ADA Tejas (LCA) News and Discussions

[pankaj nema]

@ersakthivel

The day DERBY missile is test fired success fully from LCA MK 1
ALL criticism will come to an end

It will create such a huge pschyological impact on BOTH
Indian as well foreign defence watchers ; critics and enthusiasts

It will signify that the entire Tejas mk 1 programme
has reached the " business end " of its journey

 

[power_monger]

@ersakthivel

The day DERBY missile is test fired success fully from LCA MK 1
ALL criticism will come to an end

Sorry i am not a expert,but does firing DERBY missile successfully gives any indications on the air superirity of the tejas in terms of manevourability and rigidity of the aircraft?

 

[ersakthivel]

Sorry i am not a expert,but does firing DERBY missile successfully gives any indications on the air superirity of the tejas in terms of manevourability and rigidity of the aircraft?

@ersakthivel

The day DERBY missile is test fired success fully from LCA MK 1
ALL criticism will come to an end

It will create such a huge pschyological impact on BOTH
Indian as well foreign defence watchers ; critics and enthusiasts

It will signify that the entire Tejas mk 1 programme
has reached the " business end " of its journey

When they entered MMRCA competition, TYPHOON, RAFALE, GRIPEN did not fire their primary long range BVR missile METEOR . Also nether one of them had a functioning ASEA radar.

Missile firing has nothing to do with basic air frame design, top speeds, G turns and turn rates. its just electronic mating of the sensors of the plane with missile's guidance.

For example Su-30 MKI did not validate astra and air launched brahmos before it was designed . But now it is doing this.

DID Sukhoi modify the air frame for astra and brahmos carriage? . NO.

If tejas mk1 can fire the much challenging R-73 close combat missile , there is no problem in firing long range BVRs.

Calculations should have been made before manufacture about what kind of load and impact stress these missiles will impose on tejas.

in fact the weight gain and time delay on tejas mk-1 was exactly due to those fact, In the begining IAF asked for 60 kg less launching stress older R-60 as close combat missiles for tejas .

http://www.hindu.com/2008/03/09/stories/2008030958701000.htm

There have been several articles in the press critical of projects of the Defence Research and Development Organisation (DRDO) in general, and specifically the programme relating to the Light Combat Aircraft (LCA), now named Tejas, and the Integrated Guided Missile Development Programme.

Indeed, whenever a significant event that involves indigenous R&D, particularly defence-related, occurs, or a crucial decision is set to be taken, articles originating from within the defence "system," or from vendors who see their business prospects threatened, appear. The real facts relating to the programme need to be put in context.


Performance shortfalls

The two issues on which the LCA project is criticised are cost and time overruns, and performance shortfalls. As regards the so-called time overruns, when the zero/go date for the project is taken as 1983, the critics fail to mention that what was sanctioned in 1983 was an ad hoc Rs.560 crore, pending full preparation of the Project Definition Document (PDD) — which is a fundamental step even to start the design and development process. The costs were to be finalised based on the PDD.

This required the setting up of infrastructure in a hundred academic institutions and R&D laboratories and building up expertise to undertake the fundamental and application-oriented R&D required, and harnessing the design and engineering effort available largely in the public sector units for such a complex, state-of-the-art aircraft.

The Aeronautical Development Agency (ADA) discussed with Air Headquarters the Air Staff Requirement (ASR). Air Headquarters had requirements added to what was originally to be a replacement for the MiG-21. As a result, the ASR that was finalised was practically that for a Mirage 2000. But in the public perception the LCA remained as a replacement for MiG 21.

It look seven years, till 1990, to formulate the PDD. Based on this the ADA, in a report to the Ministry of Defence in 1990, gave a time-frame of seven years to develop the LCA and projected a financial requirement of Rs.4,000 crore. This included the building of four prototypes also.

There had been a 25-year gap since the only fighter aircraft ever indigenously designed, developed and manufactured, namely the HF-24 Marut, had entered squadron service. So the period of seven years to set up a more advanced R&D infrastructure and build up even the core personnel needed to develop the technologies that the LCA's ASR and PDD called for, was modest.
"Go-ahead"

After consideration, including by special committees, the Indian Air Force and the government gave the real operational go-ahead only in late-1993. Even that "go-ahead" covered the development of only two Technology Demonstrator Aircraft (TDA) without weaponisation.

The funding approved was only of Rs.2,000 crore — half the amount requested for full-scale development. The first TDA flew in 2001, eight years from the real operational 'go' date, despite much additional R&D work that had to be undertaken due to the U.S. sanctions imposed in 1998.



Comments appeared in the media in 2001 quoting IAF sources to the effect that what the ADA had achieved was just a flying machine that was yet to be weaponised. Considering the nature and scope of the approval accorded in 1993, what else was to be expected? Using the money sanctioned for two TDAs, the ADA built four. Full-scale development, for which another Rs.2,000-plus crore was finally sanctioned, thus started only in late-2001. Some 1,200 hours of flight testing was to be undertaken to secure Initial Operational Clearance (IOC) from the IAF.

At that point, apart from the weaponisation requirements the project had to undergo extensive redesign to accommodate an air-to-air missile chosen by the IAF, which was considerably heavier and longer than what had been specified till 2000. The IAF had again changed its mind.

This necessitated the complete redesign of the wing structure, using only composite materials in order to keep the weight within limits. The period of this redesign was also utilised to upgrade the avionics, to a completely open architecture.

Consequently, in "generational terms" the LCA is a fourth generation-plus aircraft with full networking capabilities. This made it more than comparable to anything the IAF had, and possibly would have, even after it acquires the 126 Multi-Role Combat Aircraft (MRCA) now on tender, with first deliveries due eight years hence.
On the engine

It is true that the Kaveri engine for the LCA that the Gas Turbine Research Establishment (GTRE) of the DRDO has been developing for 12 years has not yet met its technical performance targets and requires redevelopment. So far the GE 404 engine from the U.S., which powers the F-16 fighter-bomber, has been used to power the LCA. The problems the GTRE has with the Kaveri are not unusual in a complex fighter aircraft engine project being undertaken for the first time.

Moreover, the financial sanction of about Rs.320 crore given for engine development was possibly only to cover the Project Definition Phase and some high-risk technology development effort. We do not know of a first-of-type high-technology fighter aircraft engine being developed anywhere in less than a multi-billion dollar programme and a 20-year-plus development cycle.

Even Snecma, the sole fighter aircraft engine manufacturer in France, despite decades of experience in developing and manufacturing engines for Mirage III, V and F-1, took about a decade and $2.2 billion to develop the M-88 engine for the Mirage 2000. The development of the Kaveri is unlikely to cross $1 billion.

The LCA with a GE 404 engine has done 800-plus hours of flight-testing. Even with that engine the performance has been not only vastly superior to that of even the recently upgraded MiG 21 BIS (the IAF is operating almost 400 of the series), but it has shown itself to be comparable in many critical parameters to the Mirage 2000. Modifications to the aircraft structure are under way to reduce weight and improve engine performance.

When the GTRE's joint venture with a leading foreign engine manufacturer for further development is completed in the next four years, the Kaveri will be brought up to a performance level, superior to the GE 404. Fitted with it, the LCA will be truly comparable to the Mirage 2000 and in many respects even superior. And all this in an aircraft much lighter than the Mirage 2000.
Superior

As for network-centric capability, which intrinsically needs indigenous systems for secrecy, security and inter-operability, it is superior in the LCA compared to any aircraft in the IAF's inventory.

So it is a fallacy to think that we can continue the importing spree and still have such network-centric capability.

As recently as in 2005, the IAF's requirement for 126 new aircraft was only for an upgraded Mirage 2000. At Rs.120 crore to Rs.140 crore a plane, compared to at least double that amount for any of the aircraft types now bidding for the 126 MRCA, is not the LCA a highly cost-effective fighter for volume induction into the IAF?

As for development costs, the LCA has remained well within the sanctioned $1.2 billion — which is about the lowest anywhere. Time overrun in the strict sense is only by a year or two, despite the sanctions. A first-of-type aircraft of this degree of complexity has not been developed anywhere in the West or in Russia in less than two to three decades.

The F16 series that was inducted into the U.S. Air Force in 1975 is today at Mark 60. That is how aircraft of this level of complexity are improved after induction. That this imperative applies even more to the LCA has to be recognised.

It is for the Prime Minister and the Defence Minister to ensure that this effort is not belittled or scuttled, and that the LCA programme is given all-out support — as successive Prime Ministers have ensured for our atomic energy and space programmes.

(Ashok Parthasarathi was Science Adviser to Prime Minister Indira Gandhi. Vice- Admiral (retired) Raman Puri was Chief of Integrated Defence Staff to the Chairman, Committee of Service Chiefs, remaining closely involved with the inter-service weapons acquisition process from October 2003 to February 2006).

it will be nice if mother in law analysis writers touch upon these basic facts before writing ghost stories on tejas mk1.

Midway they changed it to R-73 which weighs 15 kg extra and induces much more launch stress, but more lethal than R-60.Also in flight refueling probe and many other requirements were added by IAF.

That was the reason for FSED phase-2 which started in 2004 and delayed the IOC.

the fact that tejas mk-1 fired r-73 in various configuration and validated proves there wont be any issue with any kind of BVR missiles.

 

[ersakthivel]

http://forum.keypublishing.com/showthread.php?99494-Beauty-Contest-Tejas-vs-Gripen/page2&


Tejas length: Inluding pitot tube 13.2m.
Gripen length: excluding pitot tube 14.1m.

http://forum.keypublishing.com/showthread.php?99494-Beauty-Contest-Tejas-vs-Gripen/page3

A tejas Vs mig-21 comparison in the page above. looks like they have similar length. Then WHy the fuss over length?

According to Mr Das, this 90 cm difference is all that has gone wrong with tejas!!!!

And it is the sole reason for tejas mk-1 being a lemon!!!!

Any technical reason behind such a claim or , Is it also a mother in law scientific analysis as most of his article is?

 

[power_monger]

Beauty Contest: Tejas vs Gripen - Page 2


Tejas length: Inluding pitot tube 13.2m.
Gripen length: excluding pitot tube 14.1m.
/QUOTE]

Whats the actual difference if Pitot tube is included in both?

 

[abhi_the _gr8_maratha]

I am thinking blessed as I don't got admission in IIT. cause chaps like this are professor their.
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he says hf24 marut was a design failure. But as I have stated it wasn't. It was a result of internation ban
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now this guy says mig21 better than tejas cause of mig21 have more speed.
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then my point is how hf14 marut is design failure cause it beats mig21 in speed.
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Airliners-India :: View topic - Last action heroes remember a fighter
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this guy is full of contrast.
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so by his logic tejas<mig21<hf24 marut . Hell, IAF Should induct more marut

 

[brahmastra11]

Again today Tejas rorared 3 times so far ..

 

[ersakthivel]

Intake Problems

There have been persistent reports of "intake matching" problems. What happens is the take off requirements of the intake are in direct contradiction to those required in transonic flight. You either accept poor take off and climb or face high spillage drag and engine surge at transonic speed. The solution is conceptually and mechanically very simple. Aeromodellers flying ducted fan models (PE Norman's ducted fan MiG 15 of happy memory!) used them. We used to call them "cheat intakes") .Spring loaded "blow in" and "dump out" doors are generally used. Even the dear old Hunter of Good Queen Victoria's times (well, almost!) had them. You could see them on the wing intake lips. As I write about this I realize that I have not seen any photos of such doors yet on the LCA . Perhaps some reader can post?
Aerodynamics
I have elsewhere mentioned that the LCA is aerodynamically blunt, its comparable equivalents being almost a meter longer. Any Aerophile will remind you the Douglas A4M with the 10% more power was actually 0.1 Mach slower than the less well powered Hunter Mk6 which had a longer fuselage and better entry Supersonic wave drag depends on the maximum cross sectional area and its position along the longitudinal axis as well as the entry aerodynamics i.e. from the radome tip to somewhere behind the rear cockpit bulkhead.

ADA needs to go over the contour and the cross section centimeter by centimeter. I am not exaggerating because it is so easy to end up with excess weight and wetted area if one becomes too enthusiastic. It is not for me to dare suggest but for God's sake use some "feel" along with the Analysis.

My betters have said that the aircraft has reached Mach 1.4 -(or was it Mach 1.6?).). Sorry, Guv'nor but the facts don't tie up! We seem to have on our hands an overweight aeroplane that is significantly stubby and has inlet problems and yet it reaches its design speeds?

Cap in hand, with fingers touching my forelocks (Alas! Long gone to happy hunting grounds!), I would say no, Sors, this bain't true! What may have happened is that the claimed speed has been achieved in a dive of around 300.

he writes his own research piece stating reasons for the inferior design of tejas based on assumptions like,

1.tejas mk-1 being a meter shorter than gripen C/D,

2.tejas mk-1 is overweight , so it not agile.(but ignores the fact that its contemporary "gripen " weighs 300 Kg more than tejas mk-1!!!). So according to him all the problems of tejas will vanish if it measures the same length as gripen,

No problem if tejas weighs 300 Kg extra and , has a 4 Kn lesser powered engine like its contemporary gripen.All agile manouvers can be conducted in hot and humid indian skies if only it measures a meter length more like gripen!!!.

As if its extra 300 Kg weight penalty and 4 Kn lesser engine power does not matter(because he holds the gripen as standard for tejas in weight comparison.)

3.It's intake is flawed because it does not have "cheat intake"!!!. never mind the auxillary air intake fitted on LSp-7 and 8 which is the production standard. According to ADA and HAL the purpose of these spring loaded aux intake is to provide extra air flow when needed in critical manoeuvre.

only his cheat intakes of Hunter fame can provide optimal solutions , not the aux intake designed by ADA and HAL!!!

4. Since air frame is not weighing Das gold standard 2300 Kg and landing gear at so and Kgs. the design can not pull the agile turns and tough manoeuvre. But he passes no such harsh judgement on the contemporary of tejas ,"gripen", which weighs 300 kg more than tejas mk-1 and a 4 kn lesser engine power!!!!.

Ofcourse he is all praise for gripen!!!. When pilot says the words Gripen all the extra weight will vanish and the plane can pull all tough manoeuvres!!!

5. All the wind tunnel studies conducted and , software studies that were conducted in IIT delhi, could not pin point the supersonic drag problem that he has readily identified with no studies!!!!

First thing that mr. das does not say is IAf wanted tejas to fit in the foot print of Mig-21 with high ITR flight regime of mirage-2000 with a biggest radar for a small fighter even before ADA was formed!!!!

He implies that ADA had its own choice in designing tejas. A big No. IAf demand is the basis of tejas fuselage dia and a blunt nose. Since if you have to fit the big dia radar on a fighter which is supposed to fit in the foot prints of Mig-21 it has to have a blunt nose. because a sharper nose means lesser dia radar.

We can see how myopic his critique is , when we see he never ever mentions the big radar of tejas even once.As far as he is concerned it is just an accessory for the pilot to play video games in cockpit with many MFDs.Their bigger detection and tracking range on both naval and air target was never even mentioned in passing.

The importance of this big radar can not be lost sense of , in the sensor fusion ASEA world of today. Many open sources mention the big powerful ASEA radar can be used as a stand alone Ew weapon all by itself.

What we see instead is his mother in law analysis based on aeromodel building days.

So based on his own assumptions he has already decided that tejas mk-1's top speed listed as mach 1.6 is a lie by ADA. he is implying that ADA is misrepresenting the specs by falsely claiming mach 1.6 dive speed as top speed!!!!

ofcourse there is a ballast weight of 200 Kg in tejas mk1 fuselage front.And for extra fuel capacity tejas mk-2 is going to be extended by half a meter or so. And this ballast weight will be eliminated in mk-2 when design is finally freezed.
Providing ballast weight is not uncommon in fighter design, since any new requirement could crop up which may lead to weight increase.

ADA did not go for weight rationalization in mk-1 in gret detail because IAf ordered only 40. Since both navy and air force are ordering more mk-2s all of these will be done in tejas mk-2 design phase.

And ADA sees no reason to worry about the bluntness of tejas as DAS implies, because fir the Ge-414 they will have bit larger dia fuselage , and the wing area of tejas too will be proportionatley increased since they are going to retain the same wing loading for tejas mk-2 as well. So the super sonic wave drag that stops the tejas from doing all tight turns exist only in Das's mind and not in ADA analysis and 2500 flight tests so far.

 

[abhi_the _gr8_maratha]

Arms race price war: India aims to undercut China in exports | idrw.org
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here is words of mr. Chandar , @Pulkit,
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tejas is likely to be inducted into IAF by end of this year after attaining FOC.

 

[ersakthivel]

Prof. Prodyut Das

What is interesting id mr. Das writes about the delta design of Mig-21with straight wing design of F-104 , as follows,

In the F104 Starfighter was definitely the more sophisticated Aircraft. The brilliant Clarence Johnson, possibly spoilt by an abundance of technology and resources, used a combination of a 3.5% thick straight wing with a state of the art J 79c engine wit a 17 stage compressor giving a pressure ratio of 12. The 3.5 % thick wing required CNC milling which was cutting edge technology in 1950s.

The MiG 21 team chose the innovative tailed delta concept. Initially derided by the West it was proved to be the best solution for the supersonic combat role. It combined lowest wave drag and yet avoided the problem of high induced drag of the pure delta which had to use "up" elevon" resulting in loss of lift during take off or a turn.
Engineering wise the Delta plan form of the tailed delta meant a reasonably thick wing which could be manufactured by traditional sheet and rivet methods.

but when it comes to tejas , the same tail less delta becomes drag prone!!!!

This cannot happen safely because the "g"s to be applied requires acceleration and lift. Unfortunately lift means drag particularly in AR Deltas whose induced drag is almost double of comparable swept wings.

SO induced drag becomes high in delta design of tejas which is highlighted as a flaw, but when it comes to mig-21 the lowest wave drag is praised.

Mig-21 was not designed to carry the amount of fuel and weapon load carried by tejas to fly the distance flown by tejas with a radar dia as high as tejas.

All the above mentioned loads were high on tejas. Still tejas manages to do all the things while physically remaining within the foot print of Mig-21 is always ignored by critics. Its dimensions, aerodynamic ratios and thrust to weight ratio are all reflective of the IAF demands , and not born out of free will of ADA.

 

[Pulkit]

I wish what he said comes true....
If thats exactly wat he said then i am happy that he didnt use the "IF" condition....

Arms race price war: India aims to undercut China in exports | idrw.org
.
here is words of mr. Chandar , @Pulkit,
.
tejas is likely to be inducted into IAF by end of this year after attaining FOC.

 

[ersakthivel]

Prof Prodyut Das is one of my favouite "lateral thinkers"

Here is an article of his that has appeared in the latst isue of "Vayu Aerospace"

I have seen your comments on prodyut das's latest piece " Ails of tejas",

can you ask a few questions to him like,

1.What is the scientific basis for claiming tejas as aerodynamically blunt? Is it a rule that ever 6 plus ton empty weight , 80 plus Kn single engined fighter should exactly measure the gripen length of 14.2?

2.Gripen weighs 300 Kg more in empty weight for its 14.1 meter length. Doesn't this extra empty weight affect the fighter's performance in indian hot conditions where lift gets reduced 12 percent and engine thrust also gets reduced by 10 percent as per Mr. das's old article?

3. mr das's ideal empty weight for a 14 meter single engined fighter is 2300 kg for airframe and 300 (or 700 ) Kg for a landing gear. All in all he thinks that any weight abpve 5.1 ton for a 14 meter , 80 Kn, single engined fighter is sub optimal. And because tejas weighs 6.2 tons empty he, thinks that it can not make agile turns or meet STR and ITR conditions.

But gripen what about gripen C/D which weighs 300 Kg more than tejas and has an engine which is 4 Kn less powerful than tejas. is it also a dead dog? Or will its canards perform some sort of black magic to evade all the ills that curse tejas?

4.Spring loaded Aux air intake is already placed in LSP-8 for the express purpose of providing extra air flow to engine when it is to produce full thrust at high AOA manouvers. But Mr. das has said he has seen none in Tejas? What is the truth?

5. Is ADA lying when it says that tejas envelope has been expnded to mach 1.6 at service ceiling and mach 1.1 at sea level as per his article?

6. Is Angle of attack a useless parameter? With out a decent angle of attack how is a fighter expected to pull high Gs in a fast turn in a dog fight or to evade missiles? Will IAF accept any fighter with 16 deg AOA?

7. Is every thing said in the following article is a lie according to Mr. Das?
http://www.airforcemag.com/MagazineArchive/Pages/1983/November 1983/1183f16xl.aspx

That has been accomplished in the F-16XL. In a cooperative program, General Dynamics and the Air Force have demonstrated that, at rather modest cost, the F-16XL delivers double the range or payload of the current impressive F-16 performance.


Hillaker said that the objective of the F-16XL program was to achieve a logical evolution from the basic F-16 that would provide significant improvements in all mission performance elements. At the same time, it would retain the fundamental F-16 advantage of low procurement and operating costs. Although the principal improvements were to be in range and payload capabilities, simultaneous improvements in all other mission elements were to be given equal emphasis. For example, survivability was to be a prerequisite to longer range. Higher military power (non-afterburning) penetration speed, lower observables, increased maneuver agility, and reduced vulnerable area increased the survival rate so as to be consistent with a longer-range/deeper-penetration capability. Many of the improvements resulted from the design team's innovative approach to integrating the weapons and airframe rather than hanging weapons on in the conventional high-drag, destabilizing manner.


To say that Hillaker's design team achieved its objectives is an understatement. Example: For an air-to-surface mission, the F-16XL can carry twice the payload of the F-16A up to forty-four percent farther, and do it without external fuel tanks while carrying four AMRAAM (Advanced Medium-Range Air-to-Air Missiles) and two Sidewinder AIM-9 infrared missiles.

With equal payload/weapons and external fuel, the mission radius can be nearly doubled. When configured for a pure air-to-air mission, an F-6XL with four AMRAAMs and two AIM-9s can go forty-five percent farther than an F-16A and can do so while conducting a combat action that is equal to thirty percent of its internal fuel.


As for penetration and survivability, the F-16XL can dash supersonically with a load of bombs at either high or low altitude. It can climb at high rates with the bombs aboard. And it has a speed advantage of up to eighty-three knots over the F-16A at sea level at military power setting and 311 knots on afterburner at altitude while carrying a bomb load.


Two additional capabilities of the F-16XL contribute to survivability. First is improved instantaneous maneuver ability coupled with greatly expanded flight operating limits (with bombs), and second is reduced radar signature resulting from the configuration shaping.

Importance of High Turn Rate


For a decade and a half, many fighter tacticians have stressed the paramount importance of being able to sustain a high turn rate at high Gs. The rationale was that with such a capability, enemy aircraft that cannot equal or better the sustained turn rate at high Gs could not get off a killing shot with guns or missiles.


With developments in missiles that can engage at all aspects, and as a result of having evaluated Israeli successes in combat, the tacticians are now leaning toward the driving need for quick, high-G turns to get a "first-shot, quick-kill" capability before the adversary is able to launch his missiles. This the F-16XL can do. Harry Hillaker says it can attain five Gs in 0.8 seconds, on the way to nine Gs in just a bit more time. That's half the time required for the F-16A, which in turn is less than half the time required for the F-4. The speed loss to achieve five Gs is likewise half that of the F-16A.


All of these apparent miracles seem to violate the laws of aerodynamics by achieving greater range, payload, maneuverability, and survivability. Instead, they are achieved by inspired design, much wind-tunnel testing of shapes, exploitation of advanced technologies, and freedom from the normal contract constraints.


The inspired design mates a "cranked-arrow" wing to a fifty-six inch longer fuselage. The cranked-arrow design retains the advantages of delta wings for high-speed flight, but overcomes all of the disadvantages by having its aft portion less highly swept than the forward section. It thus retains excellent low-speed characteristics and minimizes the trim drag penalties of a tailless delta.


Although the wing area is more than double that of the standard F-16 (633square feet vs. 300 square feet), the drag is actually reduced.

The skin friction drag that is a function of the increased wetted (skin surface) area is increased, but the other components of drag (wave, interference, and trim) that are a function of the configuration shape and arrangement are lower so that the "clean airplane" drag is slightly lower during level flight, and forty percent lower when bombs and missiles are added.

And although the thrust-to-weight (T/W) ratio is lower due to the increased weight, the excess thrust is greater because the drag is lower – and excess thrust is what counts.

9.Mr Das seems to be of the view that the same low wing loading cranked delta wing employed on tejas produces only skin friction drag and nothin else!!!!!

Then all the claims of hary Hilaker the legendary designer of F-16 Xl are simple lie perhaps?

Through cooperation with NASA, more than 3,600 hours of wind-tunnel testing refined the shapes that Harry Hillaker and his designers conceived. More than 150 shapes were tried, with the optimum design now flying on the two aircraft at Edwards.




Attack maneuvers resulted in G forces ranging to +7.0. With the heavy bomb load aboard, the F-16XL is cleared for maneuvers up to +7.2 Gs, compared with 5.58 Gs in the F-16A. This demonstrates how the designers were able to increase the aircraft weight while maintaining structural integrity and mission performance.

10. Also what is the drag implications of gripen's air intakes that are mounted way forward in the fuselage with canards extending for quite a distance in the super sonic shock cone path?

Is this a good arrangement or bad arrangement. What are its implications for wave, interference and trim drag?Since tejas does not have this arrangement does it score above or below gripen in drag parameters?

Please post his as your comment and get a response. It will give us more interesting info on tejas.

 

[ersakthivel]

http://www.airforce-technology.com/projects/tejas/
some sources mention empty weight of tejas is mentioned as 5680 kg . Is it true?

Is this true?

 

[bennedose]

@ersakthivel - actually I am not interested in arguing with Prodyut Das. He makes comments that irritate a lot of people but he does not come across as either stupid or ignorant. He is himself blunt and critical, but he churns up criticisms against programs that we know are difficult tech challenges.

His analyses about some things are refreshing. Have you read his opinion about how the HPT 32 was probably dumped too early without considering or doing what could have been done to keep them flying? Look at the article on his blog.

 

[ersakthivel]

@ersakthivel - actually I am not interested in arguing with Prodyut Das. He makes comments that irritate a lot of people but he does not come across as either stupid or ignorant. He is himself blunt and critical, but he churns up criticisms against programs that we know are difficult tech challenges.

His analyses about some things are refreshing. Have you read his opinion about how the HPT 32 was probably dumped too early without considering or doing what could have been done to keep them flying? Look at the article on his blog.

http://tkstales.wordpress.com/2012/05/11/the-tejas-debate-continues/]The Tejas Debate Continues | TKS' Tales[/url]

10. Given the present sortie rate and the fact is ( i am not sure if the figure is any longer secret but why take chances) "¦kgs overweight and the time required to build the lightened prototype and considering a production rate of about four airframes a year in the beginning it will be six years i.e. 2017 for the Mk1 to IOC . Ofcourse if we have another PR exercise with the current overweight A/cs the matter is different.The Mk 2, a comprehensive aerodynamic redesign, will take at least another 4-5 years thereafter.

The above was his prediction of time line for Tejas mk-1 IOC in his comments on may 26 , 2012.

But IOC-2 was achieved four years before his predictions.

He continues to insist the tejas mk-1 is overweight. But ignores its contemporary gripen C which is 300 Kg more empty weight than tejas. But when it comes to comparing lengths he insits gripen length is correct. But silent on weight.

There is no single engined RSS delta fighter in the world with 5.5 ton empty weight that has an equivalent combat range, power to weight ratio and weapon load of tejas and gripen.. Is there any?

Still he is clinging to the old ASR of LCA with 5.5 ton empty weight, completley ignoring the FSED phase-2 which added more weight because of demands from IAF for heavier air to air missiles, Now with refuelling probes and plumbing for the probe . It is only natural that old 5.5 ton weight can not be achieved.

He saya there is no aux intake. But there is one.

he says there is no need for tejas to reach 24 deg AOA, which is preplexing to anyone who knows a little about a fighter.

He is saying tejas is yet to fire missiles, which you have refuted.

he does not seem to be out of the box thinker. More of a loser type sob story (or SAAB story) writer.

Note how close this article comes after many reports from many guys about giving the development of mk-2 to SAAB with 51 percent equity partnership to them.

Pleas compare mr. das's version to AM philip rajkumar version on the same page,

Philip Rajkumar on May 1, 2012 at 6:01 am said:

philip rajkumar

I worked in the LCA project for nine years from 17 Sep 1994 to 31 Aug 2003 (actually 17 days short of nine years!). I was deputed to ADA by the IAF to oversee the flight test programme of the Technology Demonstration phase of the project. Having been on both sides of the fence i have a few points to make.
1. Development of a capable aeronautical industry is a small step by small step evolutionary process.Infrastructure and skill sets of the work force have to be built up over decades with considerable effort. All this requires investment of money and managerial resources. Mainly due to financial constraints and lack of vision in the IAF, HAL and the GOI we allowed capabilities built up during the Marut and Kiran programmes to atrophy. While the world leapt ahead with several technological innovations like fly by wire,digital avionics and use of composites for structures HAL did not run a single research programme because it was not the practice to do research unless it was linked to a specicific project.
2.The LCA project is where it is today thanks to one man-Dr VS Arunachalam who as the SA to RM in 1985 had the gumption and clout to go to the GOI and convince them that India could build a fourth generation fighter. It was a leap of faith no doubt.
3. HAL feels wronged about being asked to play second fiddle to ADA. This pique continues to hurt the project even today.
4. Without help from Dassault of France,BAE Systems UK, Lockheed Martin of the USA and Alenia of Italy we would not have succeeded in developing the fly by wire flight control system,glass cockpit,and composite structures for the two TD aircraft.
5. So far the flight safety record of the programme has been good. I pray every day that it remains that way. The loss of an aircraft early in the programme would have surely lead to its closure.
6.All pilots who have flown the aircraft say its handling qualities are very good. It means it is easy to fly and perform the mission.
7.It needs to be put into IAF sevice as soon as possible to gain more experience to iron out bugs which are sure to show up during operational use.
8.Programme management could have been better. IAF is to blame for washing its hands off the project for 20 years from 1986-2006. A management team was put in place at ADA in 2007.
9.Dr Kota Harinarayana and all those who have worked and continue to work have done so with great sincerity and dedication.
10.Indian aeronautics has benefitted immensely from the programme. It is a topic for separate research.
11. It was a rare privilege for me to have been given an opportunity to contribute to the programme by setting up the National Flight Test Centre and putting place a methodology of work which has ensured safety so far.
12. According to me the project can be called a complete success only when the aircraft sees squadron service for a couple of decades. We will have to wait but it is progressing on the right lines and we as a nation have nothing to be ashamed of.

he clearly says had IAF not washed its hands of tejas from 1983 to 2006(as late as 2006!!!),

had HAL shown a bit more co operation to ADA tejas delays could have been avoided.

mr. Das's version completley differs from IAF guy rajkumar who was involved in the project.

 

[abhi_the _gr8_maratha]

Export Potential of Tejas: Analysis | idrw.org
.
I think radar is total indian with little collaboration of israel. Ejection seats have TOT hence can be manufactured indigenously after some time.
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many calls tejas 60% indigenous but they forget one thing, cost of engine is 5 million, that's 18-20% of cost of single tejas. Seat also costs 1%,
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and out of 35 major avionics, only 3 are imported.
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So there no need to say tejas as assembled in india with foreign components. Cause only 10-15 are imported. And if kaveri would have been ready, it would have been 80% indigenous right now.

 

[Pulkit]

In the case of TEJAS we will have alternative to everything apart from engine in the coming next few years .....
In the next few years if we are hoping for Tejas to be exported then we need to have our own engine ....
And to be quite honest I DONT See that happening in atleast next 5-10 years ... So what can be done..??

Instead of US can we shift to Russia ?
Atleast they wont put sanction on us....

 

[bennedose]

mr. Das's version completley differs from IAF guy rajkumar who was involved in the project.

ersakthivel - Philip Rajkumar is a personal friend of mine and I have known him since I was a boy and he had just joined IAF. I do believe him - but I am not trying to set up a comparison. Das is out of the loop and has strong opinions. He has an ability (like Philip Rajkumar) to bring up technical points that 99% of internet forum jingos are unaware of and that is where his utililty lies - as a person who expands the mindscape of the average educated aerospace illiterate fanboy. Some people such as yourself with deeper knowledge are bound to have differences. One need not believe him or vote for him - but one can understand the complexity of issues involved and how some decisions taken along the road cannot be reversed and how things might have been if other design choices had been made.

 

[abhi_the _gr8_maratha]

his points are already proved wrong. I think Mr. Das brings those points which doesn't exist

 

[abhi_the _gr8_maratha]

Defence News - Export potential for Tejas : DRDO
.
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again Mr das proved wrong, production of 10 completed.
.
W. Selvamurthy, Chief Controller, Life
Sciences, Defence Research and
Development Organisation (DRDO),
said there could be a good export
market for Tejas, the country's first
indigenously built supersonic fighter
aircraft, if the Centre okayed it.
Speaking to The Hindu recently, he
said the DRDO had already received
enquiries for Tejas from various
countries.
The plane was given Initial Operating
Clearance (IOC) only recently by
Defence Minister A. K. Antony. The
Light Combat Aircraft (LCA) was the
star attraction at the recently
conducted Aero India air show in
Bangalore, in which 45 countries took
part.
RARE CAPABILITY ::
Saying India was among very few
countries in the world capable of
producing fighter planes, Mr.
Selvamurthy said that third world
countries, developing countries and
even some of the developed countries
were markets for Tejas.
Since the production cost, research
and development cost of the Tejas was
relatively low compared to the other
fighter aircraft, India could sell the
Tejas at a lower price.
Since the production models were
doing extremely well, there wouldn't
be any problem in obtaining Final
Operating Clearance (FCA) for the
fighter aircraft, he said.
In line with the requirements of the
Indian Air Force, the process of fine
tuning Tejas, including flight
envelope, flight manoeuvrability,
payload integration and other issues
have been taken up.
The fighter plane got the Final
Operating Clearance in the first
quarter of 2013, the official said.
PRODUCTION COMPLETED ::
Mr. Selvamurthy said out of 40 Tejas
aircraft ordered by the Indian Air Force
(IAF), the Hindustan Aeronautical
Limited (HAL) had already completed
production of 10. It had already been
figured in the inventory of IAF.
Another 20 aircraft would be
completed after the Final Operating
Clearance is given.
It is expected that an order might be
received for a large number of aircraft
in 2015. HAL had also geared up its
capacity building facilities, including
assembly line and others.
It planned to increase the capacity to
increase the number of aircrafts built
in a year to meet the growing demand.
The distinguished scientist said the
cost of aircraft, which stood around
Rs.130 crore, was expected to come
down once the HAL started large-scale
production of Tejas.
The country had been placed in
comfortable position as far as Tejas
was concerned as it was not depended
upon anybody for lifecycle support,
maintenance cost and others because
of the indigenous technology.