All the work for the first version, which a member of the team says was slightly rough at the edges, typical for version 1.0 efforts, was left behind. The team went to work again from first principles, and the result is flying now. So much for Lockheed-Martin having built the control laws. For those who have read 'The Mythical Man-month', this illustrates the maxim that in a large software project, the first step is to make one to throw away.

There were failures. The worst was Kaveri, which was crippled by sanctions. Everything had been built around the supply of certain critical components. I am not sure that I should even talk about it. Another setback was the AESA radar development. And that was about it. For a ground-up effort, this was magnificent. Some tuppenny-ha'penny wet-behind-the-ears undergraduate should not cause such a storm of reaction unless we are ourselves actually ignorant about what happened. I am quite irritated at the slavish efforts still being made to try and convince those who have clearly set themselves up to have some fun at the expense of our more combustible members.
can u sir please throw some light on AESA development?what are the main problems it is facing and how much success we have achieved in this particular field.
 
Both of them are tailless deltas but that is where the similarity ends!


The Mirage is a simple tailless delta.

220px-Wing_tailless_delta.svg.png


While the Tejas is a "cranked" tailless delta.

220px-Wing_cranked_arrow.svg.png


thats 'Cranked arrow' - similar to a compound delta, but with the trailing edge also kinked inwards. Trialled experimentally on the General Dynamics F-16XL.

http://dc306.*******.com/img/s8-jwhsT/0.6235182629976099/gra6.PNG
 
@Joe Shearer

why IAF has been so figgity about LCA ??

A purely personal opinion: they have always apprehended having their budgets cut off by another pacifist Minister for Defence, so they have always compromised between air superiority and strike. Unfortunately, the Mirage turned out to be a genuine multi-role aircraft, something that turns up once in a blue moon, something like the F4 might have been, fitted with cannon. As a result, they want every new aircraft to be the Mirage. Every new plane has to be a multi-role plane, never mind that the two roles are so wildly different.

The LCA was planned as a light interceptor, the exact original role of the MiG21; while it was being developed, the IAF got jittery, thought it would replace all aircraft, including specialised ground attack planes (the Jaguars, for instance), and started building in specs which would meet those demands. In other words, they told the politicians, "If you want a plane that does everything, this is how it must perform. Can you get the boffins to make one that does all that? Then and only then can you replace all the types we have today with one LCA type tomorrow."

This plane was never designed for ground attack or for interdiction or for deep strike; when nervous people started sticking on extra requirements, everything went for six. For one, load-carrying capacity had to be increased; the fuselage size was increased; all the original optimisation went for a toss; there was serious hard work that went into getting things back on trim, and it has just been achieved. There was a time three to five years ago when the IAF thought it wouldn't happen after all; everybody has suddenly woken up to the fact that actually the plane does all that was planned.

Now they don't want DRDO and ADE in particular to get lazy, so from time to time, the Air Chief of the day makes a threatening announcement in public, saying that the plane still hasn't achieved full compliance. This is quite wrong and quite right at the same time; it is quite wrong because the Air Chiefs know very well that flight testing is a long-drawn out procedure, and everything is done incrementally, so that anomalies can be isolated to one factor, the one changed over the previous test (this is an exaggeration), so it will take time to meet every spec. requirement. It is quite right in that it serves as a reminder to the testing establishment that they must keep to the punishing time table or risk a delay. Nobody wants to think about the D word today.
 
can u sir please throw some light on AESA development?what are the main problems it is facing and how much success we have achieved in this particular field.

I am a little reluctant to get into this. Some information is still classified; most is, actually, and I don't want to play chicken in a foreign publication. Suffice it to say that the most brilliant act of war in my opinion would be to hand over both LRDE and GTRE to Pakistan as a peace offering. Once that is done, we can concentrate all our military capability against China, and not have to worry about the western at all; not as far as their air force is concerned :-D
 
I am a little reluctant to get into this. Some information is still classified; most is, actually, and I don't want to play chicken in a foreign publication. Suffice it to say that the most brilliant act of war in my opinion would be to hand over both LRDE and GTRE to Pakistan as a peace offering. Once that is done, we can concentrate all our military capability against China, and not have to worry about the western at all; not as far as their air force is concerned :-D
could you tell me what is LRDE and GTRE?
 
LRDE : Electronics and Radar Development Establishment. And yeah it starts with L so as to differentiate "Electrical" and "Electronic", the latter is abbreviated with the first letter of its Latin root (lektra).

GTRE : Gas Turbine Research Establishment.

Both of them are DRDO laboratories. First one is meant for Radars and second one is meant for gas turbines.
 
@ joe. i got it LRDE is drdo lab for radar research and GTRE gas turbine research establishment..and you were just kidding right ?
*though i googled it thanks for angledemon for the post.
 
@ joe. i got it LRDE is drdo lab for radar research and GTRE gas turbine research establishment..and you were just kidding right ?
*though i googled it thanks for angledemon for the post.

eLectronic Research and Devt. Establishment, yes, that's correct, and GTRE too.

I was kidding that particular moment. Thinking too long about GTRE (LRDE has done some outstanding work at times) makes me think seriously about that proposition.
 
thats 'Cranked arrow' - similar to a compound delta, but with the trailing edge also kinked inwards. Trialled experimentally on the General Dynamics F-16XL.

http://dc306.*******.com/img/s8-jwhsT/0.6235182629976099/gra6.PNG


I know! That is why I posted the pics so that the "cranked" part can be highlighted.

Apart from the obvious difference in the trailing edge, the Tejas wing has much more commonality with the F 16XL or the Viggen than Mirage 2000 AFA the working philosophy is concerned.


saab_37_viggen.jpg
 
I know! That is why I posted the pics so that the "cranked" part can be highlighted.

Apart from the obvious difference in the trailing edge, the Tejas wing has much more commonality with the F 16XL or the Viggen than Mirage 2000 AFA the working philosophy is concerned.


saab_37_viggen.jpg

the viggen was a step ahead of simple tailess delt -- it had coumpound delta plus a seperate fixed canard above the level of the main wing... after the viggen, even the canards became moveable in subsequent models
 
Saab35Draken.jpg
saab draken is without canards and a better example while comparing e f16xl
F-16XL-51.jpg
 
the viggen was a step ahead of simple tailess delt -- it had coumpound delta plus a seperate fixed canard above the level of the main wing... after the viggen, even the canards became moveable in subsequent models


While I agree with the facts from your post; I'm getting a faint impression that you think that the LCA is a simple tailless delta. (bolstered by your statements from Combat Aircarft Design thread)

If you think so, please elaborate.


Adding canards LCA variant with canards was evaluated during early phase of designing. It was canceled as studies indicated no extra benefits from this config.
 
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