Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

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tsarkar
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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby tsarkar » 02 Apr 2020 14:45

nachiket wrote:
tsarkar wrote:The LCA was small and light because it was designed around the capabilities of GTX-35 Kaveri. Absolutely no other reason.

And the Kaveri was the best we could conceptualize and develop at that point of time.

It was most definitely not that simple. ADA was created in 1984 and the ASQR for the LCA was finalized by IAF in 1985. Kaveri development began later. Kaveri was designed for the LCA not the other way around. LCA requirement came out of IAF's long term re-equipment plan of 1981. They were looking for a 1-to-1 replacement for the Mig-21's. I do now have the source now but I remember reading long time ago about the necessity of the replacement to be able to fit into the Mig-21 sized shelters at our forward air bases. Other considerations included cost. In the 80's we could not have imagined replacing the hundreds of Mig-21's flying with a larger aircraft which would be more expensive to both buy and operate, even though that eventually happened to a large extent in the 2000's with the Su-30.


https://tkstales.wordpress.com/2012/04/ ... /#more-857

The details were received through mail next morning. It was contained in a few pages of print. It described the intention to build a single engine tail-less delta plan-form aircraft powered by an engine designed by the GTRE.

The engine design concept was always there from Day 1 and part of the overall concept. The rest of the thought process is described.

Whether Marut, LCA Mk1, LCA Mk1A, TEDBF, AMCA - the deciding factor on capabilities and consequently size always was and always will be the available engine.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Gyan » 02 Apr 2020 17:28

My Understanding of LCA

To follow up to my earlier discussions on LCA, I did lot of reading and also tried to understand the posts and articles of Indranil (courtesy lockdown).
I had always been perplexed with (aerodynamic) design choices of LCA and had no satisfactory answer. Though I hasten to add that all the articles of Indranil (& posts) are correct (even as per my understanding) but they are written by an expert and hence does not address, in detail, some questions which layperson like me finds perplexing.

So there goes nothing.

LCA design made 3 major choices, which have always been perplexing and rather debated, being:-

Delta Wingform vs Conventional Swept wing
Fly by Wire vs Conventional Controls
Use of Composites

The more I study the issue, the more I realise that these choices were forced on DRDO-ADA and were not really a matter of free option. People offering simplistic solutions have not understood the problems/choices facing ADA.

This discussion is all the more pertinent because for LCA Mk-2 we are retaining the same Wingform.

To understand the issues facing ADA, we have to look at some real life comparisons:-

F-16 vs F-16XL
F-16 vs Mirage 2000
Mirage III vs Mirage F1 vs Mirage 2000

Now, why the delta wing?

Delta Wing planform controlled by FBW has a “longer range” than conventional swept wing inspite of the fact that Delta wing has “bigger” wing area. Now there goes one of the biggest myths facing LCA that its wing is big & hence draggy and “hence” LCA has a very short range of 350-500km. In fact even I thought that LCA wing with its big area was a huge draw back.

Fortunately the answer lies in some basic physics. Swept wing broadly acts like a normal airfoil but the lift in delta wing is generated by “vortex” generated over the wings. (Google the rest). It is something like, Indian Ballistic Missiles with blunt noses are more accurate than pointy missiles of Pakistan (gifted by China).

Due to these vortexes, Delta Wing inspite of a Bigger Area can generate lift with lesser drag and is more efficient in acceleration, transonic & supersonic regimes also compared to conventional swept back wing. Apart from having more storage area, better fatigue life, lower wing loading etc

But there is a catch, the trim drag of Delta wing tends to negate the benefits unless we use, guess….., FBW.
So for a “given” engine size Delta wing with FBW provides (substantially) more range and better speed, acceleration, etc. Now lets test this hypothesis through empirical data:-

F-16 vs delta wing of F-16XL, using the similar engine F-16XL has either double the payload or 40% more range

France went from Mirage F1 to Delta wing of Mirage 2000 to get better range, speed and acceleration

USA retained F-16 wingform but inspite of being an aircraft in similar category of Mirage 2000, it uses 20% to 40% more powerful engine which is 15%-20% more fuel efficient ie basically a generation ahead of M53 of Mirage 2000. Inspite that in lots of scenarios Mirage 2000 is better due to its Delta wing, like tau, response time, bank, roll rate, ITR, acceleration to supersonic regime etc. Though the sustained turn rate is relatively poor to way more powerful F-16.

USAF rejected F-16XL because they did not want to give up sustained turn rate (among other reasons, like they may have wanted twin engines) but Note:- they did not use F-16 but had to go in for much bigger aircraft ie F-15 with almost 3x the engine power of F-16 (relative to weight of aircraft)

Similarly Soviets had to use Mig-29 which is again twin engine and short ranged (compared to Mirage 2000) as it has neither FBW or Delta. Their Mig-23 was a dead end.

Coming back to LCA. LCA has a very advanced engine GE F404 and FBW with excellent fuel efficiency, FBW and Delta wing. Hence, My guess is that the narrative about its short range is incorrect. Some (old) discussions on BRF which gave Relative Range of Mig-21 as 400km, LCA-500km, Mirage 2000 as 700km and F-16 as 900km are also incorrect. Perhaps they estimated the range using conventional comparison of frontal area & surface area. As aforesaid, the lift and drag on Delta plan forms is completely different and not directly comparable to swept back wing on linear basis.

My best guess is that range of Mirage 2000 & LCA MK1 is better or more than F-16 A-D, (without conformal wing tanks). Or to put it differently Israel carried out the famous Iraqi Osirak Raid at 1100km range in lo-lo-hi mode using F-16s. Both Mirage 2000 and LCA would be able to do that with weapon payload similar to F-16.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby nash » 02 Apr 2020 20:45

https://twitter.com/hvtiaf/status/1245702590706278401?s=19

LRDE AESA Uttam has a silent launch mode.


What is silent launch mode ?

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby sankum » 02 Apr 2020 20:51

Passive mode?

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Karan M » 02 Apr 2020 20:55

Likely LPI track while scan.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby suryag » 02 Apr 2020 21:50

Gyan ji good writeup and frankly if you could rewrite it, it could be like a 101 lesson for a lot of newbies who cant understand/appreciate the technical reasonings in IR/JS articles(IR/JS sir kindly accept my advance apologies). In fact, you could turn your writeup into a crash course/charulata guide(new gen engineers from TN know what am referring to) :)

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby maitya » 02 Apr 2020 22:32

Gyan wrote:My Understanding of LCA

To follow up to my earlier discussions on LCA, I did lot of reading and also tried to understand the posts and articles of Indranil (courtesy lockdown).
I had always been perplexed with (aerodynamic) design choices of LCA and had no satisfactory answer. Though I hasten to add that all the articles of Indranil (& posts) are correct (even as per my understanding) but they are written by an expert and hence does not address, in detail, some questions which layperson like me finds perplexing.

So there goes nothing.
<snip>

Gyanji, since you have come thus far, I'd urge you go a little further and explore slightly more.

Pls note
i) LCA wings are not pure delta - but they are compound delta (aka there are two different sweep angles in it) - why so?
ii) The two different sweep angles create a kink (or a corner, if you will) in the in LCA wing - is there some advantage due to it?
iii) Vortex does help in lift, but how much and for how long?
iv) How does LCA design, despite having a delta planform, have so much superior STR values compared another classical delta designs like MiG-21 (or M2K, there I must have already offended some resident Francophile here)?
(do note deltas will have inferior STR but superior ITR than "conventional rectangular" planform)

... questions and more questions ...

You may want to refer some of mine and Indranil's very old posts (circa 2015 etc) wrt these aspects, that can help - both in layman terms, as always ofcourse.

Suryagji you may also refer to them ...

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby suryag » 02 Apr 2020 22:52

Sir am an aerodynamics expert :) because of you all, however, creating uncomplicated writeups(in Tamil they say how does a donkey know the smell of camphor and am calling myself a donkey here) helps beginners appreciate it.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Gyan » 02 Apr 2020 23:42

Thx, for heads up guys. I am working on making the write up better and addressing some issues indicated by Maitya
:)

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby ks_sachin » 03 Apr 2020 04:48

Gyan wrote:Thx, for heads up guys. I am working on making the write up better and addressing some issues indicated by Maitya
:)

Gyan,

Good effort for the benefit of all the aerodynamic newbies.

Could I request you do a similar exercise for the INSAS as well? People need to understand the design and the trade-off that made the weapon a reasonable failure.

Regards

S

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby ks_sachin » 03 Apr 2020 04:53

Gyan you have spoken about the F16 and the F15 and then the Mig 29 and Mig 23.
Maybe it would be interesting to unpack the design philosophies between both the comparisons but also the change in the operational scenario vis-a-vis adversary aircraft that made the Russian go the way of the Mig29.
What I am saying is that the design is based on the physics the design trade-offs are based on the operational requirements.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby vickyiyer » 03 Apr 2020 08:34

I came across an excellent video explaining the delta wing. In case you have not already seen it, please have a look.

https://www.youtube.com/watch?v=pquk8xo ... ihBDtM1Y5N

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby tsarkar » 03 Apr 2020 12:58

nash wrote:
https://twitter.com/hvtiaf/status/1245702590706278401?s=19

LRDE AESA Uttam has a silent launch mode.


What is silent launch mode ?


A passive picture is built up using ESM and data from other sensors like ground based radars and/or AEW&C. When a good firing solution is ready from this picture, missile is fired and guided by datalink until the missile goes active. The aircraft radar does not actively paint the target to get a firing solution.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby tsarkar » 03 Apr 2020 13:23

tsarkar wrote:Whether Marut, LCA Mk1, LCA Mk1A, TEDBF, AMCA - the deciding factor on capabilities and consequently size always was and always will be the available engine.


To add to my earlier post, the most basic fighter engine is GE F-404 that powers lightest possible fighters like Tejas, Gripen and trainers like K-50 and T-7. In its class are the Russian RD-33 powering the JF-17. The best the French can come up with is M88 that has same performance as GE F-404.

Its evolution is the F-414 and the EJ-200 that is the best the Rolls Royce (UK) and MTU (Germany) came up with.

The next higher engine class is the Al-31, P&W F-100 and GE-110. Please note that even leaders like P&W were struggling with the TF-30 and F-100.

https://en.wikipedia.org/wiki/Pratt_%26 ... formance_2
Due to the advanced nature of engine and aircraft, numerous problems were encountered in its early days of service including high wear, stalling[3] and "hard" afterburner starts. These "hard" starts could be caused by failure of the afterburner to start or by extinguishing after start, in either case the large jets of jet fuel were lit by the engine exhaust resulting in high pressure waves causing the engine to stall.


To summarize, the Europeans (France, UK, Germany) dont have an engine beyond F-404/414 levels.

Only Russia with Al-31 has an engine comparable to F-100/F-110 which is the next level

China like India tried but couldnt develop powerplants in either RD-33 or Al-31 class. We can ignore internet propaganda.

Coming back to Tejas, its engine design specifications was kept at the bare minimum level required to power a fighter. The Kaveri design specs were at GE F-404 and RD-33 levels. And consequently LCA Tejas specifications were around Kaveri & GE F-404 capabilities.

When those with headstart over India cannot develop engines of a higher class, it sheer fantasy to think we could have developed an engine with specs better than Kaveri.

And to think we could have had a fighter larger and more capable than Tejas at that point of time when engine technology was unavailable is utter wet dreams.

The size and capabilities of Tejas was defined by the available power plant. No other reason like MiG-21 sized hangers/HAS etc. Period.

Today a more capable engine (GE F-414) is available and we're designing larger and more capable MWF/Mk2, TEDBF and AMCA around it.

But in 80's, designing a "large" (and more capable) fighter was utterly impossible due to lack of available powerplant.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby VickyAvinash » 03 Apr 2020 16:45

tsarkar wrote:
tsarkar wrote:
The size and capabilities of Tejas was defined by the available power plant. No other reason like MiG-21 sized hangers/HAS etc. Period.

Today a more capable engine (GE F-414) is available and we're designing larger and more capable MWF/Mk2, TEDBF and AMCA around it.

But in 80's, designing a "large" (and more capable) fighter was utterly impossible due to lack of available powerplant.


tsarkarji, pls forgive my ignorance, but, couldn't twin engine instead of single engine solve this issue to a large extent. And the moment it was a twin engine, it couldn't have fitted into those hangers, but still could provide higher total thrust and larger payloads. So from this perspective it seems that the factors other than the powerplant capability were deciding factors for the form factor that LCA has today.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby chola » 03 Apr 2020 18:01

tsarkar wrote:China like India tried but couldnt develop powerplants in either RD-33 or Al-31 class. We can ignore internet propaganda.


Tsarkar ji, we can argue whether stealing and RE constitute development but the reality is they do have a domestic engine in the AL-31 class that powers hundreds of their frontline aircraft including their latest J-20, J-16 and J-10C. That's the WS-10.

Their RD-33 class is the WS-13 which was tested on the JF-17 but rejected by the Pakis.

We can say their next gen for medium and heavy classes are propaganda because they are not powering aircraft at the moment but they do have names and are live programs so we know at the very least they are working on them.

Simply ignoring this supply of engines is a pretty big hole in any thorough analysis, IMO. They spit out more fighters with WS-10s on a yearly basis than the UK and France combined.

And there is an added incentive for us to look at their WS-10 program. This thing developed in parallel with the Kaveri and in fact was tested at Gromov by the Russians at around the same time. I think a honest assessment on how the WS-10 got to the point where it is now powering three types of frontline fighters (could include a fourth if counting J-15 prototypes) while the Kaveri remains in the lab would do us good.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby tsarkar » 03 Apr 2020 20:55

VickyAvinash wrote:
tsarkar wrote:


tsarkarji, pls forgive my ignorance, but, couldn't twin engine instead of single engine solve this issue to a large extent. And the moment it was a twin engine, it couldn't have fitted into those hangers, but still could provide higher total thrust and larger payloads. So from this perspective it seems that the factors other than the powerplant capability were deciding factors for the form factor that LCA has today.


Very good thinking. However twin engines require more fuel load hence more space and more structural strengthening of fuselage, wings and landing gear. There are issues to solve like flight control in asymmetric thrust regimes or single engine failure. That would have made CLAW development more complex.

To keep development as simple and least risky as possible in terms of structure and control laws, a single engine design was chosen.

There are capex issues of two engines and opex issues of more fuel consumption as well.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby tsarkar » 03 Apr 2020 21:04

Chola Ji,

OT here,
I remember a report of Pakistanis refusing J-10 suggesting XX number of “improvements” that were defect rectifications. They refused Chinese engines on JF-17. When beggers like Pakistan refuse aid weapons, it reflects the quality of that stuff.

PAC Kamra started as F-6 Rebuild Factory as both airframes and engines had very low airframe life.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby chola » 03 Apr 2020 22:32

tsarkar wrote:Chola Ji,

OT here,
I remember a report of Pakistanis refusing J-10 suggesting XX number of “improvements” that were defect rectifications. They refused Chinese engines on JF-17. When beggers like Pakistan refuse aid weapons, it reflects the quality of that stuff.

PAC Kamra started as F-6 Rebuild Factory as both airframes and engines had very low airframe life.


Tsarkar ji, they rejected the J-10 for the JF-17 and because the Ruskies were so helpful as to provide the RD-93 then they had the option to take the better engine from one of the four established engine producing nations.

But quality not withstanding the chinis do have a pretty thriving engine industry right now based on a heavy class engine.

Now, today we too have some experience with engines of that class. HAL builds 70% of the AL-31FP for MKI. What was not available during the time when LCA was first envisioned is available today. A true medium class fighter based on a single heavyweight engine like the F-Sola is possible if we make use of what we learned building the AL-31FP, IMO.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby nachiket » 03 Apr 2020 23:34

tsarkar wrote:To add to my earlier post, the most basic fighter engine is GE F-404 that powers lightest possible fighters like Tejas, Gripen and trainers like K-50 and T-7. In its class are the Russian RD-33 powering the JF-17. The best the French can come up with is M88 that has same performance as GE F-404.

Its evolution is the F-414 and the EJ-200 that is the best the Rolls Royce (UK) and MTU (Germany) came up with.

The next higher engine class is the Al-31, P&W F-100 and GE-110. Please note that even leaders like P&W were struggling with the TF-30 and F-100.

To summarize, the Europeans (France, UK, Germany) dont have an engine beyond F-404/414 levels.

You are comparing engines in different classes and saying one is better than the other because it generates higher thrust. That is simply incorrect. Before the F404 sized M-88, the French had the M53-P2 on the Mirage-2000 which generated significantly more thrust than the M-88. Does that mean the French went backwards in capability? No! Every engine is designed within the size and weight constraints of its intended applications. The M-88 was designed to be smaller because you cannot fit two M53 or F100 sized engines into the Rafale. The aircraft would have to be bigger to accommodate that. The French didn't want it bigger. Otherwise they would have gone with the much larger Mirage-4000 which had already flown with 2 M53 engines.

Only Russia with Al-31 has an engine comparable to F-100/F-110 which is the next level

China like India tried but couldnt develop powerplants in either RD-33 or Al-31 class. We can ignore internet propaganda.

AL-31 is not *better* than the M-88 or F414. In fact those engines are more modern with a better MTBF. AL-31 is simply larger. If you scale up an engine design, it will generate more thrust. That does not automatically make it better. It might actually make it useless if the engine gets too big for the intended aircraft. GTRE while designing the Kaveri did have size and weight restrictions because the IAF wasn't looking for a J-10 sized aircraft (which the LCA would have to be to accommodate an AL-31 or F100 sized engine). It was looking for a light Mig-21 replacement. If the Kaveri design is scaled up to make a bigger engine, it can generate more thrust. That won't make it a better engine, just a larger one.

When those with headstart over India cannot develop engines of a higher class, it sheer fantasy to think we could have developed an engine with specs better than Kaveri.

I have never said we could design a higher specced engine than the Kaveri. We could barely build one with the Kaveri's specs. My issue is with the "specs" you choose to compare engines. We could have designed a larger engine, and it would have generated more thrust. But that does not make it a *better* engine in and of itself. In fact relaxing the size and weight limitations can make designing an engine easier (as is the case with a lot of other engineering problems). GTRE did not have a free hand in designing the engine (no engine manufacturer does). The size, weight and internal space of the intended application always has to be kept in mind. When the intended application is being designed in parallel like the LCA you have some leeway, but the engine is not the only consideration for the design of an aircraft. Its intended purpose is equally if not more important. So the engine size/weight/fuel consumption cannot grow beyond a point.


Ask yourself why the Swedes built the single F404 powered Gripen? They were importing the engine anyway and the PW-F100 and GE-F110 were already available. By your logic they could have just enlarged the original Gripen design to use those engines because they are "better". There are always other considerations.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Kartik » 04 Apr 2020 00:03

nachiket wrote:You are comparing engines in different classes and saying one is better than the other because it generates higher thrust. That is simply incorrect. Before the F404 sized M-88, the French had the M53-P2 on the Mirage-2000 which generated significantly more thrust than the M-88. Does that mean the French went backwards in capability? No! Every engine is designed within the size and weight constraints of its intended applications. The M-88 was designed to be smaller because you cannot fit two M53 or F100 sized engines into the Rafale. The aircraft would have to be bigger to accommodate that. The French didn't want it bigger. Otherwise they would have gone with the much larger Mirage-4000 which had already flown with 2 M53 engines.


+1.

the M-88 was designed for the Rafale size and design requirements, not the other way around. In fact, the prototype Rafale that flew with the F-404 was slightly larger than the later prototypes and production Rafales that flew with M-88. And as you rightly said, the M53-P2 generates 98 kN, so if they wanted, they could have developed a more modern M53-P2, a F-414 equivalent in thrust. But 2 X M53-P2s would have made it a larger and heavier jet, like the Mirage-4000.

nachiket wrote:AL-31 is not *better* than the M-88 or F414. In fact those engines are more modern with a better MTBF. AL-31 is simply larger. If you scale up an engine design, it will generate more thrust. That does not automatically make it better. It might actually make it useless if the engine gets too big for the intended aircraft. GTRE while designing the Kaveri did have size and weight restrictions because the IAF wasn't looking for a J-10 sized aircraft (which the LCA would have to be to accommodate an AL-31 or F100 sized engine). It was looking for a light Mig-21 replacement. If the Kaveri design is scaled up to make a bigger engine, it can generate more thrust. That won't make it a better engine, just a larger one.


+1 again.

nachiket wrote:I have never said we could design a higher specced engine than the Kaveri. We could barely build one with the Kaveri's specs. My issue is with the "specs" you choose to compare engines. We could have designed a larger engine, and it would have generated more thrust. But that does not make it a *better* engine in and of itself. In fact relaxing the size and weight limitations can make designing an engine easier (as is the case with a lot of other engineering problems). GTRE did not have a free hand in designing the engine (no engine manufacturer does). The size, weight and internal space of the intended application always has to be kept in mind. When the intended application is being designed in parallel like the LCA you have some leeway, but the engine is not the only consideration for the design of an aircraft. Its intended purpose is equally if not more important. So the engine size/weight/fuel consumption cannot grow beyond a point.

As yourself why the Swedes built the single F404 powered Gripen? They were importing the engine anyway and the PW-F100 and GE-F110 were already available. By your logic they could have just enlarged the original Gripen design to use those engines because they are "better". There are always other considerations.


+1

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Kartik » 06 Apr 2020 10:38

Super graphics from Kuntal in this video. If his rendering is even 80% accurate, based off the drawings from HAL's tenders, then the MWF is going to be one of the best looking 4.5 gen fighters in the world. Perfectly proportioned, the kind that will make jingos drool. Truly wish that ADA folks get in touch with him to get their brochure images done by him.


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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Indranil » 06 Apr 2020 10:54

Excellent. The intake splitter plate will be slightly different. But everything else is pretty spot on.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby tsarkar » 06 Apr 2020 13:34

nachiket wrote:You are comparing engines in different classes and saying one is better than the other because it generates higher thrust.

Yes, I am discussing only thrust class and not technical superiority of engines for the purpose of this discussion.

Because ability to develop engine of a particular thrust class was "the" key constraint in LCA design and development.

nachiket wrote:AL-31 is not *better* than the M-88 or F414. In fact those engines are more modern with a better MTBF.


Again, the key constraint in LCA design development was "thrust". Not MTBF.

Who cares about MTBF when basic thrust isnt there?

Its like discussing a kid's 6th grade performance (MTBF) when he doesnt fulfill the criteria to pass 4th grade (Thrust) :D

nachiket wrote:We could have designed a larger engine, and it would have generated more thrust.

:rotfl:


nachiket wrote:In fact relaxing the size and weight limitations can make designing an engine easier (as is the case with a lot of other engineering problems).

No it doesnt because as you answered -
nachiket wrote:If you scale up an engine design, it will generate more thrust. That does not automatically make it better. It might actually make it useless if the engine gets too big for the intended aircraft.

Its not size, its factors like thrust to weight ratio that will make big engines useless.

The Chinese made aircraft like J-8 with two MiG-21 engines but its performance was pathetic other than colliding with USN P-8 ELINT aircraft. Size wasnt an issue. But TWR was.

Anyways I leave it here. Its the available engine that decides the aircraft design and performance parameters

The last aircraft to try to have an engine designed around it was the Marut and we know where it went.

tsarkar
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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby tsarkar » 06 Apr 2020 13:51

nachiket wrote:Ask yourself why the Swedes built the single F404 powered Gripen?

You ask yourself if India's design constraints were the same as Sweden's?

While Sweden may have had the choice of engine, India didnt.

nachiket wrote:the PW-F100 and GE-F110 were already available

Are you really sure Swedes had PW-F100 and GE-F110 available? The Swedes wanted to manufacture the engine as Volvo RM-12.

Read up CFM-56 development where US denied sharing GE engine technology and the core comes prebuilt from US. Other parts are assembled in France under US supervision.

https://en.wikipedia.org/wiki/CFM_Inter ... 6#Overview
Engines assembled in France were subject to the initially strict export agreement, which meant that GE's core was built in the U.S., then shipped to the Snecma plant in France where it was placed in a locked room into which even the President of Snecma was not allowed. The Snecma components (the fore and aft sections of the engine) were brought into the room, GE employees mounted them to the core, and then the assembled engine was taken out to be finished.


So where the US doesnt allow France, a NATO member, to license built core technologies from F-101/110 family, they would allow Sweden, a non NATO member, to license build the same engine :rotfl:

Maybe if you dig deeper, even the Swedes possibly had the same challenge as India did. Availability of engine.

And like India, when a better F-414 was available, they designed Gripen E/F

Kartik wrote:the M-88 was designed for the Rafale size and design requirements, not the other way around. In fact, the prototype Rafale that flew with the F-404 was slightly larger than the later prototypes and production Rafales that flew with M-88. And as you rightly said, the M53-P2 generates 98 kN, so if they wanted, they could have developed a more modern M53-P2, a F-414 equivalent in thrust. But 2 X M53-P2s would have made it a larger and heavier jet, like the Mirage-4000.


Love the way you folks complicate simple facts to suit your arguments. And put the cart before the horse.

A simple reason of not using M53 in Rafale was that technology had improved to M-88 level thrust with smaller size. If technology hadn't, they would be flying Mirage 4000.

No matter how much you twist logic, the Universal Truth is that its the available engine technology that decides aircraft design parameters.

Not the other way around of aircraft design parameters influencing engine development.

Any aircraft wanting an engine to be developed around its design suffered like the Marut.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Rakesh » 06 Apr 2020 18:34

Kartik wrote:Super graphics from Kuntal in this video. If his rendering is even 80% accurate, based off the drawings from HAL's tenders, then the MWF is going to be one of the best looking 4.5 gen fighters in the world. Perfectly proportioned, the kind that will make jingos drool. Truly wish that ADA folks get in touch with him to get their brochure images done by him.

That man is truly gifted. Amazing work.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Rakesh » 10 Apr 2020 04:20


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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Kartik » 10 Apr 2020 06:28

Just look at how good this guy Kuntal's CG is..MWF looks amazing!!

Image

Rakesh, perhaps this image ought to be on the first page of this thread?

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby nachiket » 10 Apr 2020 07:18

Is an IRST confirmed for Mk2? I see it in Kuntal's CG image.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby srai » 10 Apr 2020 09:22

Kartik wrote:Just look at how good this guy Kuntal's CG is..MWF looks amazing!!

...

Kartik, just the way you like it with dual AAM racks 8)

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Rakesh » 10 Apr 2020 19:11

Kartik wrote:Rakesh, perhaps this image ought to be on the first page of this thread?

Most definitely it should. I need his permission though. I need to get in touch with him.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby maitya » 10 Apr 2020 22:19

nachiket wrote:Is an IRST confirmed for Mk2? I see it in Kuntal's CG image.

Nothing confirmed etc, but that's the plan we are hearing, right? The second (and smaller) plug (the nose-plug) is to allow for IRST integration.

The jingo wet-dream of course, is we will have an indigenous OSF equiv - just like the dreams of having our own Mayavi being equivalent to Spectra.
After all, there is no cost associated with dreaming ... but then again, who'd have thought some 5-6 years back we will have an Uttam giving 2052 a run for their money.


On a related note, what I do not understand however is, why is it so difficult to develop a D-29 equivalent of RWJ for the Mk1As and just shoehorn it at the base of the tail fin, and be done with it - like this...
Integration (with 2052/Uttam et all) will be a challenge, but nothing insurmountable or anything.
And a 4-channel equiv (why do we need 6-channel etc for a platform of the size of LCA) of Dhruti can replace the analog R118 on the top of the tail fin etc.

In fact back in 2015 we heard Mayavi has been successfully integrated into PV1 and flight testing is on - no idea, what came out of it, as there's been no news since then. :(

Oh dreams ... and more dreams ... :P

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Kartik » 10 Apr 2020 23:56

nachiket wrote:Is an IRST confirmed for Mk2? I see it in Kuntal's CG image.


Yes it is. Was always shown in the ADA MWF model as well.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Kartik » 10 Apr 2020 23:57

srai wrote:
Kartik wrote:Just look at how good this guy Kuntal's CG is..MWF looks amazing!!

...

Kartik, just the way you like it with dual AAM racks 8)


YES! :D

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Kartik » 11 Apr 2020 00:02

maitya wrote:
nachiket wrote:Is an IRST confirmed for Mk2? I see it in Kuntal's CG image.

Nothing confirmed etc, but that's the plan we are hearing, right? The second (and smaller) plug (the nose-plug) is to allow for IRST integration.

The jingo wet-dream of course, is we will have an indigenous OSF equiv - just like the dreams of having our own Mayavi being equivalent to Spectra.


In 2018, the indigenous Long Range Dual Band IRST was approved by the Defence Minister, for the Su-30MKI upgrade.

link

Earlier this week, the Defence Acquisition Council (DAC), led by India’s defence minister, also approved the indigenous design and development of a long range dual band infrared imaging search and track system (IRST) for the Su-30 MKI. At least 100 units are to be procured.


Would make logical sense that the same indigenous LR DB IRST will find place on the MWF as well.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby ManuJ » 11 Apr 2020 01:27

Kartik wrote:Just look at how good this guy Kuntal's CG is..MWF looks amazing!!

Image

Rakesh, perhaps this image ought to be on the first page of this thread?


Awesome rendering!
Doesn't MWF have a retractable refueling probe though? This looks like the LCA Mk1 fixed probe.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Kartik » 11 Apr 2020 03:39

Yes it should. That's the only thing that needs correction.

Some more screengrabs from Kuntal's video. Pure MWF por*.


Image
Image
Image
Image
Image
Image
Image
Image

Praying daily that the IAF ditches the current Tejas paint scheme and goes with overall grey. It looks so good in an overall grey scheme, as can be seen in these images. At least for the Tejas Mk1A and MWF, the Mk1 is a gone case.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby nachiket » 11 Apr 2020 03:52

Kartik wrote:
srai wrote: Kartik, just the way you like it with dual AAM racks 8)


YES! :D

Also carries an Astra on each wingtip. That is probably an error though. The wingtip pylon would be limited to a CCM most likely.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Kartik » 11 Apr 2020 04:22

Yes, it should most likely carry CCMs on the wingtip pylons. The weight difference between ASRAAM and Astra is nearly 70 kg per missile.

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Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Postby Gyan » 11 Apr 2020 22:20

My Understanding of LCA Attempt-2

To follow up to my earlier discussions on LCA, I did some more reading and also tried to understand the posts and articles of Indranil, Nilesh Rane, Surya and Maitya (courtesy lockdown).

I had always been perplexed with (aerodynamic) design choices of LCA and had no satisfactory answer. Though I hasten to add that all the articles of Indranil, Nilesh, Maitya (& posts) are correct but they are written by an expert and hence does not address, in detail, some questions which layperson like me finds perplexing. That is to say that they are dealing with Algebra while we are struggling with Sita Kaun thi?

The primary grievance against LCA is that it is inadequate and small little aircraft with short radius of action 300km-500km. Just like a Mig-21 so why did we not go with upgraded Mig-21.

Second is that LCA has not achieved what F-16 and Mirage did 40 years ago, hence why did we not adopt the design philosophies of Mirage 2000/F-16 rather than trying to re-invent the wheel?

So there goes nothing.

LCA design made 3 major choices, which have always been perplexing and rather debated, being:-

1. Delta Wingform vs Conventional Swept wing
2. Fly by Wire vs Conventional Controls
3. Use of Composites

The more I study the issue, the more I realise that these choices were forced upon DRDO-ADA and were not really a matter of free option. People offering simplistic solutions have not understood the problems/choices facing ADA.

But before we discuss the design choices, let’s have a look at the Dilemmas of the Political leadership and IAF Brass. My understanding is as follows:-

1. We did not go for upgraded Mig-21 as Soviets would not have co-operated. Further enlarging the nose of Mig-21s to put in a better radar would have given us a completely different aircraft with range even shorter than Mig-21, if we had used Mig-21 technology base.

2. We did not reverse engineer or go in for design philosophy of F-16s or Mirage 2000 as we did not have the “Engine”! No one was offering us 100kn engine.

3. Unfortunately the experts, even ex-IAF pilots look at things in compartments. It is easy to say upgrade the Mig-21 as if Soviets were their FILs with Garlands in their hands. Additionally, Soviets fighter aircraft had shit kicked out of them in 1982 Yom Kippur Israel-Syria war and we had to prepare ourselves against Pak and China acting together (perhaps using Western Equipment). We also knew that next Gen Soviet aircraft to Mig-21 being Mig23 were no match for western equipment. Even Mig-29 until recently has been very short ranged & maintenance heavy aircraft. Only when RD33/93 became powerful enough in this decade, its able to carry enough fuel using TWO Engines.

4. Rajiv Gandhi wrangled the most modern engine at the time being GE F404 (75kn) from Ronald Reagan and we set upon the task of developing a fighter equal to F-16/Mirage 2000 around that engine as we had no other choice. Rajiv Gandhi Got us:-

1. World most modern (small) Engine GE F404 75kn - USA
2. FBW – USA Martin Mareitta
3. Design – BAE, Dassault - UK, France
4. Composites and Wings construction – Italy - Alenia, Germany
5. Radar – Ericssion Sweden

And now using these building blocks we had to develop an aircraft which would be equal to F-16/Mirage 2000 and will not get its ass kicked like Syria in Yom Kippur 1982 and Argentina in Falklands 1982.

Intention of Indian DRDO & IAF Brass :-

We always intended to develop an aircraft way more advanced than F-16/Mirage 2000 with “more range” We went about portraying it as little toy aircraft to avoid attracting attention during Cold War Era and subsequently to avoid getting the programmed derailed by competitors. Remember our polite non-threatening Dr. Abdul Kalam working on sounding rockets. The Aim to develop long range Ballistic Missiles was always his real intent.

My understanding is that LCA was intended to be 1000-1200km range aircraft, and even now its 800-900km range aircraft (due to weight gain)
In any case, the discussion is all the more pertinent because for LCA Mk-2 we are retaining the same Wingform with Canards.

To understand the design issues facing ADA (which was to develop a aircraft equivalent to F-16/Mirage 2000 while using GE F404 – 75kn engine), we have to look at some real life examples:-

F-16 vs F-16XL

F-16xl was a delta wing variant of F-16. Most of my assertions in this article are based on 300 Page NASA Study on F-16XL which is available on Internet for public. This is the most important comparison for the purpose of present article as it indicates what would happen to range and payload (and other aerodynamic features) of LCA if Delta wing is dropped for conventional swept wing to increase STR.

F-16 vs Mirage 2000

F-16 has way better engine 1 generation ahead of Mirage 2000, which is 20%-30% more powerful while being 15%-20% more fuel efficient. F-16 has more conventional swept wing vs. Mirage 2000 tailless delta wing.

(Strictly speaking F-16 is not conventional swept wing, uses leading wing root edges but we are going to keep it simple.)

Mirage III vs Mirage F1 vs Mirage 2000 vs Rafale

France developed a hugely successful tailless Delta wing Mirage III, went to conventional swept wing with Mirage F1 and then came back to Mirage 2000 again with FBW controlled tailess delta wing and moved ahead to Close coupled canard Delta Wing Rafale

Now, why the delta wing for LCA?

Did we choose a bad design and are Sticking with a bad design? Is DRDO incompetent or Lazy? Should I pick up my Phone and educate ADA-DRDO?

Answer:-LCA has Delta Wing planform controlled by FBW because it has a “longer range” than conventional swept wing inspite of the fact that Delta wing has “bigger” wing area for a “given” engine power.

Now there goes one of the biggest myths facing LCA that its wing is big & hence its draggy and “hence” LCA has a very short range of 350-500km. In fact even I thought that LCA wing with its big area was a huge draw back.

As per NASA studies on F-16XL, FBW Delta wing has 40% more range (compared to F-16, inspite of being big and (allegedly) draggy).

Refer:-

https://www.nasa.gov/sites/default/file ... flight.pdf

Fortunately the answer lies in some basic physics. Swept wing broadly acts like a normal airfoil but the lift in delta wing is generated by “vortex” generated over the wings. (Google the rest). It is counter-intuitive and is something like, Indian Ballistic Missiles with blunt noses are more accurate than pointy missiles of Pakistan (gifted by China).

Refer:-

https://www.youtube.com/watch?v=pquk8xoFJDU&t=607s
http://www.mirage-jet.com/COMPAR_1/compar_1.htm

Due to these vortexes, Delta Wing inspite of a Bigger Area can generate lift with lesser drag and is more efficient in not only cruise but also acceleration, transonic & supersonic regimes compared to conventional swept back wing (or even advanced swept back wing of F-16). Apart from having better ITR, more storage area, better fatigue life, lower wing loading, easier to manufacture etc.

Hence Bander FC-17 with its weak ass thirsty engine, limited FBW, swept back wing and aluminium body may have only 40% to 60% range of LCA (not withstanding Pak fanboy posts)

But Delta Wing does have cons like longer take off & landing runs, lower STR etc.

But why waste time over FBW? Could we not have gone for conventional controls with stable aircraft? Should I call up ADA and tell them about their stupidity as I just thought about it? Even some ex-IAF pilots say so. Why did we waste 5-15 years struggling with FBW? ADA Guys are fools!! I am more intelligent!!!

But there is a catch, about adopting Delta Wing. That pesky thing called Physics again! But anyway, unfortunately the trim drag of Delta wing tends to negate the benefits unless we use, guess….., FBW.

FBW by automatic computerised movement of control surfaces can massively reduce the trim drag penalty of Delta Wing.

https://youtu.be/pquk8xoFJDU

Therefore if we use Delta wing without FBW then it has range shorter than swept back wing, due to trim drag. For Eg, LCA range would fall by 40%-60% and it may have a range of only 300km-500km equal to Mig-21 rather than 800-1200km equal to F-16s/Mirage 2000.

So for a “GIVEN” engine size Delta wing with FBW provides (substantially) more range and better speed, acceleration, etc.
Which means that FBW is not a matter of choice and is forced upon the designers if they want good range.

Now lets test this hypothesis through empirical data:-

F-16 vs delta wing of F-16XL, using similar engine F-16XL has either double the payload or 40% more range, (says NASA)

Another Eg. French Mirage III was delta wing without FBW. So France went to Mirage F1 conventional swept wing for better range (and other benefits off course). Thereafter when it was able to develop FBW it went back to Delta wing which had even better range. Hence, France went from Mirage F1 to Delta wing of Mirage 2000 to get better range, speed and acceleration. Conclusion LCA has 40%-60% better range than Chinese Bandar FC-17

These Bloody Yinodoos, they are surreptitious scoundrels! Cheating the world media, world powers, dalal lobby; all the while developing ballistic missiles while talking about sounding rockets.

We can test this hypothesis further. Mig-21, Mig-23Mig-29s, (earlier versions) all are very short ranged. USA had to use two engine heavies like F-15s and Soviets Su-27s with 300%-400% more power than LCA to get range and STR. Even present versions of Mig-29s which are really replacements of Mig-21s are giant beasts.

Hence, without FBW, without Delta wing, without composite body, the penalties are very heavy,. The only alternative is 2 “bigger engines” and as aforesaid we DID NOT have a Bigger engine.

We had a underpowered Marut and now underpowered Jaguar. Wonder why Jaguar was not used in Srilanka, Kargill and Balakot Revenge Strike??? It has everything the Desk Jockeys want. No FBW, No Delta and No Composites, not even a Radar, so did we want LCA to be like that?

Even though USAF rejected F-16XL because they did not want to give up sustained turn rate (among other reasons, like they may have wanted twin engines) but Note:- they did not use F-16 but had to go in for much bigger aircraft ie F-15 with almost 3x the engine power of F-16 (relative to the weight of aircraft)

Similarly (as aforesaid) Soviets had to use Mig-29 which is again is twin engine and still short ranged (compared to Mirage 2000) as it has neither FBW or Delta (nor any composites). Their Mig-23 was a dead end.

Coming back to LCA. LCA has a very advanced engine GE F404 and FBW with excellent fuel efficiency, FBW and Delta wing.

Hence, My guess is that the narrative about its/LCA short range is incorrect. Some (old) discussions on BRF which gave Relative Range of Mig-21 as 400km, LCA-500km, Mirage 2000 as 700km and F-16 as 900km are also incorrect. Perhaps they estimated the range using conventional comparison of frontal area & surface area. As aforesaid, the lift and drag on Delta plan forms is completely different and not directly comparable to swept back wing on linear basis.

My best guess is that range of Mirage 2000 & LCA MK1 is better or more than F-16 A-D, (without conformal wing tanks). Or to put it differently Israel carried out the famous Iraqi Osirak Raid at 1100km range in lo-lo-hi mode using F-16s. Both Mirage 2000 and LCA would be able to do that with weapon payload similar to F-16.

Arguing the issue from another angle:-

India did not have much choice. One suggestion was to simply develop Mig-21 further. It would not have led to much benefit and would have faced Soviet Resistance. We must remember that upgraded Mig-21s, Mig-23s, Mig-29s all, are no match to overall capabilities of Mirge 2000 and F-16s. Not to forget that we were already manufacturing Mig-21s and intended to license Manufacture Mirage 2000.

We tried to upgrade the design of Marut & did other sort of paper designs but were running into all sort of difficulties.

We were developing Kaveri engine (which was at initial stages) and with great difficulty Rajiv Gandhi wrangled GE F404. Was anyone offering bigger or better engine? Soviets were NOT offering RD-33 or Al-31!

Therefore DRDO had to design an aircraft around GE F404 (& potential Kaveri) which would successfully compete against Mirage 2000 and F-16s of the world. Hence there was no option but to adopt Delta Wing and FBW.

Off course there was a follow on two engined aircraft planned (MCA) but that’s another story.

What about the penalties of using Delta wing ? After all USA does not use it “nowdays” and neither does Russia.

Yes, there are penalties of using Delta Wing. Lets again look at F-16 vs Mirage 2000 for this.

USA retained F-16 wingform but inspite of being an aircraft in similar category of Mirage 2000, it uses 20% to 40% more powerful engine which is 15%-20% more fuel efficient ie basically a generation ahead of M53 of Mirage 2000.

Hence if we do not intend to use FBW controlled Delta wing we need a bigger engine and preferably two bigger engines which are also more fuel efficient because………..? they are bigger! Get it? (Which as aforesaid we don’t have, even today.)

Now, Inspite of F-16 bigger and more powerful and more efficient engine, still in lots of scenarios Mirage 2000 is better due to its Delta wing, like tau, response time, bank, roll rate, ITR, acceleration to supersonic regime etc.

Though the sustained turn rate is slightly poor to way more powerful F-16. Take off and landing distance is also more than F-16. Same problems are there in LCA also. As per some/lots of experts this minor difference in STR is not material compared to other benefits. Look at F-18 being used by USN, it is supposed to a pig.

http://www.mirage-jet.com/COMPAR_1/compar_1.htm

Further in any case, LCA was always intended to be followed up by 2 engine aircraft. The preliminary designs started circulating since 1990s as MCA. This would have been the follow up aircraft intended to address any deficiency in LCA.

Now coming to composites, Its incorrect to say that we had no exposure to composites.

We were already started absorbing composite technology with ALH, Dornier aircraft etc. The use of composites was essential as we had a punny engine with a big wing area, and an undeveloped aviation sector. It was an insurance against excessive weight gain, while maintaining competitive performance aganst F-16s, Mirage 2000, Mig-29s of the world.

I am not saying that LCA programme is perfect or that delay is justified but that the design choices were forced upto DRDO ADA and there was no easy way out. It was not a simple to say:-

Drop FBW, which would have led to 25%-50% range fall
Use aluminium body, which would have led to weight gain and 20% range fall
Using conventional swept wing, with aluminium body and conventional controls would have led to Mig-21 type range with bigger nose radar i.e. 20%-40% range fall

People tend to forget that the only low tech equivalent aircraft is FC-17 of China and we have no real world knowledge of its performance. But based on discussion above it will have less than half the range of LCA and very poor performance.

We (including myself) have always found LCA inadequate primarily due to short range. Seems like a punny aircraft. But based on my reading of NASA reports on F-16XL, I would like to say that LCA has range better or equal to Mirage 2000, F-16 (without conformal fuel tanks) and better than Gripen, Jaguar, early version of Mig-29 and double or triple the range of FC-17. Import dalals have been trying to create doubts in our minds by negative leaks and articles.

LCA with ferry range of 2100km in itself indicates a combat radius of 700-900km and these are early days when everything is done safely.

Compound Delta Wing

Now another minor (?) Gripe is that we use an over-complicated compound delta wing. Why did we not a simple pure delta like Mirage 2000. The answer is equally simple we were trying to decrease the limitations of Mirage 2000 and achieve a better performance.

Low swept Angle of wing (adjoining the fuselage) is intended improve low speed handling, angle of attack and to improve STR. Perhaps that is why LCA has a better STR than Mirage 2000. LCA also has a very small turning radius.

Compound Delta is well studied wing form used in Viggen and F-16XL.

Maitya & Indranil Excellent discussion is at :-

viewtopic.php?f=3&t=6663&start=3200#p1774291
viewtopic.php?f=16&t=6663&start=3240#p1775430
http://delhidefencereview.com/2019/02/2 ... er-part-i/

LCA MK-2 and why does it use Canards

Now if all of above is right and correct, and everyone lived happily thereafter, then what about LCA Mark-2. Why does it use Canards and why did we not use canards earlier?

LCA Mk-2 can use Canards to get better STR, shorter take off and landing distance because it has access to bigger engine GE F414, which generates almost 25% more power than GE F404

So the Canards will add some penalty of weight & drag but with bigger engine, more fuel we end up getting everything like better STR, shorter take off and landing distance alongwith more fuel, hence more range, more payload as LCA MK-2 is a bigger aircraft Rafale, Eurofighter also used Canards as they have 2 engines while Gripen is a short ranged pig

LCA Mk2 will be equal to or better than F-16/21 even with conformal fuel tanks and way ahead of upgraded Mig-29s, Gripen E/NG.

Naval LCA MKI, MK-2 will not be better than Mig-29Ks as NLCA is still evolving design which is heavy and underpowered compared to Mig-29Ks. Though there is serious doubt about the availability of Mig-29Ks on Naval deck.

http://delhidefencereview.com/2019/02/2 ... t-fighter/
http://www.indiandefencereview.com/news ... d-options/

Future

In AMCA we have gone for a different wingform as we wanted a stealthy aircraft but we are using two engines more powerful than Single Engine of LCA MK1.

Navy which wanted to longer range has (for now) stuck with LCA MK-2 wing form and Canards. Navy may want TDEF/ORCA to match or better Mig-29k reported 1200 km combat range with 6000 kg payload


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