LCA News and Discussions, 22-Oct-2013

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_23360 » 30 Dec 2014 00:09

Vipul Dave wrote:
Krishnakg wrote:Delay in LCA FOC, is due to time taken for Cobham, in developing both IFR probe and the Quartz nose Radome, low rate of production & delivery and subsequent test flights to be done.
Interesting reads below.

http://www.cobham.com/media/917782/cob_m09_composite_technologies_fa.pdf

http://www.cobham.com/media/136971/SYSTEM%20GENERAL%20ME%20ADV10611.pdf

http://www.cobham.com/about-cobham/mission-systems/air-to-air-refuelling/products-and-services/hose-and-drogue-systems/refuelling-probes/air-to-air-refuelling-probes.aspx


Development of Tejas is an example of poor project management. All in charge need to ask whether they knew the Nose cone issue just before they ordered it or a long time ago? If they knew that a long time ago than why did they not ordered it in time. An ordering of Nose come and air furling probe just 6 months ago would have pushed FOC 6 months ahead since the both activity lies on critical path. (For those who have studied Project management). These all are simply eye wash. It is very much understandable that do develop some thing may take some time since it involves R & D challenges. However in-spite of knowing the problem, if you can not act in time and do a simple thing like identifying and ordering a party, yo are not a good project manager though you may be a very good technologist, engineer or designer. What we need is some good project managers to head the project.


They gave the FOC date(Dec. 2014) based on delivery date promised by the vendor, if vendor couldn't deliver on time, how can we blame project management?

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Re: LCA News and Discussions, 22-Oct-2013

Postby Cain Marko » 30 Dec 2014 00:21

Excellent discussion now...thanks to Rohit's facilitation and even Victor's persistence. We now have more clarity on the shortfalls of the LCA. Thanks also to forumers for providing information about areas where weight reduction might occur for the mk2. If the over engineering and weight can be managed, and the fineness increased, we may have the best single engined fighter seen so far as flight characteristics are concerned in the mk2....now the big question is when ?

Another question is...if all of the above are possible for the mk2, why not make this happen for the mk1 itself. A reduction in weight and drag should improve performance?

There is huge merit in the late.Commodore's recommendation that the mk1 be pursued with greater commitment, an additional order for mk1s should be forthcoming pretty soon hopefully.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Ramu » 30 Dec 2014 00:55

Cain Marko wrote:Another question is...if all of the above are possible for the mk2, why not make this happen for the mk1 itself. A reduction in weight and drag should improve performance?
.


If we try to achieve in Mk1, what else is left for Mk2? Engine and radar. It will delay mk1 further and mk2 bit more pointless.
Mk1 could achieve FOC earlier without a refuelling pod.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Cain Marko » 30 Dec 2014 01:02

Still another question reg. STR: although a marginal difference in str does not seem like such a big factor, esp. Considering hobs / hms combos, what happens when both opponents have such systems? Dowees str then gain more relevance?

I recall many on internet fora suggesting that slow speed maneuverability is inconsequential thanks to the emphasis on bvr, high speed and energy maneuvering, and hence the TVC on the MKI is of little use other than to facilitate fancy air show moves. However, the Russians, and more importantly the iaf, swear by it.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Cain Marko » 30 Dec 2014 01:06

Ramu wrote:
Cain Marko wrote:Another question is...if all of the above are possible for the mk2, why not make this happen for the mk1 itself. A reduction in weight and drag should improve performance?
.


If we try to achieve in Mk1, what else is left for Mk2? Engine and radar. It will delay mk1 further and mk2 bit more pointless.
Mk1 could achieve FOC earlier without a refuelling pod.


Fair enough.

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Re: LCA News and Discussions, 22-Oct-2013

Postby brar_w » 30 Dec 2014 02:18

Cain Marko wrote:Still another question reg. STR: although a marginal difference in str does not seem like such a big factor, esp. Considering hobs / hms combos, what happens when both opponents have such systems? Dowees str then gain more relevance?

I recall many on internet fora suggesting that slow speed maneuverability is inconsequential thanks to the emphasis on bvr, high speed and energy maneuvering, and hence the TVC on the MKI is of little use other than to facilitate fancy air show moves. However, the Russians, and more importantly the iaf, swear by it.


If both opponents have capable HOBS and HMS and largely comparable Instantaneous performance and nose-pointing, then you are going to have to seek advantages from elsewhere to maintain a healthy edge in combat capability over the enemy's kit. This could come from greater investments in BVR weapons, avionics, WVR weapons, training, tactics, stealth, Situational Awareness, data links etc. Ultimately things like ITR, TVC contribute to your overall offensive enterprise which itself is made of several different components. Having parity in pointing and HOBS/HMS does not necessarily equate to reverting back to the turning STR type of fighting, it means that you have to better other capabilities in order to get into an advantageous position without risking yourself to a shot from the opponent. Ultimately it boils down to who has the advantage in terms of technology gap, who holds the investment advantage (relative) and who has better training, tactics etc. Simply put if there is a segment in the a2a fight where two aircraft's approach parity in the sense that you are going to find it damn hard to secure anything other than a 50:50 success rate, or even say a 55:45 success rate (either way) then it is going to be advantageous for both parties concerned to avoid that area of combat and try to build an advantages in other areas so as to get a kill without as much risk. The cost of modern systems, pilot training means trading aircrafts is really not very attractive.

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Re: LCA News and Discussions, 22-Oct-2013

Postby SaiK » 30 Dec 2014 03:13

the reason the raptors went passive tracking and scanning (perhaps locking), with active burst mode active lpi radars. BVR game is interesting that LCA is not geared up to yet. LCA must think about raptors/jasoof in the future. probability - 100%. WVR, it is all about speed and turns, sustaining with longer range strikes.. kill before you see me or i will kill you before you kill me. for example OLS 50 will support to do a neater kill than 35. net centricity is another big booster, I can be stealthy all switch off, but jam resistant comms with an AWAC that feeds every thing to me. I am a proxy war machine in the sky!.. this will lead to UCAVs of the future.

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Re: LCA News and Discussions, 22-Oct-2013

Postby srai » 30 Dec 2014 03:52

Ramu wrote:
Cain Marko wrote:Another question is...if all of the above are possible for the mk2, why not make this happen for the mk1 itself. A reduction in weight and drag should improve performance?
.


If we try to achieve in Mk1, what else is left for Mk2? Engine and radar. It will delay mk1 further and mk2 bit more pointless.
Mk1 could achieve FOC earlier without a refuelling pod.


One can expect to see these incorporated at Mk1 MLU.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Sanjay » 30 Dec 2014 04:31

I think what is becoming clear to me is nobody is really sure how far off Mk1 is from ASR. Is STR/ITR really appalling or just not up to ASR (which seems to be set high) ?

Is the MK.1 a bad performing aircraft ? Not so sure now. Will it hold its own against a M2K ? Certainly against a -21 bison.

What is unfortunate is the war of words.

From what little hard info I have gathered, the Mk.1 will be a Mach 1.6 aircraft which has demonstrated not inconsiderable capability thus far - radar range of 50km (will increase), r-73, LGB and dumb bomb capability already demonstrated from airfields all over India - Leh to Sulur.

Given the radar type, Derby compatibility should be easy (ish).

As far as flight performance goes, we have Khokhar's comments which suggest a -21bis+ performance and better than M2K in some ways.

We do not seem to know much more other than the aircraft does not meet ASR for STR - and even then we don't know by what margin.

This may be stating the obvious but let us ask this - was it really realistic for ADA to build the best ever single-engined fighter in the world on their first shot ?

As an aside, I do have some concerns that comparisons with the Gripen are not necessarily being done like with like and that the Tejas may be closer in performance. But that is just a feeling.

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Re: LCA News and Discussions, 22-Oct-2013

Postby srai » 30 Dec 2014 04:50

Kartik wrote:Attended my first Aero India this Saturday. I won’t describe the difficulties in getting into the show, but once I did, it was quite alright. The highlight for me was the conversations I had with Cmde Jaydeep Maolankar, Test Pilot of the Tejas program and Cmdr Sukesh Nagaraj (Deputy Project Director, NLCA). I was lucky to spot Mao sir alone and walked up to him, introduced myself and spoke of my association with BRF and then we had a conversation on the Tejas program for half an hour..he was incredibly frank, friendly, didn’t hold back any facts and only left when he got a call from someone..here are the salient points of our conversation, some of which we already know but am listing it anyway.

...
- When asked about the STR and ITR rates of the Tejas, he simply smiled and said “it’s enough, let me put it that way”. When I queried him further, asking about the ASR that the IAF had set based on the Mirage-2000 and MiG-29’s STR and ITR, his smile vanished and he got serious. He said that when people look at 10 different brochures and come up with requirements, without looking at whether meeting all those requirements is even possible for ANY one fighter, they set themselves and the program up for failure. He was very frank about this, stating that even those brochure specs were just that- brochure specs that even those famed fighters sometimes don’t meet. But they were taken as benchmarks anyway and then, without even bothering to look at the technological base in India, the ASR was prepared.
- He was full of praise for the handling of the Tejas. It’s a true delight to fly and both he and Grp Cpt Suneet Krishna have tremendous confidence in the aircraft itself. He said that they both push the aircraft to its current limits without any worry since the FCS is very good. He did mention that they didn’t push the Tejas Mk1 to its limits at the airshow but just wanted to display that it is maneuverable enough.
...

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Re: LCA News and Discussions, 22-Oct-2013

Postby Surya » 30 Dec 2014 06:36

thanks Srai-

Kartik that was a great question - never would you have thought that the answer could be useful now

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Re: LCA News and Discussions, 22-Oct-2013

Postby member_26622 » 30 Dec 2014 07:07

^^ That is heartening news to hear from folks with first hand experience.

Now will IAF close the year with a big bang 200 MK1 jet order - to be delivered in 4 years flat? Things will move fast when the ball lands squarely in HAL's court - or they will risk dissolution.

Continuing on the 'lame' canard pitch for Rafale\Gripen, have thrust vectoring been considered for LCA. Here is why this is of interest http://en.wikipedia.org/wiki/General_Dy ... F-16_VISTA and http://theaviationist.com/2013/09/10/vista-f-16/ - last comment is key Thanks to its centre and the side stick installed in the front cockpit the F-16 VISTA can be re-configured after the take off to fly like a delta wings aircraft, like a canards one or like a large cargo airplane.

The weight penalty is an unknown factor though the paddle arrangement is better than Su-30 ball joint as quoted -This system is the cleanest mechanical design, aerodynamically speaking, and also reduces the nozzles’ radar signature (http://critical-me.blogspot.com/2007/12 ... a-was.html), maybe we can substitute it for the ballast - wishful thinking.


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Re: LCA News and Discussions, 22-Oct-2013

Postby brar_w » 30 Dec 2014 08:15

nik wrote:^^ That is heartening news to hear from folks with first hand experience.

Now will IAF close the year with a big bang 200 MK1 jet order - to be delivered in 4 years flat? Things will move fast when the ball lands squarely in HAL's court - or they will risk dissolution.

Continuing on the 'lame' canard pitch for Rafale\Gripen, have thrust vectoring been considered for LCA. Here is why this is of interest http://en.wikipedia.org/wiki/General_Dy ... F-16_VISTA and http://theaviationist.com/2013/09/10/vista-f-16/ - last comment is key Thanks to its centre and the side stick installed in the front cockpit the F-16 VISTA can be re-configured after the take off to fly like a delta wings aircraft, like a canards one or like a large cargo airplane.

The weight penalty is an unknown factor though the paddle arrangement is better than Su-30 ball joint as quoted -This system is the cleanest mechanical design, aerodynamically speaking, and also reduces the nozzles’ radar signature (http://critical-me.blogspot.com/2007/12 ... a-was.html), maybe we can substitute it for the ballast - wishful thinking.


viewtopic.php?f=3&t=5098&p=1772231#p1772231

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Re: LCA News and Discussions, 22-Oct-2013

Postby K Mehta » 30 Dec 2014 09:44

so basically based on kartik's q&a with mao it would be impossible for lca to meet the asr because it would be impossible for any aircraft to achieve or for the lca air frame especially without the levcons?

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Re: LCA News and Discussions, 22-Oct-2013

Postby Akshay Kapoor » 30 Dec 2014 15:54

indranilroy wrote:
Victor wrote:Indranil, stuff like turn rate, drag etc can't be pulled out of thin air by people who have no access to test records. I think the net warriors are basing their comments on what the IAF people are saying. If someone like Air Cmdr Khokhar says turn rate is not good, only two things are possible: turn rate is not good or Khokhar was a traitor. Take your pick. In my case, I choose Khokhar as the good guy.

Actually, I will be outright honest with this critique of the late commodore's article and I will not hold back anything because he is deceased. What I am hoping is that people call me out if my points are wrong, and the other moderators strictly scrutinize for any tresspassings.

1. Victorji, you and many others are guilty of putting words into the late Commodore's mouth. In that article, not once did he say the flying characteristics of Tejas is better than the Gripen, or the vice-versa. His critique is on ADA/HAL underscoring the development challenges for the Mk2 by piggybacking on SAAB's success with Gripen-NG. His critique is also on the IAF, who probably havn't finalized on what they want. He suggests that Tejas Mk1 should have been modified with all the upgrades in Mk2 barring the change of the engine. He suggests a much less riskier alternative wherein the air intakes of Mk1 are modified to fully exploit the INS6's thrust. He contends that IAF and ADA have not considered this alternative carefully which allows IAF to fill up the numbers much faster. In his own words:
The Tejas Mark I is far superior to the MiG-21 fleet that the IAF would have to operate to the end of this decade. In key respects, it is a better fighter than even the Mirage 2000. The Tejas Mark I should enter the IAF's combat fleet in larger numbers and the Tejas Mark II scaled down. This would allow the air force to retire the MiG-21 fleet sooner.


2. ADA probably feels that such a solution will not be enough (or will not be acceptable to IAF). In order to optimize the airframe, the wave drag needs to be decreased. This reduction in drag is done primarily with the addition of a body-plug. They feel that they should optimize this airframe, once and for all. Besides, an airframe with the 414 has be done for the Navy anyways.

3. Now I critique the Commodore's points with respect to the Mk2.
The new design features would include modification of the fuselage to accommodate the larger and heavier F414 engine. This would entail lengthening the fuselage, strengthening the fuselage and redesigning the contours. More thrust being produced by this engine (35 per cent more than the F404) means more fuel consumed and hence, the necessity for larger capacity fuel tanks. The obvious penalty would be in adding more weight, changing the area ruling (contours of the fuselage) which would increase the drag index, thereby negating some of the advantages of having a more powerful engine.

The addition of more weight would be counter-productive. However, some saving grace could be sought from redistribution of segments of the avionics components/LRUs and those of the new radar to get rid of the 200kg ballast that is carried in the nose bay to keep the centre of gravity within limits, an unheard of solution in good modern day fighters, only exception being Chinese fighters.

This is not totally true. The increase in thrust is from 90kN to 98KN (about 9%). Also the body plug is being added ahead of the CG and close to it. So if there is an increase in weight near the tail, it is not bad at all. In fact, probably the balast in the nose can be completely eradicated this way. The contouring to maintain smooth area ruling is a simple thing with modern computers, and is being overplayed by the Commodore. The adding of the extra weight does increase induced drag, but the body plug reduces wave-drag (the primary form of drag) at transonic speeds (the primary mode of operation for modern fighters). Also, a bigger engine does not mean more fuel consumption. The G414 has a better SFC than G404, which means for the same amount of thrust, it uses less fuel. Albeit at max thrust, it will consume more fuel, but those occassions don't last long in combat or general sorties.

The air intakes would have to be redesigned to ensure full benefit is derived from the new engine. This is one area that ADA has shied away from doing for decades. It is both understandable and acceptable that they lack expertise in this area, but it has to be addressed, so why not get specialist help for this.

I don't know enough about the second part. So, no comments.
Fool-proof cooling of the avionics bay is a safety requirement, since this area houses much sensitive equipment, including the four channel cards for the quadruple fly-by-wire system of the Digital Flight Control Computer, which, if affected by thermal transfer due to inadequate cooling, can have disastrous consequences. The quadruple control system will come to naught if all four systems fail in quick succession. Other sensitive equipment can also get degraded and thereby, jeopardise mission accomplishment.

A recent tender shows that they are actually recieving more air than required and would like to optimize the air intakes for Mk2. On this aspect, I have to place my trust in ADA. They can always lean on CABS as well for their experience with respect to cooling on the AEW&C project.

P.S. Notice that neither ADA, nor IAF, nor Commodore Khokhar ever spoke of canards or alternations in the wings. The wing will be reatined as is in Mk2. This is because the kink in the compound delta, the independently actuated slats, the suction effect created by the deposition of the boundary layer on the top and the turbulator strip together work like a close coupled canard (like on the Rafale/Gripen). This is not just a hypothesis. This was studied through wind-tunnel testing. For LCA Navy, they studied nose canards (like on the EF) as well. Again, they found the LEVCON was good enough. In fact, they seriously considered having LEVCONs on the AF version as these increased L/D at high AoA and would have aided in obtaining better STR. This plan has probably been dropped (in lieu of better visibility/RCS?).


Indranil,

I highly respect your domain knowledge and posting integrity like all other moderators. Wish I could say the same for some posters. However I think in this instance you may have inadvertently done an injustice to late Air Cmde Khokar and more importantly to facts. You have 'quoted' him from an article by Ajai Shukla. The first quote where he says Tejas is better than the Mig 21 and must be inducted asap is rightly attributed to him. Ajai Shukla quotes him as saying that. But all the others are Ajai Shukla's statements and even he has not attributed it to him. I did go back many pages in the discussion to see if you were referring another article written by Air Cmde Khokhar himself but could not find any. Perhaps you read the first part in quotes and then assumed the rest was from his as well. Or perhaps there is another article where he talks about weight, cooling etc which I have missed. In that case please be kind enough to link it again.

I have found this article by Air Cmde Khokhar. I am sure you have already seen it but in case others haven't it is very instructive. http://www.vayuaerospace.in/images1/Sel ... update.pdf

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Re: LCA News and Discussions, 22-Oct-2013

Postby Victor » 30 Dec 2014 20:13

Flying an LCA with FBW after flying a Mig21 would obviously be a better flying experience, like an automatic Volvo after stick shift Jonga. Point is, the IAF is still using the Jonga, not the Volvo because the Jonga is a better fighter. It's a pity it was not thought fiscally prudent to convert the Mig Bison to FBW. It is one of the most feared WVR fighters around even today. That would have taken the heat off the LCA while it matures.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Indranil » 30 Dec 2014 21:30

Akshay Kapoor wrote:Indranil,

I highly respect your domain knowledge and posting integrity like all other moderators. Wish I could say the same for some posters. However I think in this instance you may have inadvertently done an injustice to late Air Cmde Khokar and more importantly to facts. You have 'quoted' him from an article by Ajai Shukla. The first quote where he says Tejas is better than the Mig 21 and must be inducted asap is rightly attributed to him. Ajai Shukla quotes him as saying that. But all the others are Ajai Shukla's statements and even he has not attributed it to him. I did go back many pages in the discussion to see if you were referring another article written by Air Cmde Khokhar himself but could not find any. Perhaps you read the first part in quotes and then assumed the rest was from his as well. Or perhaps there is another article where he talks about weight, cooling etc which I have missed. In that case please be kind enough to link it again.

I have found this article by Air Cmde Khokhar. I am sure you have already seen it but in case others haven't it is very instructive. http://www.vayuaerospace.in/images1/Sel ... update.pdf

Thank you for the kind words. Only one of my quotes is from Ajai Shukla. All other quotes are from a guest article written by the Commodore for the Force magazine called the “The Better Alternative”.

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Re: LCA News and Discussions, 22-Oct-2013

Postby SanjayC » 30 Dec 2014 21:32

I read somewhere that when development of a new aircraft (LCA) was being discussed, one of the ideas was to base it on Mig 21 body, modernizing it and adding the latest bell and whistles. For some reason, the idea was rejected in favour of a brand new plane.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Victor » 30 Dec 2014 23:17

^ That's because the Mig21 production line had closed down and even the later Migs had not enough hours left in their airframes to justify the expense. Whatever could be done was done with Bison but not FBW.

BTW, the Mig21 is about the same size as the Gripen and bigger than the LCA. In a sense, the Gripen is a "reverse Mig21" with the stabilizer in front instead of behind the main wing. However the Mig is heavier (due to older tech) but has higher wing loading (ie. has a smaller wing), giving it better maneuverability including ITR.

Basically, even though the success of the LCA/LCA2 is a must, the very idea of a light fighter is out of date and not fully relevant to our needs now. What we need from both technical and economic reasons is as few aircraft types as possible that can do as many of the combat tasks as possible, IOW a multi-role aircraft which a short-range light fighter can't be. That's the rationale behind Rafale, Typhoon and especially F-35. It is something we can look at with minimal risk and expense in a 2-engined LCA which hopefully is what the AMCA turns out to be, instead of a completely new type with all the risks involved. What we have at present is a messy and expensive clutter of types thanks to the short-sightedness and greed of politicians and babus that treated HAL as a money machine.
Last edited by Victor on 30 Dec 2014 23:32, edited 1 time in total.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Shalav » 30 Dec 2014 23:22

Victor wrote:...However the Mig is heavier (due to older tech) but has higher wing loading (ie. has a smaller wing), giving it better maneuverability including ITR


That is incorrect saar. ITR is highest at corner velocity, corner velocity is more quickly attained with lower wing loading.

Corner velocity is the minimum speed at which the aircraft can pull the maximum G's.

If you have access to my worksheet, the formulas are all there.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Victor » 30 Dec 2014 23:35

^ OK. let's say it has better maneuverability and ITR than LCA.

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Re: LCA News and Discussions, 22-Oct-2013

Postby rohitvats » 30 Dec 2014 23:37

Victor wrote:^ OK. let's say it has better maneuverability and ITR than LCA.


Can you give a source/ data points to back this up? Or a scientific explanation?

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Re: LCA News and Discussions, 22-Oct-2013

Postby Victor » 30 Dec 2014 23:50

Rohit, higher wing loading is the biggest determinant of an "unstable" conventional aircraft which in turn is what defines maneuverability, including STR and ITR. Mig21 also excels in acceleration. Granted LCA has not touched its full envelope so far but expecting it to outdo the Mig with its huge wing is asking too much.

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Re: LCA News and Discussions, 22-Oct-2013

Postby PratikDas » 31 Dec 2014 00:00

Victor wrote:Rohit, higher wing loading is the biggest determinant of an "unstable" aircraft which in turn is what defines maneuverability, including acceleration, STR and ITR. Granted LCA has not touched its full envelope so far but expecting it to outdo the Mig with its huge wing is asking too much.


Hmm, ok.

Wing loading
In aerodynamics, wing loading is the loaded weight of the aircraft divided by the area of the wing.[1] The faster an aircraft flies, the more lift is produced by each unit area of wing, so a smaller wing can carry the same weight in level flight, operating at a higher wing loading. Correspondingly, the landing and take-off speeds will be higher. The high wing loading also decreases maneuverability. The same constraints apply to winged biological organisms.

<snip/>

Effect on performance
Wing loading is a useful measure of the general maneuvering performance of an aircraft. Wings generate lift owing to the motion of air over the wing surface. Larger wings move more air, so an aircraft with a large wing area relative to its mass (i.e., low wing loading) will have more lift available at any given speed. Therefore, an aircraft with lower wing loading will be able to take-off and land at a lower speed (or be able to take off with a greater load). It will also be able to turn faster.


Quoting ravi_g from the archives:
ravi_g wrote:From Opensource:
LCA Tejas Wing loading: 247 kg/m² (50.7 lb/ft²)
J-10 Wing loading: 381 kg/m² (78 lb/ft²)
F-18 Super Hornet - Wing loading: 94.0 lb/ft² (459 kg/m²)
F-16C Block 30 - Wing loading: 88.3 lb/ft² (431 kg/m²)

At Max. Combat Load (basically design limit)
LCA Tejas Wing loading: 13300/38.4 = 346 kg/m^2
J-10 Wing loading: 19277/33.1 = 582 kg/m^2
F-18 Super Hornet - Wing loading: 29937/46.5 = 643 kg/m^2
F-16C Block 30 - Wing loading: 19200/27.9 = 688 kg/m^2

Incremental Wing Load compared to competitor:
How loaded is J-10 compared to LCA Tejas : (582-346)/346*100 = 68%
How loaded is F-18 compared to J-10 : (643-582)/582*100 = 10%
How loaded is F-16 compared to J-10 : (688-582)/582*100 = 18%

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Re: LCA News and Discussions, 22-Oct-2013

Postby fanne » 31 Dec 2014 00:21

Victor Sahib,
Either you are a novice (nothing bad if you are trying to learn), or really taking us for fool (and for a ride). How can one even make a statement that a plane with higher wing loading is more maneuverable, its like saying the heavy person is faster!!
Jaguars have high wing loading (most among IAF fighters), they are not very maneuverable, but guess where it helps, low level flight, where wind gusts does not flip the plane (due to high wing loading). However all planes that want to maneuver in the horizontal plane will want to have low wing loading, whereas in vertical plane, the engine plays the most important role. So most great fighters have low wing loading and very high T/W ratio.
As for unstable aircrafts, delta wings are very efficient, the best among most wing types (low wing loading, large area to store fuel etc). Their biggest issue is while turning, if stable (Mirage 3, Viggen etc) the nose has to point upwards, killing lift (and thus energy and speed). After few turns its dead meat (however all deltas have excellent ITR, so good for slash and run attacks). When unstable, the tail goes up, nose down, thus conserving energy and speed.
LCA has both, unstable config and delta. It looks like all kinds of drags (from the pdf, the area ruling is bad between 5-6 m from the nose is bad, thus the plug) are hurting LCA. I suspect max AoA is not getting explored because of spin control is not finalized (PV-6). Once they figure that out, I believe they will push both ITR and STR by few angles.
rgds,
fanne
Last edited by fanne on 31 Dec 2014 02:58, edited 1 time in total.

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Re: LCA News and Discussions, 22-Oct-2013

Postby RKumar » 31 Dec 2014 00:31

Victor wrote:^ That's because the Mig21 production line had closed down and even the later Migs had not enough hours left in their airframes to justify the expense. Whatever could be done was done with Bison but not FBW.


Victor ji .... it is much cheaper to reactivate 2 gen production line as compared to setting up new 4+ gen production line. That too 2 decades back but someone was avoiding to take easy root as chances of early success was quite high.

Victor wrote:Basically, even though the success of the LCA/LCA2 is a must, the very idea of a light fighter is out of date and not fully relevant to our needs now.


I have heard similar logic from some other service, can someone reminds me please?? :roll:

Victor wrote: What we need from both technical and economic reasons is as few aircraft types as possible that can do as many of the combat tasks as possible, IOW a multi-role aircraft which a short-range light fighter can't be.


Economic reason, Kindly let us know how many Rafale can IAF buy and maintain while upgrading the infrastructure?

Technical, even without refuelling capability it has better capability and range then 60% of the IAF current asserts. And After refuelling, IAF can leave the whole west to LCA Mk1 and Mk2.

Even north-east defence can be left to LCA Mk1 and Mk2. While Su-30 can take the offensive and if required can support LCAs with buddy refuelling and AEW&C.

Victor wrote: That's the rationale behind Rafale, Typhoon and especially F-35. It is something we can look at with minimal risk and expense in a 2-engined LCA which hopefully is what the AMCA turns out to be, instead of a completely new type with all the risks involved. What we have at present is a messy and expensive clutter of types thanks to the short-sightedness and greed of politicians and babus that treated HAL as a money machine.


Lets move to FMBT but lets first junk MBT. Sounds similar. I am no technical expert but I can foresee that 2-engine LCA is completely new type. How you can't see even after being an expert???

Victor wrote:What we have at present is a messy and expensive clutter of types thanks to the short-sightedness and greed of politicians and babus that treated HAL as a money machine.


How Rafale is going to rescue IAF from the short-sightedness and greed of politicians and babus as it will be produced by HAL only??

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Re: LCA News and Discussions, 22-Oct-2013

Postby Victor » 31 Dec 2014 04:52

PratikDas wrote:an aircraft with lower wing loading...will also be able to turn faster.

True and I suppose I was imprecise with my wording, but this nominal rule of thumb has come down to us from WW1 which isn't relevant today--the definition of "maneuverable" has changed. You are not going into a turning spitfire-vs-Me109 dogfight dependent mainly on sustained turn rate with the F-16 and M2k. Now it's all a combination of fancy missiles, radar, ecm, TWR, acceleration, climb, quick turns (ITR), moments from all-moving control surfaces etc, even if we don't count networking. STR is only one variable in maneuverability and it was the variable in the days of the spitfire. ITR is by far the more important kind of turn in modern fighters. Case in point being the Mig21--can it turn inside the Zero which has very low wing loading? Of course not. But can it "outmaneuver" a Zero? Undoubtedly. Also, is it more "maneuverable" than the Phantom which has almost the same wing loading? Yes, it can run rings around the Phantom. There are also extremes that enter the picture--exactly how maneuverable do we want a fighter to be? Do we want a Starfighter with extremely high wing loading that cannot turn well but can fly fast at high altitude or do we want a Jaguar that can fly supersonic at treetop level? So the whole thing is relative and dependent on design goals. All these new multirole fighters are varying degrees of tradeoff between these extremes depending on what your need is.

fanne wrote:taking us for fool (and for a ride)

Arre bhai, what do I gain from taking you for a ride? And do I really have that much power? Just ignore me and move on. I'm trying to do my best (like we all are I'm sure) to make my voice heard about what worries me about India's air combat capability and what I see as the reasons and the fixes. I am at odds with a lot of people here and so be it, that's the nature of discourse. But let's not cause that to reveal our baser instincts and lack of class by resorting to personal abuse and accusations.

We all know that the PMO, MoD and Air HQ are paying close attention and take our views very seriously :D. We are all on the same side (I hope) so kindly take it easy.

Facts:
* old, falling-apart Mig21s are preferred by IAF over new build LCA.
* IAF is frustrated with HAL/ADA and has probably been officially told to shut up in public after AI 2011. But we have a long line of senior offices who open up loudly after retirement.
* HAL/ADA have an atrocious record of false advertising and outright lying.
* HAL/ADA have questionable motives in outright dismissing IAF concerns.
* IAF (and mois) are not berating the LCA, just ADA/HAL. In this I choose to take my ques from the IAF and nobody else.

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Re: LCA News and Discussions, 22-Oct-2013

Postby PratikDas » 31 Dec 2014 05:05

Victor wrote:
PratikDas wrote:an aircraft with lower wing loading...will also be able to turn faster.

True and I suppose I was imprecise with my wording, but this nominal rule of thumb has come down to us from WW1 which isn't relevant today--the definition of "maneuverable" has changed. You are not going into a turning spitfire-vs-Me109 dogfight dependent mainly on sustained turn rate with the F-16 and M2k. Now it's all a combination of fancy missiles, radar, ecm, TWR, acceleration, climb, quick turns (ITR), moments from all-moving control surfaces etc, even if we don't count networking. STR is only one variable in maneuverability and it was the variable in the days of the spitfire. ITR is by far the more important kind of turn in modern fighters. Case in point being the Mig21--can it turn inside the Zero which has very low wing loading? Of course not. But can it "outmaneuver" a Zero? Undoubtedly. Also, is it more "maneuverable" than the Phantom which has almost the same wing loading? Yes, it can run rings around the Phantom. There are also extremes that enter the picture--exactly how maneuverable do we want a fighter to be? Do we want a Starfighter with extremely high wing loading that cannot turn well but can fly fast at high altitude or do we want a Jaguar that can fly supersonic at treetop level? So the whole thing is relative and dependent on design goals. All these new multirole fighters are varying degrees of tradeoff between these extremes depending on what your need is.


You were not only imprecise, you were wrong and you were even trying to unload your bullcrap on other posters. Now you're using a whole lot of words to cover up the fact that you don't know jack.

You've bored this thread with a lot of derision regarding the LCA and you've portrayed yourself as someone who actually knows what he's talking about and should therefore be taken seriously. This is far from being the reality. I've been on BR for more than a decade. This is my second account. You're the first person I will be adding to my ignore list. Congratulations.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Karan M » 31 Dec 2014 05:13

PratikDas - congrats. Yet another realizes the reality. That aforesaid gent doesn't know jack but is busy gassing away (fudged up figures galore) complete bunk in order to run down an Indian program to further an obvious agenda.

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Re: LCA News and Discussions, 22-Oct-2013

Postby fanne » 31 Dec 2014 05:21

Victor sahib,
Humbly your statement regarding higher wing loading meaning more maneuverable is plain wrong. How wrong? It's like someone with a phd in math claims 2 is greater than 3. Either you do not know much about aeuronautics (while showing that you know a lot) or spreading Fud. I suspect the first, and unless you studied aeuronautics, it's hard to get that science. I don't hold you for not knowing, just on the pretending part.
The other conclusions that you draw are very dubious. Like Mig21 being more maneuverable than Lca. I can give you that mig 21 has better top speAd ( it was conceived as an interceptor), but I doubt str is better than tejas.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Karan M » 31 Dec 2014 05:25

Fanne ji, its but one of many such outlandish claims.

Fibs Galore wrote:...However the Mig is heavier (due to older tech) but has higher wing loading (ie. has a smaller wing), giving it better maneuverability including ITR
...
Mig21 also excels in acceleration. Granted LCA has not touched its full envelope so far but expecting it to outdo the Mig with its huge wing is asking too much.



Just to give folks an idea about the amount of fibs that are being peddled with junkyard science to back it up.

Air Commodore (Retd) Harish Nayani is a former LCA test pilot who has flown the MiG-21 Bison aircraft extensively and commanded a Bison squadron. This is what Nayani had to say.

"There is absolutely no doubt that the Mk 1, even if limited to 20 alpha would be many magnitudes better than the venerable Bison on all fronts. Notably, handling, safety, pilot comfort, and performance in the subsonic and trans-sonic regimes."


PS: Sjha writes: With reference to the 1995 ASR, the Mk-I has already exceeded the angle of attack (AoA) requirement of 24 degrees, by some two degrees (i.e it has achieved 26 degrees)
Last edited by Karan M on 31 Dec 2014 17:14, edited 1 time in total.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Shalav » 31 Dec 2014 05:55

--- removed ---
Last edited by Shalav on 31 Dec 2014 05:58, edited 1 time in total.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Shalav » 31 Dec 2014 05:57

Victor wrote:Rohit, higher wing loading is the biggest determinant of an "unstable" conventional aircraft which in turn is what defines maneuverability, including STR and ITR. Mig21 also excels in acceleration. Granted LCA has not touched its full envelope so far but expecting it to outdo the Mig with its huge wing is asking too much.


What is meant by highlighted statement?

They can't be both conventional and unstable! Conventional aircraft (ie non-fbw) by definition are stable.

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Re: LCA News and Discussions, 22-Oct-2013

Postby SaiK » 31 Dec 2014 16:45

perhaps victor meant 'gust response' on higher wing load. flying low with high wing load should have been done. from web, the f15-e strike eagle has around 650 kg/m2

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Re: LCA News and Discussions, 22-Oct-2013

Postby Karan M » 31 Dec 2014 17:13

Thakur_B wrote:Thakur_B
http://pib.nic.in/newsite/erelease.aspx?relid=65739

Quote:
Ministry of Defence
14-September, 2010 16:35 IST
Antony Dedicates AFNET to the Nation

Defence Minister Shri AK Antony today inaugurated the IAF’s gigabyte digital information grid – the AFNET (Air Force Network), dedicating it to the people of the nation, for their direct or indirect participation in the communication revolution.

The launch, a significant milestone in the IAF’s quest towards achieving a capability for Network Centric (NCW) operations was held in the presence of Union Minister of Communication & IT, Shri A Raja, Raksha Rajya Mantri, Shri MM Pallam Raju, Minister of State for Communication, Shri Sachin Pilot, Marshal of the Air Force Arjan Singh, Chief of the Air Staff, Chief of the Army Staff and other officials from the three services and members of the Industry.

Outlining the two-fold aim of ‘Network for Spectrum’ approach of the government – to facilitate the growth of national tele-density on the one hand, and ensuring modernization of defence communications with the state-of-the-art communication infrastructure, the network will have the potential to support net-centric operations, Shri Antony said.

A practice interception of simulated enemy targets by a pair of Mig-29 fighter aircraft airborne from an advanced airbase in the Punjab sector neutralizing intruding targets in the western sector was played out live on the giant screens at the Air Force auditorium offering a glimpse of the harnessed AFNET potential.

Further, various other functionalities contributing towards NCW were also showcased. These comprised of facilitating video from Unmanned Aerial Vehicle (UAV), pictures from an AWACS aircraft to the decision-makers on ground sitting hundreds of kilometers away, providing intelligence inputs from far-flung areas at central locations seamlessly. This was possible mainly with the robust networking platform provided by AFNET.


Thanks. this just shows an AFNET demo wherein it transfers data & the IACCS detects an intrusion and schedules an intercept.
What the Navy stuff was talking of (which should translate to other AF ac as well) is cooperative targeting. One detects/guides, other fires.

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Re: LCA News and Discussions, 22-Oct-2013

Postby Thakur_B » 31 Dec 2014 17:39

Karan M wrote:
Thakur_B wrote:Thakur_B
http://pib.nic.in/newsite/erelease.aspx?relid=65739

Quote:
Ministry of Defence
14-September, 2010 16:35 IST
Antony Dedicates AFNET to the Nation

Defence Minister Shri AK Antony today inaugurated the IAF’s gigabyte digital information grid – the AFNET (Air Force Network), dedicating it to the people of the nation, for their direct or indirect participation in the communication revolution.

The launch, a significant milestone in the IAF’s quest towards achieving a capability for Network Centric (NCW) operations was held in the presence of Union Minister of Communication & IT, Shri A Raja, Raksha Rajya Mantri, Shri MM Pallam Raju, Minister of State for Communication, Shri Sachin Pilot, Marshal of the Air Force Arjan Singh, Chief of the Air Staff, Chief of the Army Staff and other officials from the three services and members of the Industry.

Outlining the two-fold aim of ‘Network for Spectrum’ approach of the government – to facilitate the growth of national tele-density on the one hand, and ensuring modernization of defence communications with the state-of-the-art communication infrastructure, the network will have the potential to support net-centric operations, Shri Antony said.

A practice interception of simulated enemy targets by a pair of Mig-29 fighter aircraft airborne from an advanced airbase in the Punjab sector neutralizing intruding targets in the western sector was played out live on the giant screens at the Air Force auditorium offering a glimpse of the harnessed AFNET potential.

Further, various other functionalities contributing towards NCW were also showcased. These comprised of facilitating video from Unmanned Aerial Vehicle (UAV), pictures from an AWACS aircraft to the decision-makers on ground sitting hundreds of kilometers away, providing intelligence inputs from far-flung areas at central locations seamlessly. This was possible mainly with the robust networking platform provided by AFNET.


Thanks. this just shows an AFNET demo wherein it transfers data & the IACCS detects an intrusion and schedules an intercept.
What the Navy stuff was talking of (which should translate to other AF ac as well) is cooperative targeting. One detects/guides, other fires.


Alright. IAF has been very very tightlipped about the ODL and it's status otherwise.

Question: Do navy harriers use Link-2 to communicate like other navy assets?
Also, how many fighters would be able to share data in a group using ODL ?

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Re: LCA News and Discussions, 22-Oct-2013

Postby SSridhar » 31 Dec 2014 19:49

On the question of OBOGS, was it not announced in 2010 itself?

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Re: LCA News and Discussions, 22-Oct-2013

Postby Victor » 31 Dec 2014 20:13

Shalav wrote:
They can't be both conventional and unstable! Conventional aircraft (ie non-fbw) by definition are stable.

They can. I meant an aircraft like F-117 which shouldn't be able to fly but does due to FBW.

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Re: LCA News and Discussions, 22-Oct-2013

Postby putnanja » 31 Dec 2014 20:33

Victor wrote:
Shalav wrote:
They can't be both conventional and unstable! Conventional aircraft (ie non-fbw) by definition are stable.

They can. I meant an aircraft like F-117 which shouldn't be able to fly but does due to FBW.


Isn't that what Shalav is saying? F-117 cannot be said to be conventional aircraft in any sense. It has a highly unstable design (conventional aircraft are stable) and need FBW for it to fly.

Stealth aircraft

... Highly-stealth aircraft like the F-117 Nighthawk are aerodynamically unstable in all three axes and require constant flight corrections from a fly-by-wire (FBW) flight system to maintain controlled flight.[15]
...


Conventional aircraft are stable and can be controlled using hydraulic controls instead of FBW.


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