LCA News and Discussions

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Kartik
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LCA News and Discussions

Postby Kartik » 10 May 2012 01:51

Last incarnation of this thread, viewtopic.php?f=3&t=5807
=============================================================
Background articles on HAL Tejas (LCA)

_____________________________________________
Excellent overview of Tejas, from the developer itself.
http://www.tejas.gov.in/
_____________________________________________


1.http://en.wikipedia.org/wiki/HAL_Tejas

2.Remembrance of Aeronautical Matters Past (Brief history of India's Aerospace Industry)
http://vayuaerospace.in/Selected_articl ... brance.htm

3.All the articles at BR page on LCA.
http://www.bharat-rakshak.com/IAF/Aircr ... Links.html

4.http://www.acig.org/exclusives/LCA/ACIG ... Tejas.html

5.http://www.lca-tejas.org/

6.Good background on project, a bit dated.
http://www.geocities.com/spacetransport ... t-lca.html

7. Harry's Radiance of the Tejas article
http://www.bharat-rakshak.com/IAF/downl ... diance.pdf

8. ADA overview on LCA, including interviews of test pilots, a peak inside the R&D labs and rare footage.



Newbies beware ! If you make ignorant remarks, you could be grilled by gurus
to test your LCA knowledge from these pages !
And, if you come out deficient..............(you would do better not to find out !)
:twisted:

Please stay on topic.

That means :
a> No comparison with aircraft A,B or C.
b> No half-baked suggestions to improve LCA like "add a laser gun"/"merge DRDO with ISRO " etc etc.
c> NO whining.

======================================================


Since the last LCA thread was locked after crossing the 101 page mark, created a new thread for it.

Wanted to thank PratikDas for that FaceBook page link that has pics of NP-1 that are not around anywhere else.

Strange as to why the official Tejas website has no updates on NP-1, no pics, no videos, no mention of the first flight at all !
Last edited by Rahul M on 10 May 2012 16:27, edited 1 time in total.
Reason: Whoever starts a new thread, please remember to add the background sources from first post and a link to the last thread.

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Re: LCA News and Discussions

Postby SaiK » 10 May 2012 04:19

Per tarmak, HAL has issues in sharing photos.

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Re: LCA News and Discussions

Postby SidSom » 10 May 2012 09:02

what I find interesting is that even the chase plane didn't retract its LG. Is that always the case that the chase flies the exact same profile as the lead plane.?

Beautiful pics..... oasis in the desert :)

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Re: LCA News and Discussions

Postby Jaeger » 10 May 2012 11:55

Is it just me or is the Navy's blue-grey paint job MUCH better-looking overall than the IAF Tejas' 2-colour scheme? In fact I prefer it to the std IAF Tipnis grey as well as the Navy's 'ghost' grey on the Harriers as well as the lighter Grey on the 29Ks... the blue-grey mix seems to be a lot 'richer' (TFTA?) than the Tippy and other greys...

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Re: LCA News and Discussions

Postby chackojoseph » 10 May 2012 12:04

SidSom wrote:what I find interesting is that even the chase plane didn't retract its LG. Is that always the case that the chase flies the exact same profile as the lead plane.?

Beautiful pics..... oasis in the desert :)


In first flight it is. If you remember the LCA first flight, m2K also flew the same profile. So both were cross checking if the air speed and other parameters were the same. So, in case if they are landing, the air speed indicator or other parameter is faulty, the the chase plane can tell the actual reading to enable the prototype to land.

Also, ADA can study the actually differences in both versions during same flight profile.

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Re: LCA News and Discussions

Postby Lalmohan » 10 May 2012 12:43

also, easier to maintain the same airspeed with the same drag configuration

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Re: LCA News and Discussions

Postby maitya » 10 May 2012 16:16

Cool a new thread ... so can post again. 8)

In the now locked previous thread LCA News and Discussions, Cainji asked the following important question that still needs answering viz.
Cain Marko wrote:<snip>
Define fuel fraction please. I ask because I am quite confused about this. Also, please tell me why a twin engined bird necessarily has to compromise on FF. Does the flanker have a poor FF? I mean there is reason to believe that at one point F-18s did have better FF than Solah. I was under the impression that a larger internal fuel load (in proportion to empty weight) would contribute to greater FF. And in this regard, I see no such rule that two engines have to compromise on FF, MiG-31 is supposed to have excellent FF.
maitya wrote:There-in lies the issue - two engines will have to compromise on fuel-fraction (irrespective of whatever level of engine-technology involved e.g. F18).
<snip>


First thing first - the defn etc.
As you know, the fuel fraction is defined as teh ratio of the weight of the fuel to the gross take-off weight of the craft (including propellant) excluding external stores and it's a key factor in determining aircraft range. A good write-up is there in Wiki itself : Fuel fraction and Aircraft Range
It determines the effective range of an aircraft and is dependent on various factors like LD ratio, SFC, amount of fuel available to propel (as opposed to lift the weight itself) i.e. cruise fuel fraction.


Ok, let's try and deconstruct this, one at time and to the best of my ability (which can be wrong, so pls correct me) - let's first look at the comparable stats between a double-engined aircraft (MiG-29A) and a single-engined F-16A (the one with PW engines, F100-PW-200, and not the later GE ones) - apples vs apples as much as we can, pls.

---------------------------MiG-29A---F16A
Dry-Thrust-(each)----------50kN------66KN
SFC-(each)-----------------75Kg/KNh--73Kg/KNh

Engine-Weight-------------1055Kg----1420Kg
Total-Weight-------------11000Kg----7390Kg
Fuel-Weight---------------3440Kg----3250Kg

Fuel-Weight:clean-weight-----23%-------31%
Engine-weight:Clean-weight---15%-------13%

TcWR (Thurst-to-Clean Weight-Ratio) both approx 0.7

So the key indicator/poser is why is that even after having almost comparable Dry SFC figures and a TcWR figures (of around 0.7) why does a twin-engined 29 has lower range than a single-engined F-16.

1) Weight Considerations:
Looking at the weight comparisons, one thing is pretty obvious, both F-16 and the 29s have very comparable weight structure except for the ratio of Internal fuel is to Clean weight (so only with max Internal Fuel) ~ 7-8%.

Ditto with F-18 vs F-16 comparison (haven't got the exact figures, but as Vina-ji says above).

There can be many reasons as to why this gap is there (including other factors like type of material used, weight of subsystems etc- though with around 3% composite usage in F-16 not sure if that's any deciding factor) but a large chunk of this % is also attributable to additional dead weight of plumbing, fuel mgmt and distn across two engines, so on and so forth.

Another important point to consider is the % of engine weight compared to Clean weight (MiG-29 15% compared to 13% of F-16), which means 2% of the 9% is contributed by the addn engine itself.
So, on the ground (i.e. excluding flight characteristics), the proportion of fuel available for propulsion is less in a MiG-29A compared to that of a F-16A - and quite a bit of it is due to the complexities of having to cater for an additional engine etc.

2) Aerodynamic Consideration:
This is where it gets tricky - as Range (and thus Fuel Fraction) is directly proportional to the ratio of Lift Coeff to Drag Coeff (and inversely to wing surface area as well).
Plus SFC as well, but while comparing MiG-29 and F-16 with comparable SFCs, this can be ignored.

IMO (and speculating), any double engined aircraft (with two engines closely fitted) there's an additional penalty to be paid in the lifting-body lift (and drag) compared to a classical single-engined design like a F-16. Having said that, normally lifting-body lift is more dependent on the top surface of the body - which is not effected, except for a proportionate increase in area (than a single-engined plane) due to the constraints of trying to fit an additional engine? But increase in body-area normally increases the body-drag (skin-friction drag) impacting the body lift-to-drag ratio (thus impacting the range and thus the fuel fraction as well).
Experts need to provide some gyan on this.

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Re: LCA News and Discussions

Postby SaiK » 10 May 2012 17:04

chacko, sounds valid interesting point. for the parameters is the chase plane that is measuring or the telemetry devices? again if it is all visual aspects, then the chase plane can provide all those.. if the parameters are specific to non visual aspects, then what you are saying is we have telemetry devices installed for both the chase plane and the test plane, and then we diff it!. sounds good. it would be also more precise way to measure.

but, in this case rather than LCA IAF took off first, is more valid in the sense both being off the same platform..

however, we have design changes, and we have control laws changes for nLCA.. so, we have that factor into measurements.

I am not sure, we would have invested in that approach is my feeling.

Now, if we know what parameters are being measured could reveal actual functions of the chase plane.

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Re: LCA News and Discussions

Postby Austin » 10 May 2012 17:12

There was this famous statement by a F-16 pilot who held many BFR/DACT with older Mig-29 from Germany and others ...he said the best way to defeat the Mig-29 in air is to make to run out of fuel and that does not take much long ....if you engage it soon then you are dead.

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Re: LCA News and Discussions

Postby Yogi_G » 10 May 2012 17:51

Austin wrote:There was this famous statement by a F-16 pilot who held many BFR/DACT with older Mig-29 from Germany and others ...he said the best way to defeat the Mig-29 in air is to make to run out of fuel and that does not take much long ....if you engage it soon then you are dead.


But the f-16 pilot will have to survive that time period what with the fulcrum's cue on sight lock on :D. The new plumbing on the mig-35 should go a long way in addressing the fuel efficiency and utilization.

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Re: LCA News and Discussions

Postby SaiK » 10 May 2012 19:09

The reason, that I am an ardent fan of Kaveri next generation. Efficiency and control laws can be perfected.. thrusts maximized, vanes invented, flows maintained to any mach., and turns where the engines can choke handled for efficency and performance.

There is a lot to gain FADEC, and if done right, can better P&W or GE performances. We can do it, and must be done all by ourselves.. Think about Mig29k/ovt/35s with our own Kaveri.

OLS is a top feature that can scare any stealth power.

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Re: LCA News and Discussions

Postby PratikDas » 10 May 2012 20:08

I don't know why, but the close-up image of the LCA NP-1 in its first flight followed by the LCA chase aircraft has been taken off the Facebook album. It is a great image and loaded with symbolism . I'm posting the image here again, linked to imageshack this time, just in case the link in the older thread stops working.

Image

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Re: LCA News and Discussions

Postby Eric Leiderman » 10 May 2012 20:42

Wow that is one good looking aircraft, the difference in length of the landing gear is there for all to see also the robustness of same.
the angle of the photograph might be a contributing factor in the perception of length too. So the ground clearance of the NLCA is like an SUV compared to a coupe. Go NLCA.

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Re: LCA News and Discussions

Postby SaiK » 10 May 2012 21:12

lobes and legs, is all that takes to attract men. NLCA has done it [chappal-less kat].

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Re: LCA News and Discussions

Postby NRao » 10 May 2012 21:42

Eric Leiderman wrote: So the ground clearance of the NLCA is like an SUV compared to a coupe. Go NLCA.


Need that clearance for both take-off and landing. Specially for a ramped take-off (have you had a vehicle's tail hit the curb when trying to suddenly turn into a rather steep driveway?).

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Re: LCA News and Discussions

Postby negi » 10 May 2012 21:47

Ah so Maitya sir finally chooses to come out of lurk mode only to give a nice wrap on my knuckles . :oops:

Boss I am still not convinced about the relationship between FBW and wing area , will post something in newbie dhaga in a day or two.

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Re: LCA News and Discussions

Postby SaiK » 10 May 2012 21:48

more importantly the spring action, that causes the airframe to impact on landing.

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Re: LCA News and Discussions

Postby suryag » 10 May 2012 22:10

Flight test update

LCA-Tejas has completed 1848 Test Flights successfully. (09-May-2012).
(TD1-233,TD2-305,PV1-242,PV2-222,PV3-342,LSP1-74,LSP2-207,PV5-36,LSP3-50,LSP4-52,LSP5-82,LSP7-2,NP1-1)

from

LCA-Tejas has completed 1846 Test Flights successfully. (08-May-2012).
(TD1-233,TD2-305,PV1-242,PV2-222,PV3-341,LSP1-74,LSP2-207,PV5-36,LSP3-50,LSP4-52,LSP5-81,LSP7-2,NP1-1)

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Re: LCA News and Discussions

Postby Kartik » 11 May 2012 01:31

Jaeger wrote:Is it just me or is the Navy's blue-grey paint job MUCH better-looking overall than the IAF Tejas' 2-colour scheme? In fact I prefer it to the std IAF Tipnis grey as well as the Navy's 'ghost' grey on the Harriers as well as the lighter Grey on the 29Ks... the blue-grey mix seems to be a lot 'richer' (TFTA?) than the Tippy and other greys...


Its not just you- I agree as well. the Navy's dark gray scheme looks better and the lighter gray radome looks good as opposed to the IAF's two tone gray scheme.

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Re: LCA News and Discussions

Postby SaiK » 11 May 2012 07:30

http://3.bp.blogspot.com/-1iSrdYMEwmg/T ... 0/NP11.jpg
Is there a difference in the rear undercarriages viewed against the flying one above?
between tarmak one taken photo, and the final flying, looks like they changed it.

The tarmak one almost resembles LCA rather (check the chase).

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Re: LCA News and Discussions

Postby srai » 11 May 2012 07:51

suryag wrote:Flight test update

LCA-Tejas has completed 1848 Test Flights successfully. (09-May-2012).
(TD1-233,TD2-305,PV1-242,PV2-222,PV3-342,LSP1-74,LSP2-207,PV5-36,LSP3-50,LSP4-52,LSP5-82,LSP7-2,NP1-1)

from

LCA-Tejas has completed 1846 Test Flights successfully. (08-May-2012).
(TD1-233,TD2-305,PV1-242,PV2-222,PV3-341,LSP1-74,LSP2-207,PV5-36,LSP3-50,LSP4-52,LSP5-81,LSP7-2,NP1-1)


PratikDas wrote:Image


That's 2 LCAs flying ... one as a chase plane. So that would count as 2 test flights.

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Re: LCA News and Discussions

Postby Cain Marko » 11 May 2012 08:05

So the key indicator/poser is why is that even after having almost comparable Dry SFC figures and a TcWR figures (of around 0.7) why does a twin-engined 29 has lower range than a single-engined F-16.


Maitya garu, no ji please. My reasoning is a little straightforward - the 29 has lower range simply because it is heavier and carries proportionally less fuel. In your figures, it would be the fuel wt:clean wt ratio that makes all the difference. IOWs, if 29 carried as much fuel as 16 (in proportion to it's weight), it's range would be similar and vice versa (if a F-16 carried only a fuel amount that was 30% of it's empty weight). And this is borne out by the MiG-29M, which increases fuel weight (in terms of %age) to F-16 levels. Range is then identical on internal fuel.

The plumbing, hydraulics etc could of course be a factor, but it cannot explain such a discrepancy in range (can it?). As far as drag is concerned, again the 29 is supposedly draggier, esp. after it is loaded with externals (EFT, AAMs etc). But this could be attributed to numerous factors - pylon design, missile weight etc.

Now the question is - why did the 29 carry such a small amount of internal fuel volume in the first place? I feel this was by design - FSU fighter doctrine REQUIRED tremendous control via GCI. If the design was poor or the technology was really backward as has been suggested (no composites for e.g.), they couldn't have come up with the M design within literally 3-4 years of Mig-29A induction. As the man said, "The Russians don't take a dump without a plan" - the plan was this is a battlefield level fighter, and that is it. Nothing multirole reqd. The moment a multirole requirement came up, they could bring the 29 to F-16 levels in a very short span of time (at least in terms of range)!

Dragging the whole thing back to the LCA - if this kind of achievement was possible with the fulcrum, why not the LCA? Why not a stepwise approach?

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Re: LCA News and Discussions

Postby SidSom » 11 May 2012 08:43

srai wrote:
suryag wrote:Flight test update

LCA-Tejas has completed 1848 Test Flights successfully. (09-May-2012).
(TD1-233,TD2-305,PV1-242,PV2-222,PV3-342,LSP1-74,LSP2-207,PV5-36,LSP3-50,LSP4-52,LSP5-82,LSP7-2,NP1-1)

from

LCA-Tejas has completed 1846 Test Flights successfully. (08-May-2012).
(TD1-233,TD2-305,PV1-242,PV2-222,PV3-341,LSP1-74,LSP2-207,PV5-36,LSP3-50,LSP4-52,LSP5-81,LSP7-2,NP1-1)


PratikDas wrote:
That's 2 LCAs flying ... one as a chase plane. So that would count as 2 test flights.


I think you are referring to
http://forums.bharat-rakshak.com/viewtopic.php?f=3&t=5807&start=3800

where it is listed that LSP2 (KH2012) was the chase for NP1. And yes it is listed as 2 separate test flights.

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Re: LCA News and Discussions

Postby Singha » 11 May 2012 10:20

tejas being a small and fat belly a.c without a raised front end, if we add a dorsal fairing will end up looking like this
http://images.rcuniverse.com/forum/upfi ... 25038.jpeg

not a great picture to look at imo.

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Re: LCA News and Discussions

Postby Austin » 11 May 2012 10:41

Yogi_G wrote:But the f-16 pilot will have to survive that time period what with the fulcrum's cue on sight lock on :D. The new plumbing on the mig-35 should go a long way in addressing the fuel efficiency and utilization.


Thats why he said avoid engaging it and run it down , fulcrum also has IRST making silent tracking/engagement possible something F-16 never had , he had only BFM older Mig-29A with F-16C and A , no western pilot has had opportunity to BFM the later model Mig-29 ,fuel issue has been addressed M on wards Mig-29M/M2/K/35 have longer legs due to greater fuel.

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Re: LCA News and Discussions

Postby vina » 11 May 2012 10:58

Dragging the whole thing back to the LCA - if this kind of achievement was possible with the fulcrum, why not the LCA? Why not a stepwise approac


Oh boy. There we go again. Fulcrum has a 90KN class high thrust to weight ratio engines and uses TWO of them! We didn't /don't have that. That is why!

If you still wanted to go that route in the absence of such engines, like I said, all you can do is a smaller than Mig21 plane, with the Mig 21 planes, that can take off from Bangalore, do two loops and rolls over Hosur, put tail back between legs and head back and land at HAL!

As for Mig-29's fuel fraction, if it carried a similar fuel fraction of a F-16 earlier (before the upgraded engines currently), it would have had the performance of a barn door. That is probably why the fuel fraction was kept low. It is all a function of engine t:w ratio. If you are 6 or so, all you can have is Mig-21class. If around 8 or so, you can get F-16, 10 and above, you get F-22 class of performance. I mean performance like without serious compromises in other areas like being able to fly just to Hosur and back.

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Re: LCA News and Discussions

Postby Yogi_G » 11 May 2012 11:56

vina wrote:
If you still wanted to go that route in the absence of such engines, like I said, all you can do is a smaller than Mig21 plane, with the Mig 21 planes, that can take off from Bangalore, do two loops and rolls over Hosur, put tail back between legs and head back and land at HAL!


Wow, the mig-21 can take off in Karnataka, go into Tamil Nadu and come back, not bad at all. :P

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Re: LCA News and Discussions

Postby Austin » 11 May 2012 13:35

vina wrote:It is all a function of engine t:w ratio. If you are 6 or so, all you can have is Mig-21class. If around 8 or so, you can get F-16, 10 and above, you get F-22 class of performance.


Vina , The F-119 engine of F-22 has a T/W ratio of 9 , EJ200 of Eurofighter has T/W ratio of 10 and PAK-FA 117 engine has T/W ratio of 10.5

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Re: LCA News and Discussions

Postby Abhibhushan » 11 May 2012 21:08


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Re: LCA News and Discussions

Postby SaiK » 11 May 2012 22:21

Singha wrote:http://images.rcuniverse.com/forum/upfi ... 25038.jpeg

not a great picture to look at imo.

I was similarly thinking about placing a retractable fuel probe along the side lines of the top fuselage.

but the levcons could hinder.. we have to do a mig29 onlee
--

^^Abhibhushan :

If you are the author of the discussion, why not use this thread rather inviting others to a link. It is easier to discuss in BR, and more valuable. The fact that you are refering here is enough reason for you to discuss at BR.

Now, I assume you are the author who is responding to BR poster. Else, what is your opinion?

Story lines and tales, needs solid baseline.. and the premise of your tale is BR poster and his opinions. And, BR webmasters can view this as conflicting to BR posting/web discussion rules.

Create your own story, without coupling BR views, and then link it up here as your view point is however more valuable than responding to vina in a different website.

btw, did you check with Vina?

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Re: LCA News and Discussions

Postby Cain Marko » 11 May 2012 22:50

vina wrote:
Dragging the whole thing back to the LCA - if this kind of achievement was possible with the fulcrum, why not the LCA? Why not a stepwise approac


Oh boy. There we go again. Fulcrum has a 90KN class high thrust to weight ratio engines and uses TWO of them! We didn't /don't have that. That is why!

If you still wanted to go that route in the absence of such engines, like I said, all you can do is a smaller than Mig21 plane, with the Mig 21 planes, that can take off from Bangalore, do two loops and rolls over Hosur, put tail back between legs and head back and land at HAL!

As for Mig-29's fuel fraction, if it carried a similar fuel fraction of a F-16 earlier (before the upgraded engines currently), it would have had the performance of a barn door. That is probably why the fuel fraction was kept low. It is all a function of engine t:w ratio. If you are 6 or so, all you can have is Mig-21class. If around 8 or so, you can get F-16, 10 and above, you get F-22 class of performance. I mean performance like without serious compromises in other areas like being able to fly just to Hosur and back.


You say that the RD-33 was not available to us from Russia (which happened to have closer ties) but the US F-404 was? The RD-33 was lighter and smaller than the R25 on the 21, produced greater thrust, and had superb SFC. The performance, would be v.good in terms of range/thrust. What is the problem? The only issue I see (and that is in hindsight) would be spares after the breakup of FSU.

The MiG-29/F-16 issue:

The difference is hardly as pronounced as you suggest, might even favor the 29. If the MiG-29 carried about 4500kg of fuel with it's original empty weight (11tons) + 1000kg in weapons, TWR would be 16600/16500 > 1.0 (1.06).

In any case, the IAF is upgrading to the Mig-29SMT, which does carry more fuel, and probly even has a greater empty weight thanks to the fat back. Engine thrust remains the same. Don't see anyone complain about performance.

Otoh, the F-16 @ 7400kg + 3250 (internal fuel) + 1000 kg weapons (11650), TWR = 10800/11650 < 1.0 (~0.9)

Why should the 29's performance be that of a barn door and not the solahs? Esp, when the fulcrum would retain a better twr that was > 1.0?

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Re: LCA News and Discussions

Postby Kartik » 12 May 2012 01:37

Cain Marko wrote:
You say that the RD-33 was not available to us from Russia (which happened to have closer ties) but the US F-404 was? The RD-33 was lighter and smaller than the R25 on the 21, produced greater thrust, and had superb SFC. The performance, would be v.good in terms of range/thrust. What is the problem? The only issue I see (and that is in hindsight) would be spares after the breakup of FSU.


I don’t want to get into the argument because I’ve not followed it fully, but the likely reason as to why RD-33 was not chosen to power the prototype LCA fighters was because it was unreliable, and had serious issues with low MTBF, which had at times grounded most of the IAF’s MiG-29 fleet. It had low MTBO figures as well and the issue of its smoking engines wasn’t even partially resolved till the RD-33 MK came about. If anything, it was a wise decision not to do so since the F-404 has a good safety record worldwide and is considered reliable as well. The only pro for it was its cost, and its good T/W ratio. But that is not something that the F-414 cannot beat, so why raise this issue at all?

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Re: LCA News and Discussions

Postby negi » 12 May 2012 01:48

Tejas when conceptualised was supposed to be powered by Kaveri , Rd-33 dimension and size wise is a much bigger engine while F404 was closest to Kaveri's dimensions .

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Re: LCA News and Discussions

Postby Philip » 12 May 2012 01:57

CM,some valid points indeed.Had the IAF/DRDO resolved that the LCA MK-1 would primarily be a lightweight fighter to replace the MIG-21s ,it might've arrived much earlier.Through an incremental process,future variants could've enhanced the strike capability .I am posting an excerpt from an above post which highlighted the absurd and misleading statements about progress on aspects of the LCA.I mentioned some time ago (from an AM's first person account) how a DRDO boffin b-s'd APJ AK at a review meeting that Kaveri's arrival was just a few months away.

As a matter of fact, the Air Force must be concerned about the LCA project on a number of counts. Firstly, the Air Force must be concerned about the proclivity of the DRDO on the under-assessment of tasks to be done. Let me pull out two instances from Air Marshal Rajkumar’s book. First; on assuming office in 1995, the Air Marshal’s professional assessment was that the TD1 was about five years away from its first flight. At the same time, the DRDO was confident that the first flight will take place ‘next year’. In actual fact, the first flight took place six years later. This sort of erroneous forecast makes forward planning difficult for the Air Force. Second; the TD1 airframe was rolled out prematurely for a function by the Prime Minister. There was really no technical reason for going through this drill at that particular time. Later, the airframe had to be pulled back, stripped and reassembled. It took about eighteen months and added substantially to the timeline for the first flight. Thus the Air Force gets concerned when not technical influences are permitted to intrude into a highly technical plan of action.


The horrified AM ,who had always held that the success of the project would primarily depend upon the engine chosen/developed,told AK that a fraud was being perpetrated upon the nation and whether the GOI/MOD was truly serious about the project.These words still hold true a decade+ later ,showing that the DRDO/ADA have learnt nothing from the HF-24s experience.It has been this lack of confidence in designing and developing an indigenous fighter by the IAF given the tall talk it has heard for decades,that has made it reluctantly look outside for its aircraft.However,the manner in which the IN has pursued the development of a naval variant needs to be sincerely applauded.It shows that when the DRDO/ADA/HAL/PSU whoever,work in tandem and close cooperation with the end-user ,it brings about results.

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Re: LCA News and Discussions

Postby SaiK » 12 May 2012 03:40

Wiki says 3000kg is from fuel weight, which is itself 40% weight considering empty weight of 6.5k kgs.
another 1ton odd is from GE 404/414 engines - 20%.
We have only 40% to play with, and we have achieved the lightest combat a/c.

It may be possible further depending on certain components and LRUs.

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Re: LCA News and Discussions

Postby Indranil » 12 May 2012 03:53

Abhibhushanji, I have said this time and again, I really respect your knowledge and in most ways I agree with your assessment. Whenever I have spoken on this topic, I have refuted this constant dishing of IAF as the negligent if not impairing step-mother of LCA.

However, DRDO has very limited resources too, financially, infrastructurally and manually. If DRDO keeps pandering to fulfill IAF's 'pragmatic' requests of fielding fighters within the upgradation cycle (once in 25-30 years), it would never be able to catch up. For example, if DRDO chose IAF's suggested path for LCA, LCA would have been flying in squadrons from 2005. But MMR/FBW would have never been developed and without them LCA would have looked very different, probably like the JF-17. MMR guys would have ben busy mating the weapons for the radar being strapped onto the LCA. May be from 2005, DRDO could start building the FBW and MMR. But then the next upgradation cycle of 2020-2025 would be impending. It would clearly not be possible to design and produce a new fighter with FBW and MMR from scratch within 15 years, just as it was for the previous cycle. Therefore, when and how would have DRDO with very limited resources broken this cycle and developed indigeneous capabities beyond being a systems integrator of foreign parts?

Clearly, whenever DRDO chose to field an indigenous world-class fighter with mostly Indian parts, it would take 30-35 years. IAF should have been prudent to elongate one of its cycles for this much-needed change or stretch it over 2 upgradation cycles by importing for the first cycle. If GOI did not understand this, shouldn't have IAF and DRDO collectively conveyed this to the decision makers instead of bickering about each other?

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Re: LCA News and Discussions

Postby Cain Marko » 12 May 2012 06:47

Kartik wrote:
Cain Marko wrote:
You say that the RD-33 was not available to us from Russia (which happened to have closer ties) but the US F-404 was? The RD-33 was lighter and smaller than the R25 on the 21, produced greater thrust, and had superb SFC. The performance, would be v.good in terms of range/thrust. What is the problem? The only issue I see (and that is in hindsight) would be spares after the breakup of FSU.


I don’t want to get into the argument because I’ve not followed it fully, but the likely reason as to why RD-33 was not chosen to power the prototype LCA fighters was because it was unreliable, and had serious issues with low MTBF, which had at times grounded most of the IAF’s MiG-29 fleet. It had low MTBO figures as well and the issue of its smoking engines wasn’t even partially resolved till the RD-33 MK came about. If anything, it was a wise decision not to do so since the F-404 has a good safety record worldwide and is considered reliable as well. The only pro for it was its cost, and its good T/W ratio. But that is not something that the F-414 cannot beat, so why raise this issue at all?


In hindsight Kartik, it was indeed a decent decision in terms of developing a new a/c. Whether the F414 decision is a good one, remains to be seen though considering US penchant to control it's arms' transfers.

My point though was simply to counter what Vinaji has been saying that such an engine was simply not available to India in the 80s.

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Re: LCA News and Discussions

Postby Cain Marko » 12 May 2012 06:59

indranilroy wrote:Abhibhushanji, I have said this time and again, I really respect your knowledge and in most ways I agree with your assessment. Whenever I have spoken on this topic, I have refuted this constant dishing of IAF as the negligent if not impairing step-mother of LCA.

However, DRDO has very limited resources too, financially, infrastructurally and manually. If DRDO keeps pandering to fulfill IAF's 'pragmatic' requests of fielding fighters within the upgradation cycle (once in 25-30 years), it would never be able to catch up. For example, if DRDO chose IAF's suggested path for LCA, LCA would have been flying in squadrons from 2005. But MMR/FBW would have never been developed and without them LCA would have looked very different, probably like the JF-17. MMR guys would have ben busy mating the weapons for the radar being strapped onto the LCA. May be from 2005, DRDO could start building the FBW and MMR. But then the next upgradation cycle of 2020-2025 would be impending. It would clearly not be possible to design and produce a new fighter with FBW and MMR from scratch within 15 years, just as it was for the previous cycle. Therefore, when and how would have DRDO with very limited resources broken this cycle and developed indigeneous capabities beyond being a systems integrator of foreign parts?

Clearly, whenever DRDO chose to field an indigenous world-class fighter with mostly Indian parts, it would take 30-35 years. IAF should have been prudent to elongate one of its cycles for this much-needed change or stretch it over 2 upgradation cycles by importing for the first cycle. If GOI did not understand this, shouldn't have IAF and DRDO collectively conveyed this to the decision makers instead of bickering about each other?



I agree with your assessment.

I also believe that a "less advanced LCA" could have been fielded a lot earlier than 2005. The BIG problem with defending INdia is that resources are always short (further exacerbated due to GOI's indecision). So operational needs have traditionally come first, and they should/could not be compromised for R&D needs. Can't blame IAF for having this attitude.

If God forbid, there is a catastrophic "aar paar ki ladhai" on two fronts starting 2013, of what use will the current LCA be ? I'd have taken a Bison with upgraded engines starting in the late 90s numbering around 150 today, over the current shortage. The Armed Forces have to think in these terms and maintain readiness - promises of delivering caviar in 6 months are of no use for a starved person, who needs daal-roti today.

Not that aiming for "caviar" is bad in itself - that is not the issue, such ambition is laudable as TKS points out but there is a point where it comes across more as grandiose dreams than anything else. And an AF that needs to defend the nation cannot count on dreams.

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Re: LCA News and Discussions

Postby Cain Marko » 12 May 2012 07:01

Philip wrote:CM,some valid points indeed.Had the IAF/DRDO resolved that the LCA MK-1 would primarily be a lightweight fighter to replace the MIG-21s ,it might've arrived much earlier.Through an incremental process,future variants could've enhanced the strike capability


You would think that this is simple enough but sometimes any critical analysis of DRDO/ADA is almost taboo here.

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Re: LCA News and Discussions

Postby shiv » 12 May 2012 07:12

Cain Marko wrote:
Philip wrote:CM,some valid points indeed.Had the IAF/DRDO resolved that the LCA MK-1 would primarily be a lightweight fighter to replace the MIG-21s ,it might've arrived much earlier.Through an incremental process,future variants could've enhanced the strike capability


You would think that this is simple enough but sometimes any critical analysis of DRDO/ADA is almost taboo here.


The problem is that so called critical analysis of aerodynamics is utter nonsense unless you actually have some engineering knowledge of how to make a heavier than air object fly and return safely. Every man and his uncle who bullshits confidently on here comes up with the sort of statement you have made.

Dazzle me with equations and I will shut up on this issue.


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