Sunday, 22 December 2013

Visitors' expertise forum: Where does the Tejas stand?

I am planning a piece that evaluates the Tejas as a fighter and looks at what operational role it could play for the Indian Air Force.

Views are solicited from visitors with strong experience in design and operations.

As always, a gold star for the best response, and a silver star for the most inventive one.



Anonymous said...

I had always felt that Tejas is unbalanced in that it's weight is more in the back and less weight in front if this is true then the plane has tendency to tilt backwards and the fly by wire system has to correct the tilt and make it fly straight. Normally this is not a problem at low speeds as it reduces the efficiency but high speeds it produces a wobble and the plane cannot reach high speeds . I have no idea as to why Tejas could not reach high speeds as I am not involved in Tejas but if it is producing a wobble at high speeds then the front portion needs to be lengthened so that there is more weight is in the front and center of gravity shifts more to the front. They can add weight with concrete blocks in front and modify the flight control software and try it out with some flights with different weights.

The inlets have to be redesigned and have to be bigger by 12 percent than Grippen NG inlets to get optimum performance at high speeds and at high altitudes.

The radome has to be of quartz to reduce the losses and thus can have best performance.

The wheels have to be positioned in the wings like Grippen NG to have more space in fuselage so that the fuel capacity be increased as anything below 5 thousand liters is not good enough and preferably be six thousand liters.

The new engine on MK 2 is GE 414 IN5 S 6 which can easily produce 110 KN of thrust in short bursts without any loss of engine life and in war it can produce 128 KN which is truly exceptional , I would increase wing surface area and increase the external load to 5 ton. Now two more weapon points can be added to the wings and I would add two long range missiles to the wing tips like SU 30 thus having 11 weapons points and having accessory fuel tanks can still be an option but with 6K liters in the belly and inflight refueling probe with mama giving juice when required would Increase the lethality of the Tejas.

The shape of the front as well as back of the body around the wings be changed as per the wave-patterns .

The wing tips need to be sharper to have better aerodynamic performance.

I feel Tejas MK 2 should have front canards if not should have Levicon as standard feature as that would increase the AOA further and I feel 28 to 30 degree AOA is possible as per my designing experience.

The brake problem can be sorted by having carbon fibre lining used in race cars with gaps increased in between the discs with propeller fins around the brake discs to have fresh air fanned in to cool the discs.

In all great effort by a team which almost 50 years back designed a plane and that too under the great expert Prof. Tank. All other aeronautical houses had huge experience with Dassault , Saab , Macdonald Douglas , Boeing and UAC with. Each having designed and produced atleast 5 successful planes.

It is very important last lap that is most difficult and if they quickly succeed in producing a prototype and quickly test it which should be lot easier now with the team having more experience would yield a top class product and in the same money tone spent in MMRCA project the can have 400 plus planes with twin engined version Tejas MK 3 be ready to be produced.


Parthasarathi said...

These are my own opinion on Tejas,

1) Structure: Almost fully composites with low RCA. But very small air intake! So we can safely assign 6 out of 10. If they can redesign the air intake then 7 out of 10.
2) Aerodynamics: Compare to Gripen, Tejas is much less stable and consume more fuel and very less AOA. Less speed also. So only 3 out of 10.
3) Engine: GE. Made engine is probably best in the class. No accident so far. So 8 out of 10.
4) Radar: ELTA 2032 MMR. still holds good. If we can integrate Israeli BVR. missiles with this radar ( which may not be that difficult as both are Israeli origin) then 7 out of 10. When AESA. Will be fitted then 8 out of 10.
5) Electronics: Glass cockpit, fly by wire, HOTAS. But all are common in generation 4 fighters. So 6 out of 10.
6) Armament: Ground attack capability: 2 out of 5 and air to air capability 2 out of 5 . ( No BVR. capability so far) So in total 4 out of 10.
7) Performance: Radius of action is only 300 km, no internal jammer, very less armament. No BVR. .So only 04 out of 10.
8) Maintainability: Not known to us. But hopefully it will be placed between Russian and French fighters of IAF. So around 5 out of 10. (Mirage 2000: 08/10, Mig 21 : 02/10.
9) Pilot comfort: All test pilots are really happy with this baby. So safely assume 6 out of 10.
10) Price: At 28 million it is damn cheap. Remember we have spent much more money per aircraft just to refurbish Mirage 2000. So safely 8 out of 10.

Total score is 57 out of 100. Not very high but not bad either. We have to compare spade with a spade. So let’s compare Deltas. It may be placed between Israeli Kfir (modified, C 12 standard) and Mirage 2000.
At the end of the day it is an Indian fighter. We know there is no comparison between Tata bus and Volvo bus. But Tata bus is cheap and can carryout exactly almost same workload like Volvo bus but in much crude way. So whether Tejas will be able to perform or not that is separate question but we should be proud that we can produce world class fighter.

Anonymous said...

In 1941 when Japan used carriers to attack that was a novel concept that was never thought of before. For defense of Singapore the British used two new battleships and both were neutralized within few minutes by planes and changed the concept of naval warfare . The concept I want to press is think out of box and have 200 naval versions of Tejas in Ladakh and 200 in Arunachal Pradesh in carved hangers in Himalayas with an attached carrier sized naval air strip attached to these airports and have 15 to 20 small airports like that would be a game changer as China cannot succeed in any attacks with air force support so close to the border and it is extremely difficult for Chinese to hit such small runway with dense airdefense.if the Chinese attack with an armored division then it an be knocked out In minutes with Tejas spraying Helinas from 10 miles above and whole armored division can be knocked out and the bomb load can precisely take out artillery and missile posts and any attempt to confront Tejas be dealt by a high end fighter like F 35 painting the targets and Tejas hitting those aerial targets. It is thus very important that Tejas naval version must succeed.


Anonymous said...

It would be a hybrid of sorts. I'll put it close to MiG-29 and F-16

Anonymous said...

Is this the comedy thread?

What a bunch of morons posting on this thread.

1. "Unbalanced" aircraft, concrete blocks...hahaha.

2. F-35 painting targets, Tejas hitting. ROFLMAO

Anyways, the fact that DRDO/ADA has bastardized IOC - Initial Operational Capability to Initial Operational "Clearance" tells us a lot about the way this program was managed.

120 LCAs is very similar to 124

Anonymous said...

@ Anonymous 23 December 10 01:33

The LCA doesnt have to be superior against a potential adversary in every field, just those that matter. The example of the experience of Folland Gnat serves to illustrates this point. Here we had an underpowered, underarmed aircraft (the Gnat) against a fast, aerodynamically superior opponent (the Sabre). The Gnat however could maintain a high sortie rate and with right tactics was able to overcome these weaknesses. The LCA, in my opinion, is the philosopical successor to the Gnat upgraded for modern air warfare.

Anonymous said...

Tejas MK1 is the equivalent of a Gripen C/D. So, it does all the JAS part of the JAS 39 Gripen, ie (Interdiction, Attack and Strike). It will get anti ship weapons and A2G cruise missiles in due course. A potent multirole package in a small and efficient form factor.

I do think that there will be one more software upgrade a year or so into FOC to take angle of attack to around 26deg or so and give the full 9G limit that the airframe is capable of. It can replace all the old Mig21s and Mig 27s and a whole bunch of older Jaguar fleet currently in service. The Mirage 2000s and newly built Jaguars have have been upgraded and have significant life left in them, but can replace them as well if needed (but that I guess the IAF wants to be replaced by the Rafale and hence another story).

Anonymous said...

Tejas should fill exactly the role it was originally designed for - to be the warhorse of the IAF by replacing the bulk numbers that constitute the MiG 21s.

Even though the LCA is far more capable than the MiG-21, but that's not how we should look at it. Rather we need to see its relative place in the IAF dynamic force mix, as it changes over time. IAF experts are sure to be doing a more clinical study. Here is a rudimentary "dynamic force mix"-

As an example...take the Su-30MKIs-
Its numbers would initially increase with time, then probably be upgraded twice, then reduce in a phased manner:
1st upgrade being to Super 30 standards with AESA, Brahmos, and more potent weapons.
2nd not attempting to describe (at this point we have no idea how technologies and warfare techniques will develop). But all one can say is that the original fighter should last till 2030 - 35. Just like these days the old MiG-21 design is on it's last legs. So would the SU-30 be.... by around 2030 - 35.

One should write on similar lines for all other IAF fighters, viz, MiG-29, MiG-27, Mirage-2000, Jaguar, Rafale, LCA, and possibly even the AMCA. Then one will get a much more cohesive and overall picture of the LCA's place in the IAF force mix. Else, it will be just half baked knowledge. But thats a lot of effort! Who will do this?

Proud of India, LCA, all test pilots and designers at DRDO and ADA. The LCA, various missiles , mars mission, nuclear submarine, aircraft carriers.... are morale boosters. And somehow, for some strange reason, the LCA is by far the BIGGEST morale booster!!

Strategenius said...

I strongly feel that the Tejas can be used in remote-controlled, multilevel swarm fronts to overwhelm and conquer the US District Attorney's office in NY and retake Tibet for Akhand Bharat. Pakistan will of course surrender once we achieve these feats and we can sell them several squadrons of the Tejas Mk 1 as an apparent minority appeasement but cunningly to enslave them to HAL's spare parts tyranny. Go Modi.

hyro said...

All the hullabaloo aside the plane is late most of its technology on the verge of obsolescence. That is ok it is still not vaporware. I seriously hope the plane is a start to better private Indian companies taking the mantle to at least develop the LRU's that are currently being imported. Accelerate the AESA radar program and the future versions should incorporate levcons or lerx and dsi. Although HAl keeps putting up these presentation on stealth I still think the Mark-II will only be gen 4.5+ that said why do we need a stealth platform are we gonna invade some other country.
Finally china reportedly pumps in 9B$ into its gas turbine program how ever bad Kaveri is at least complete the damn project

Anonymous said...

To anonymous 9.12

It seems you have no idea of aeronautical designing and testing and let me tell you that you would get a shock of your life when you come to know who I am and what were my achievements in aeronautics.i am retired now and thus I thought I could help with very limited output that I can give for which you can call me moron and I am fine with that.i would not ever write any advice as you all super duper intelligent people don't need that.i have been involved in few projects and I understand the pain to bring Tejas to this stage and I understand how important this achievement is to the ADA as well as to domestic defense industry and if they would have failed then keep paying millions of dollars for useless outdated upgrade of mirage now and Rafale later.


Hari Sud (M.S., B. Sc., P Eng.) said...

I wonder what all these critics above would say about American F-35.This plane at $200 million a piece is built to fail and stay in the hangar most of the time.

A score of 57 out of hundred is low as detailed by a post above. I do not know how honest he was giving grades. He appears to be chip of old Math teacher in high school.

It is not obsolete technology nor it is copied technology like somebody else's military hardware being lionized in the press these days. It is Indian, imported but paid for and technologies India has mastered now for the future.

When F-16 C/D blocks came to service, nobody dared to say anything unpleasant although they behind scene were working to improve. Americans knew that F-16 C/D block is no match to MIG-29, hence they were working overtime to improve it. That is what is happening to LCA -1. The newer LC-II would be 20% better. The latter models would stay current with newer and newer technology.

My point here is that "have a bit of self confidence". Do not jump all over it. With its design and operation India has learnt a lot of new military technologies.

What most posts above are looking for a composite of Grippen /F-16 (later models)/F-18/Raffale/ etc. That does not exist. The forgoing is a typical General J.S. Bewoor's (former Army chief thirty years back) view point - that write specifications and performance requirement so miserable that equipment like that does not exist. That philosophy still exits in the minds of today's critics.

Anonymous said...

Dear mr. Shukla

I used F 35 as an example as it has presently third generation AESA radar and by the time Tejas MK 2 gets inducted it would have fourth generation AESA radar which is well ahead of anything flying I wanted to say you don't have to buy large quantities of F 35 as it is very expensive and all you need is one F 35 accompanying 4 to 6 Tejas and can do better job then 6-8 Rafale can do. I had lot of juniors who use to come up with fantastic solutions and I never ever ridiculed anyone in fact they did help me with a new dimension to the problem and helped to team to achieve success. Time would tell who is moron and my advice to ADA team keep up the good work and you would be insulted and ridiculed but at the the end of the day what you achieve is all yours and show the world you can have a better fighter that upgraded mirage at less the cost. I know the feeling when the plane you are working on crashes and there is sadness and gloom in the team and I had few occasion where I had to face that my hooray for the Tejas team that they could achieve it without any accidents.

Bye for ever


Jean Luc Picard said...

A conclusion based on a study and simulation by the US Navy about its conflict with the Iranian Navy revealed a startling fact. In the Straits of Hormuz, if the there Was to be armed action, the Iranians would deploy a large small lethal armed speed boats in a "swarm attack" on US Carriers and the escorting Surface ships. The US navy determined that the surface hips will not be able to successfully defend against a swarm attack a majority of times. And now are designing armed drone boats for fleet protection.

Similarily, consider the LCA Tejas not as a Strike fighter designed to operate in small numbers. But as a "swarm attack" aircraft designed to be operated on the basis of numerical superiority. Even a single F22 or Su 30 heavy class fighter may not engage a formation of 4 Tejas LCA armed with BVRs.

Being Light Strike Fighters, the Tejas (Mk 2) may be deployed in a force protection role serving as scramble fighters and escorts for Jaguars or Mirages on a deep strike mission. Aux Fuel Tanks needed for deeper range.

The order of Large Number of Aircraft can help fill up the gap between sanctioned and available Squadron strength. Economies of Scale will make room for quality control, cost effectiveness and enhancement studies.

Being purposely built as stablized easy to fly aircraft. Im guessing its easier to use for Air-Ground Ops. May eventually replace the ageing SEPECAT Jaguar.

In My opinion, The Strategy for TEJAS R and D folks NOW should be to , focus less on the platform and More on its Safety/Quality Control,features, armaments and user friendliness, so young and relatively inexperienced pilots can be easily and successfully be deployed on it.

There is no point making LCA into a super Jet , when we already have Su 30 and FGFA for that.

Th retest exaple is the armed Little Bird AH 6 Helicopter. Its got more fire power than a ALH Dhruv or maybe even Armed Rudra.

Tactics is best left to IAF Brass.

The above is only my humble opinion.

Anonymous said...

You should invite someone from another blog/periodical to comment on this. Preferably from a non-Indian perspective. Now, I do not know of any such foreign blog that can do justice to the subject. But, presumably you do.

Air Cmdr. R said...

There are some genuine points in Timbaktoo's suggestion.

1. LCA needs (must) to have canards and better air-inlets like Gripen-NG. It also needs some lengthening at the front.

2. Wheels will have to go in the wings. Wings need more surface area and the wingtips need improvement.

3.Brakes need carbon fiber lining with gaps to reduce the heat build up.

4. Angle of Attack has to improve, preferably about 30 degree would be better.

5. All these will help improve the weapon load and fuel capacity.

6. ADA has to put the AESA radar, even 3rd generation one, in the nose cone. I don't see why they are refusing to think about this?

7. The naval version has to come fast. As PS said, it was a bad strategy to go from air version to naval version. However, it was first time, so it can be condoned.

8. A project approval for AMCA has to begin now. It will take more than 10-15 years to develop it but this corrupt government is sleeping on it.

We need air-revolution. As Shukla rightly said once, "A hawk with borrowed wings is not good at all."

Parthasarathi said...

Dear All,
Moderator has asked your honest opinion. But many of you are busy of criticizing others' opinion. If you have nothing to write then please clear off this forum. Mr. Hari Sud , no body has asked your unwanted opinion " A score of 57 out of hundred is low as detailed by a post above. I do not know how honest he was giving grades. He appears to be chip of old Math teacher in high school." on me. What is your problem ? Please refrain from this type of personal attack. Moderator please don't publish the comments which are criticizing others.

victor raj said...

First of all its an achievement for India. Comparing an aircraft with others will not do justice. Tejas is tailor made to suite Indian conditions and our necessities.

Tejas when it gets FOC, will be comparable to MIG27. Avionics and software wise it will be equal to any other 4.5 generation aircraft.

It is more than enough and cost effective to provide normal service sorties, where we don't want to waste putting a heavy fighter like SU30MKI. It will save a lot of money for IAF.

I will rate it below MIG-29, hardware wise.

Anonymous said...

@ Jean Luc Picard

Little Bird AH 6 Helicopter has more fire power than HAL Rudra, Seriously???

What did you smoke?

And HAL ALH Dhruv is a utility helicopter and you comparing with armed variant Little Bird AH 6.

suman chakraborty said...

Tejas aircraft, as it is today, should not be trashed, but finetuned by putting together the expertise of all the stakeholders - the indegeneous defense industry, the scientific community as well as the most important one - the users - the defence services. The expertise of the established private players like Tata Power, L&T, etc. should also be harnessed considering that a project of this magnitude is utmost importance to the nation. The quality and effectiveness of the finished product can always be improved in a phased manner. The induction of Tejas in substantial numbers is highly essential to overcome the gap left behind by the retirement of the Mig 21s.

Unknown said...

As commented in quite a few posts before mine I second the opinion that Tejas' position in the IAF's fleet with respect to optimum operational capability utilisation will be as an interceptor/air defence(fleet defence)/tactical strike (Close Air Support). To elaborate it could act as fighter support for a strategic strike aircraft like the Jaguar or Mirage and can be used as a decoy during such missions. Compared to the Gripen its combat radius isn't much (currently) but where it pips the Gripen is max speed (with afterburner) and thrust to weight ratio, hence an interceptor's role is where it can do justice in its current configuration. Also I agree that its Centre of Gravity needs to be shifted up front which can be done by adding armour, interior fuel tanks up front and an extra cannon this can be configured for CAS just like the A-10 Thunderbolt. Once the Naval LCA is operational it can fulfill the roles played by both F-14 Tomcats & Harriers, which are fleet defence and tactical strikes prior or during amphibious operations. Another role could be for sister to sister inflight refuelling. Also once there is advancement in technologies it could be fit EW pods and again can be used during strategic strike missions to jam enemy SAM/radar stations.

Well whatever operational role Tejas is assigned it is a piece of work every Indian must be proud of , yes it has had its hiccups but it represents the temerity of the Indian aerospace industry which is in its infancy but displays abilities that are not to be taken lightly. Jai Hind

axe said...

The question is ... what was the LCA primarily intended for?
Air defence with some ground attack capability and vice versa? Where was the LCA slotted to fit in the IAF scheme of things viz with the Su-30MKI and Rafale?
And does it fit in? That will be the answer.
It will be an operational work in progress for some time and will evolve into a mean fighting machine while newer platforms for future war scenarios will be developed in tandom.

Anonymous said...

With apologies to Nawaz Sharif, let me say "Hawa main udta hai(!!), bum girata hai, door door jaata hai(!!)". :D

Now where is my prize....

axe said...

Tejas ... a clarification from DRDO, HAL & ADA
Why have they termed IOC as Initial Operational Clearance while the rest of the military aviation industry calls it Initial Operational Capability?
Is there something we don't know or are trying to hide via an acronym loophole?
Tejas is a path breaking project and those involved will do well to keep within prescribed norms. We don't need the world's ridicule to belittle such a momemtus achievement.
Also ... indigenous this .. indigenous that .. enough already! Why do we have to announce so! Why this complex? We are developing good technology .. the world recognises that. Nevermind that certain developments are with clandestine help from friends .. the world recognises that too. So what? Just build it and build it well. The world will know it is Indian. Microsoft or Apple don't call their products indigenous but we know it is American. Let Tejas and other developments also be known that way.

Abhiman said...

Tejas' range-payload specs are comparable to the MiG-29s in IAF's fleet. They are both capable of carrying > 3 tons of weapons payload on internal fuel alone. The combat-radius shall also be the same, because if the MiG-29 has twice the Tejas' powerplants, it also weighs twice as much.

Now the question arises, of what use is the double weight of the Fulcrum and its double engine power? Especially when its conventional range-payload capability is the same as that of Tejas ?

What were the Soviet designers thinking ?

The answer lies in the fact that a MiG-29 can carry nuke weapons under its belly (though IAF ones aren't configured to). Typically, these are very heavy and can't be carried under Tejas' belly.

So, leaving aside nuke delivery Tejas is comparable to IAF's MiG-29s in the delivery of conventional weapons. It must be able to undertake Air-superiority missions inside Pakistan and Tibet. It can even escort Su-30 MKIs in their surgical missions deep inside Pakistan and Tibet.

straight_curve said...

The development of systems such as an aircraft is an evolutionary journey and in this context, what we have achieved with Mark- 1 is undoubtedly a momentous milestone to take pride in. At the same time, a comparison of Mark-1 with its competitors may end up giving a different feel but as long as progress is being made, I believe we are on right track.

The other important aspect which must not be overlooked is the possibility of Tejas being in the air forces of the many of third world countries to say the least. Some of you might have heard about the 1st flight of “Scorpion” , a tactical twin engine aircraft which was developed by Textron group. The Scorpion is being looked at replacing the much expensive aircrafts for roles/missions for which Scorpion is cost effective and aptly serves the mission requirements.

Why can’t Tejas be marketed as a low cost , sufficiently capable combat aircraft to the world with smaller pockets? To develop a successful aerospace industry, one must export….Assuming a good export success story of Tejas, one can be hopeful of a ripple effect on other domestic programs including future versions of Tejas. Sweden, US, Russia, UK are testimony to this.

Anonymous said...

I think its will be a mistake if IAF does not adopt the aircraft fully , they need to plan for atleast 400 fighters going into Mark II config otherwise it will be wasted effort.

Nishant Pathak said...

How about using the tejas mk1 as a close air support aircraft? The Americans tried converting the f-16 to an "A-16" by adding armour around the cockpit , strengthening the wings for a higher load and adding 2 additional gun pods. The a-16 never saw the light of the day as the army's current a-10 was extended. But a CAS version of the Tejas might work in India. (And also since we have no dedicated CAS aircraft presently in service) This version need not have a high power to weight ratio or higher angle of attack (Common complaints of Tejas). For CAS operations what matters is low velocity manouvers which I understand Tejas excels at.

Anonymous said...

The way I sum it up is we are definitely hypocrites.We compare Tejas to Gripin and so on and so forth. For most Tejas and Griping actually fall in the same category. Tejas definitely needs a more powerful engine. I suppose the money we spending on the Rafale could have been better utilized.
Consider our requirements. Pakistan has JF-17 and China has J-10. I think I would have been better if we would order 100 mk1 and 200mk2 to our inventory instead of the Rafale.
The concern only remains will HAL be able to deliver all.
No doubt that Rafale is superior to the Tejas but with improvement in Avionics and Radar systems (AESA Radar) it can give any fighter a run for its money. The apt of shooting a fighter jet is not just with the better aircraft, it is both the aircraft and pilot awareness.
Now don't run Tejas on the same boat as the Arjun Tank. Ordering 120 tanks and 120 fighter jets is a world of a difference. 120+ tanks can be made in a year. 120 jets will definitely take 8-10 years. Another thing is I think the airforce is right in its choice to take the number of MK2 required. However they could have managed a total of 200 Tejas.


100 mk1
100 mk2

The reason why we choose to take the Rafale is the Technology that comes with it. It will help us with the AMCA. In terms of the super cool gizmos in it.

My idea of IAF requirements should be:

300 - Su30 mk1
200 - Tejas
200 - FGFA
125 - Jaguars
110 - Mirages and Mig 29

The money spent on the Rafale can be better utilized to equipt the other defense divisions.

$4 billion - 12 kilos subs (immediate gap fillers - Russians can deliver subs quick)- This would be in addition to project 75I, which in broad words could be reducted to 4 subs - preferably Scorpenes as we have them already.

Army needs guns

$2.5 billion - 814 truck mounted guns
$400 million - 400 odd pinakas

and upgrade of all M46 130mm guns to 155mm 45 cal.

Another thing that comes to my mind is why scout for a gun when we can licence make the Bofors. I know the barrel burst but it is not impossible to rectify.

I know I have deviated from the topic but I think we need better use of resources and dedicated acceptance and mass production of Indian made products.

The army has definitely been the worst in terms of accepting Indian stuff. An attitude that requires must change.


Anonymous said...

@Mr. Timbaktoo,
1. Tejas has one of the largest static margins with its mean tinme to double amplitude being 200 ms. I think that I read somewhere that wobble is being faced at high speeds, but I can't confirm that either. But according to their studies from sea level trials, they found that wave drag was their biggest problem. So they are trying to smoothen all notches on the area curve. You must have read about the nose plug in Mk2. You might have also seen the smoothening along the APU intake and the trailing edge extension on LSP-7 and LSP-8. They are also redesigning the pylons with sharper leading edges. I was wondering what other things were you speaking of when you said "The shape of the front as well as back of the body around the wings be changed as per the wave-patterns".
2. The wing design (without the levcon) shows increase in CL till 35 degree AoA. They are seeing the cliff in CYM and CRM at 25 degree, that is why they are limiting AoA testing to 24 degrees right now. But they have significant rudder authority till 30 degree, So they are thinking of increasing AoA to 26 degrees by using artificial stabilization in yaw.
3. You might know that initially many configurations for LCA were studied including those with canards. They were discarded for the current configuration. So I don't think that they would go back to the canard configurations. Having said that they have found that the Levcons are giving them better L/D and they are thinking of making this part of the IAF version as well in order to meet the STR requirements.
4. I wouldn't go for the Gripen NG configuration for the MLG. They did not magically increase internal volume. Those large fairings at the wing body joint aggravates the wave drag problem. In stead I would go for a Mig-21 kind of solution, where the wheel is accomodated within the fuselage and the rest of the structures are accomodated in the wing. I will take whatever extra internal fuel that gives me. (Going by the models of Mk2 displayed till now, they pushed the MLGs a little more outward, but have still retained the original configuration from Mk1).
5. I don't think the IAF has the time to wait for Mk2 with a redesigned wing for extra weapon load and stations. Given the time restrictions, multi-rack pylons would do the trick, as the cummulative payload capacity of pylons od Tejas is more than the maximum payload that it can carry.
6. I would not like to increase the payload of Tejas Mk2 by a lot. Gripen NG fully loaded out is fairly restricted in its flight. It makes sense for lesser airforces which don't have medium-weight category fighter air craft. This is not the case with IAF which can afford to have efficient light, medium and heavy aircraft.

Indranil Roy

Anonymous said...

Colonel Shukla,

Thank you for your great write ups till now. I am really looking forward to your write up on Tejas post IOC-II. I had refrained from writing anything here since you had solicited comments from "from visitors with strong experience in design and operations", and I am just an enthusiast. Nonetheless, here are some of my questions which are hitherto unanswered.

1. They were studying using the MLG doors as air brakes. Any developments on the same.
2. When can we expect to see the reshaped pylons. Are they planning to retrofit the LCA Mk1 types with Levcons (they were studying this possibility) for meeting the IAF ASR regarding sustained turn rate(STR)? Will Mk1 be able to meet the ASR regarding the STR with these changes or will we have to wait for Mk2 with its more powerful engines.
3. Many models of LCA show the inboard pylon to carry 2 1000 lb bombs in tandem. However, I have never seen an LCA fly with this configuration. Can the LCA do the same?
4. Currently supersonic 800 ltr external tanks are being designed/fabricated. We will see them by FOC. What about 1200 ltr tanks?
5. Will the Mk1 planes have co-cured co-bonded wing for lesser weight. They were also trying to reduce the weight by converting the slat doors, casing & mounting of LRUs and rear fuselage bulkheads and pylons into composite materials. Have any of these been achieved?
6. For increased maneuverability throughout the flight they were thinking of introducing an active fuel proportioner for better C.G. management. Any developments in this front?
7. Are the issues related to the toe-touch during ejection resolved since AI'11?
8. Has the minimum chute jettison speed reduced from the 40 kmph identified at AI'11?
9. In the last high-altitude tests, there were problems with the engines. Have suitable modifications been made?

Thank you.

Indranil Roy

Broadsword said...


Your proposed re-design would make the Tejas a medium fighter from its current light fighter class. I'm sure you know that there are advantages in being a multi-role light fighter, even if it does not have some of the stuff that heavier fighters have.

Also, for Heaven's sake, what is this "balance" that you are trying to achieve?!! You have forgotten that the Tejas has been designed to be aerodynamically unstable.

You over-estimate the 414's power output!

Broadsword said...


I see that you've made a serious entry for the silver star!!

Broadsword said...

@ Anonymous 12:05

You're thinking in the right direction... :-)

Broadsword said...

@ Anonymous 13:32

Is your name Ajai Shukla?

Broadsword said...

@ Anonymous 15:05


Broadsword said...

@ Stratgenius

Ha Ha. While they're at the DA's office, you don't think they could free Devyani Khobragade, if they have some spare time after liberating Tibet?

Broadsword said...

@ Jean Luc Picard

Some very good points. Agree with you in many respects.

Broadsword said...

@ Air Cmde R

Air intake redesign can only take place for the Mk II. For now, it would be worth looking at whether the Mk I serves an operational purpose.

If that is so, the line can produce more Mk Is to replenish the dwindling squadron numbers, even as the Mk II is completing design.

You don't think so?

Broadsword said...

@ Abhiman

You're correct, except for your recommendation that the Tejas could escort the Su-30MKI on strike missions.

The Su-30MKI is big and powerful enough to carry a bomb load, air-to-air missiles for its own defence, and also my aunt's suitcase to be handed over in Lhasa.

That's what multi-role is.

Broadsword said...

@ Indranil Roy

Thanks for your great posts. You are modest. Your expertise is greater than most of us.

Can't comment on ongoing design thought and, in some cases, I simply don't know. But here are some answers to some of your questions.

Levcons. You might see them on the naval Tejas.

STR. Let's see how close they come in flight testing during 2014. The envelope is still being expanded in testing. They could very well prove 26 degrees in AoA. That would mean flying to 28 degrees.

Supersonic 1200 tanks will be tested.

No co-cured bonded wings now. Design has been frozen for manufacture.

Active fuel proportioner: already there.


Anonymous said...

Thank you.

Great nuggets of information. Did not know that there is a "might" involved for levcons related to the Navy version.

Indranil Roy

Abhiman said...

Col. Shukla, good to know that you agree that Tejas Mk.1 can undertake Air-superiority missions inside Pakistan and Tibet.

Tejas Mk.2 shall be equivalent to Gripen NG since both shall use the GE-F414 engine and have increased fuel capacity and payload capacity.

Again, Gripen NG cannot carry nukes, but its conventional range-payload specs should compare well with Rafale, Typhoon and F-16 E.

Now, the Ra-Fail, Typhoid and F-16 all have 150 kN of powerplant(s), and can carry upto 9 tons of conventional warload. So, why did the IAF also invite Gripe-water in the MRCA sweepstakes ? Gripe-water has just 108 kN powerplant and can carry just ~5.5 tons of external load.

Answer : Don't go by the fables of 9 tons max. weapons payload of Ra-fail, Typhoid and F-16 E. With that, they can just take-off, do a parikrama of their base before their fuel runs out. The real interpretation is that they're hardened to carry nukes or Brahmos-like hardware under the belly hardpoint.

This Herculean task can only be done by the F-15 Strike Eagle, and the Su-30. Nobody else.

Question 1 : Now, IAF never specified that the MRCA should be able to carry Brahmos or nukes. So, why was the Rafale chosen ? After all Gripen was the cheapest, hai na ?

Question 2 : Even if Gripen failed some initial tests, Tejas shall surely pass all those tests after FoC. And the Tejas Mk.2 shall be even better than Gripen NG.

Question 3: So, why doesn't IAF choose Tejas Mk.2 as the MRCA ?? Instead of wasting money on Rafale, why doesn't it work together with ADA to expedite Tejas Mk.2 ? It can even invite Reliance if it wants. They'll be happy as long as they get money, whether by Rafale or Tejas Mk.2, Mukesh Ambani won't care.

Anonymous said...

So who won what star?

Anonymous said...

My assessment of the Tejas program from a broader, end user prospective:

1. The overall airframe design is the latest from the 1980s, not the 2nd decade of the 2000s. Draws much from the Mirage 2000 and MiG - 27, both designed in the 1970s.

2. Easy to blame this on the specs as given by IAF, but then these specs were given in the early 1980s. The programme shouldve had a Sunset Clause, so that if the first prototype wasnt ready by a decade or so from commencement, cancel it.

3. The private sector shouldve been involved to a higher degree, with DRDO providing research and technical support. If groups like tot eh Tatas are good enough for Sirkosky to enter JVs into, L&T can design n build specialised frame, etc, a better job wouldve been done on this.

4. With the global aircraft majors now exploring technologies such as the BAE Taranis, N-Grumman X-47B, etc we should not be spending money re-inventing the wheel but encouraging govt and private corporates to design the next gen of systems. a JV like that for Brahmos would be a great way to do this.

Finally, im sorry to say this, but i think we should take ACM Tipnis' advise- the Tejas should be sent from the drawing board to the meuseum. A good effort, but not worth risking pilots and operations on.

Anonymous said...


I guess this is really late, I have to share this for keeping the record straight.

Active fuel proportioner is not going to be incorporated in LCA Mk1 (don't know about Mk2). They are quite happy with the passive fuel proportioner itself.

Thank you.
Indranil Roy

MM said...

sir can any one tell me actual projected top speed of LCA MK1, and achieved top speed of LCA MK1.

thank you.