HAL Tejas | Updates, News & Discussions-[Thread 2]

[MirageBlue]

Levcons are out of question now for any fighter in dev now. Atleast for now. Closed coupled canards are the system design.

Yes, it is extremely unlikely. However, the N-LCA Mk1 with LEVCONs has been tested on the carrier and works. So while it is very unlikely, it cannot be completely ruled out.

The air force version is single engine and navy is twin engine. both have caranrds.

TEDBF may or may not have canards. We don't know as yet. It is an ADA design and concept studies were on-going.

The renderings of ORCA (viz. the IAF version of TEDBF) that we have seen so far have come from HAL, which is pro-actively trying to interest the IAF in a twin-engine Rafale class fighter after the single engine MWF which is a Mirage-2000 class fighter.

 

[Nilgiri]

<sigh!>

Is this some kind of dick-measuring contest?



If you were not so much in love with your detective abilities, you might have noticed that this is content from a third-party article. There is no point in disputing it; the author is not present, and he will not answer questions.

I am accepting nothing, just showing you what has been presented. If you don't like it, feel free to conclude whatever you will.



The article explicitly mentions that there is likely to be saving in weight due to aeroframe optimisation. You can't sit on your chair in front of a system connected to the Internet, and decide that nobody else knows anything.

Joe Joe Joe ... not worth it.

2020 account, 17 posts = unless proven otherwise.

 

[Armchair]

The air force version is single engine and navy is twin engine. both have caranrds.

Thanks for the reply!

 

[Dash]

Yes, it is extremely unlikely. However, the N-LCA Mk1 with LEVCONs has been tested on the carrier and works. So while it is very unlikely, it cannot be completely ruled out.



TEDBF may or may not have canards. We don't know as yet. It is an ADA design and concept studies were on-going.

The renderings of ORCA (viz. the IAF version of TEDBF) that we have seen so far have come from HAL, which is pro-actively trying to interest the IAF in a twin-engine Rafale class fighter after the single engine MWF which is a Mirage-2000 class fighter.

The article I think published on DDR ruled out levcons, but adding levcon is not much of a challenge since it adds to lift and stability to the fighter while landing. (Tailess deltas cant use flaps). But again the deltas themselves are a very stable design.
But if they add then its totally alright. But I havent seen a config so far.

Regarding the ORCA, I believe HAL cant go it all alone with that design unless they have a proper design agency like ADA or a foreign partner. Other than that it all looks good.

 

[MirageBlue]

The article I think published on DDR ruled out levcons, but adding levcon is not much of a challenge since it adds to lift and stability to the fighter while landing. (Tailess deltas cant use flaps). But again the deltas themselves are a very stable design.
But if they add then its totally alright. But I havent seen a config so far.

Regarding the ORCA, I believe HAL cant go it all alone with that design unless they have a proper design agency like ADA or a foreign partner. Other than that it all looks good.

I would consider the possibility of LEVCONs on TEDBF to be very remote, given that they do some of what canards do, but are not functional during maneuvering and hence canards are far better.

Since MWF is getting canards, there is a good chance of the TEDBF getting it too, but clearly ADA thought that there is great value in going with stabilators and vortex flaps in the Naval-LCA Mk2 design as shown below.

Theoretically, they could just work on adding an additional engine to this N-LCA Mk2 design and call it the TEDBF.

Or they could work on adding a second engine to the MWF and making it a larger design, to make it the TEDBF.

Basically, a lot of concept studies and work will be on-going at ADA currently before a TEDBF design is frozen.

I agree, HAL cannot build an ORCA on it's own and it shouldn't. ADA is the design agency with the expertise on fighter design and HAL supports it with expertise in various systems design and integration.

I firmly believe that ORCA will be an Air-Force variant of the TEDBF with the necessary optimizations and modifications that Air Force designs have compared to Navy designs. HAL will be able to manage that with ADA involvement. Grp Cpt HV Thakur kind of confirmed that on Twitter as well, stating that ORCA is basically an Air Force variant of TEDBF in order to increase the number of units and make the program feasible financially. It doesn't make sense to spend a billion $ on TEDBF for 57-60 fighters alone. Add the possibility of 100+ IAF orders and then the program becomes worth pursuing.

 

[no smoking]

<sigh!>

Is this some kind of dick-measuring contest?

Dick-measuring contest? Against what? I asked a question using 2 India designs. So I am measuring Indian dick #1 vs Indian dick #2.

If you were not so much in love with your detective abilities, you might have noticed that this is content from a third-party article. There is no point in disputing it; the author is not present, and he will not answer questions.

I am accepting nothing, just showing you what has been presented. If you don't like it, feel free to conclude whatever you will.

Unlike you who is defensive for India's everything, I am questioning what I think is not right, no matter it is Indian fantasy or Chinese fantasy. If you can't deal with other people's challenge, maybe you shouldn't put it on a public forum.

The article explicitly mentions that there is likely to be saving in weight due to aeroframe optimisation. You can't sit on your chair in front of a system connected to the Internet, and decide that nobody else knows anything.

Structure optimisation is not magic, its weight reduction effect has limitation. Just look at the data of Gripen E in the paper:
1. 0.55m longer;
2. 0.36m lower;
3. wing area is 7.4m2 less than Tejas Mk2.
We can say that Gripen E is a jet with the similar size as Tejas Mk2. However, this latest Gripen variant is 1 ton heavier than latter. Doesn't Sweden know how to optimise their jet structure. Or once again, someone is just too optimistic about their capabilities.

Joe Joe Joe ... not worth it.

2020 account, 17 posts = unless proven otherwise.

I guess you are the best follower of fanboys whose post numbers are always on the top.

 

[Joe Shearer]

It's a mistake.

The LCA Mk1 is ~6500-6600 kgs empty weight
The LCA Mk2 (MWF) target empty weight as per the info released at Def Expo 2020 is ~7800 kgs.

The reason I say 'target' empty weight is because as we've seen with the Gripen NG program that eventually became the Gripen E/F program, the final empty weight can be higher. The Gripen NG was advertised as having an empty weight of 7000 or 7200 kgs. When it was actually developed as a production fighter, the new empty weight came out as 8000 kgs.



No canards for the AMCA. That's for sure. Trapezoidal wing with large stabilizers is the configuration chosen.

However, we don't know yet what the concept studies for the TEDBF will result in;

1) TEDBF with close-coupled canard and delta wing like the MWF
2) TEDBF with delta wing and stabilators like the single engined N-LCA Mk2 (which was dropped for the TEDBF)
3) TEBDF with delta wing and LEVCONs (like the N-LCA Mk1)

Tejas twin seater in front of Mehrangarh fortress, Jodhpur.

Tejas twin seater in front of Umaid Bhavan, Jodhpur

Image credit Deb Rana

Not entirely a mistake.

I agree with you regarding the actual measured weight of the developed Mk1 being 6600 kgs whereas the target weight of the Mk2/MWF is set at 7000 kgs according to the Defence Review article (7800 kgs according to the figure you have reported from the announcement at DefExpo 2020). Defence Review reported the Mk1 weight itself as 7040 kgs, so there is confusion created when it goes on to say that the Mk2 may be 7000 kgs, or 40 kgs lighter.

That, as an inter se comparison, is one thing; clearly, either we take the Mk1 weight as 6600 kgs or as 7040 kgs. It depends on which weight we take; between the 6600 kgs actual weight, and the 7040 kgs of reported weight from the Defence Review, there is a gap of 440 kgs., and that can accommodate a lot of changes. There is another even larger gap between the 6600 kgs actual weight and the target weight of 7800 kgs reported from DefExpo., a gap of 1200 kgs.

Then the question is whether or not the proposed changes and modifications will use up the entire gap that we see here. I hope you will agree if we list the major weight components of an aircraft as follows:

1. Airframe
   
2. Engine
3. Landing gear and drogue parachute
4. Sensors
5. Instrumentation

Let us leave aside the airframe for a moment.

The difference between the F404 and the F414 is 75 kgs (1,110 kgs for the 414, 1,035 for the 404); there should be 0 difference in landing gear and chute; we are left with the weight of sensors, and the need to accommodate additional sensors if any, and the weight of instrumentation. The weight of instrumentation has steadily gone down over the years; we may find a credit balance for the instrumentation, if anything. It then remains to assess the weight of additional sensors, assuming existing sensors are the same weight, except for the weight of an AESA radar in place of a PESA radar.

We have the following programme suggested to us:

1. AESA radar with integral Unified Electronic Warfare Suite
2. Dual colour Missile Approach Warning System
3. Larger MFDs
4. Digital Flight Control Computer hardware upgrade
5. Network Centric Warfare 'capability'

These are picked out from the passage below.

MWF will be a multirole aircraft capable of carrying R-73 (and possibly ASRAAM and Python 5) CCMs, Derby and Astra BVRs, 250 kg and 500 kg dumb and laser guided bombs, heavy precision glide bombs of standoff ranges, India’s New Generation Anti-Radiation Missile besides lightweight cruise missiles, including SCALP and Brahmos-NG. It will sport an active electronic scanned array (AESA) radar with an integral Unified Electronic Warfare Suite (UEWS) and a dual colour Missile Approach Warning System (MAWS) along with an upgraded glass cockpit with larger MFDs. The Digital Flight Control Computer hardware will be upgraded to the latest standard. Over the years, flight control actuators have been successfully indigenized. MWF will feature these Indian actuators, which is another significant achievement. It will also feature an enhanced Network Centric Warfare capability with seamless integration with various offensive and defensive systems of the Indian Armed Forces.

None of these five are likely to consume the entire weight gap between the Mk1 6,600 kgs and either the 7,000 kgs of one report or the 7,800 kgs of the DefExpo figure.

I will explain in a following note why looking at the increased dimensions of the airframe, the length, height, wing span and wing area leads to errors of estimation; these increases do not correlate to the weight in a uniform manner.

 

[Dash]

I would consider the possibility of LEVCONs on TEDBF to be very remote, given that they do some of what canards do, but are not functional during maneuvering and hence canards are far better.

Since MWF is getting canards, there is a good chance of the TEDBF getting it too, but clearly ADA thought that there is great value in going with stabilators and vortex flaps in the Naval-LCA Mk2 design as shown below.

Thank you for that. Looks good for Mk2. We need to look at TEDBF final design.

Theoretically, they could just work on adding an additional engine to this N-LCA Mk2 design and call it the TEDBF.

I am not aware of Mk2 but Mk1 had issues with the landing gear and that significantly reduced the aircraft performance. So adding and additional engine to Mk2 without addressing the mentioned issue will not bear fruit. But I would trust the guys who are doing it.

Quoting from DDR.

http://delhidefencereview.com/2019/...-to-the-twin-engine-deck-based-fighter-tedbf/

To handle the intense additional stresses likely to be experienced during carrier landings, the undercarriage of the IAF version had to be greatly strengthened, even though the overall airframe was perhaps not modified to the same degree. However, this decision to not substantially modify the baseline LCA airframe led to a NLCA Mk1 design where the strengthened landing gear would ‘sprawl’ under its airframe. This in turn prevented the carriage of external fuel tanks ( or indeed any ‘heavy’ weapons) on the inboard weapons stations of the NLCA Mk1’s wings. This meant that only the centerline and mid-board weapon stations could be used to carry drop tanks, thereby reducing the payload flexibility of the design.

As regards to HAL with ADA as design agency is good but someone from the top, like HV Thakur said, need to actually put the things into perspective in order to get where we ant to.

 

[Andhadhun]

 

[MirageBlue]

I am not aware of Mk2 but Mk1 had issues with the landing gear and that significantly reduced the aircraft performance. So adding and additional engine to Mk2 without addressing the mentioned issue will not bear fruit. But I would trust the guys who are doing it.

The issues related to the location of the Main Landing Gear on the Naval LCA Mk1 were to be addressed as part of the Naval LCA Mk2 single engine design. And it was taken care of in the design.

It was done by pushing the wings out farther- basically the Naval LCA Mk2 design's fuselage was made broader, to accomodate more fuel as well as to push the wings out farther, so that the inboard wing pylons were no longer interfered with by the Main Landing Gear.

 

[Dash]

The issues related to the location of the Main Landing Gear on the Naval LCA Mk1 were to be addressed as part of the Naval LCA Mk2 single engine design. And it was taken care of in the design.

It was done by pushing the wings out farther- basically the Naval LCA Mk2 design's fuselage was made broader, to accomodate more fuel as well as to push the wings out farther, so that the inboard wing pylons were no longer interfered with by the Main Landing Gear.

But it still had the same engine. A heavier body was going to be difficult for the GE engine. I seriously believed LCA as a design was not meant for the navy. The 90-100 odd F414 EPE was lying in order stage (was it delivered ever?). We should have done a complete fuselage redesign from the beginning but I believe we were just curious to see the "carrier landing" testing.

 

[ziaulislam]

But it still had the same engine. A heavier body was going to be difficult for the GE engine. I seriously believed LCA as a design was not meant for the navy. The 90-100 odd F414 EPE was lying in order stage (was it delivered ever?). We should have done a complete fuselage redesign from the beginning but I believe we were just curious to see the "carrier landing" testing.

ofcourse its not..it just milking money..
if HAL is serious about it it should design a twin-engine around the geF414 and that too if the carrier has catapult launch system

 

[Dash]

ofcourse its not..it just milking money..
if HAL is serious about it it should design a twin-engine around the geF414 and that too if the carrier has catapult launch system

Well what you said is not true. Its never milking money, a scientist is the last person to milk money from govt that too when he is working for it.

About twin engine. Thats not necessary for a ship borne fighter, at least now a days. Single engine will do too. Having said that, the areas where we lacked is the way our PSUs are being run. Its a classic case of program mismanagement and nothing else. Everything else is just thre.

 

[Lord Of Gondor]

The 90-100 odd F414 EPE was lying in order stage (was it delivered ever?).

Yes, ADA has around 14 GE F-414 INS6 engines for the Mark-2.
Orders for the remaining will be given by HAL once GoI signs the contract with HAL for the Mark-2.

 

[MirageBlue]

But it still had the same engine. A heavier body was going to be difficult for the GE engine. I seriously believed LCA as a design was not meant for the navy. The 90-100 odd F414 EPE was lying in order stage (was it delivered ever?). We should have done a complete fuselage redesign from the beginning but I believe we were just curious to see the "carrier landing" testing.

I think you've confused what I said- I said that the N-LCA Mk2 was re-designed by widening the fuselage and pushing the wings out.

N-LCA Mk2 was to use the F-414-INS6. And with 98 kN of thrust, it should've been able to meet the payload requirements of the IN, for a single engine fighter.

Carrier trials were not just out of curiosity. It required a lot of effort and quite a bit of money to be spent on it. It is genuine data gathering and a wealth of experience, which nobody can get without doing it themselves. The carrier trials of the N-LCA Mk1 have now convinced the Indian Navy that a twin engine TEDBF is genuinely do-able and not just another science project.

ofcourse its not..it just milking money..
if HAL is serious about it it should design a twin-engine around the geF414 and that too if the carrier has catapult launch system

If anyone or anything is milking money it is foreign imports that cost thousands of crores of rupees and provide employment and business to some foreign firm with not much attendant technology gain for India.

Providing money of a few hundred crores to design and develop a local fighter is not called milking money- it is an investment in a local aerospace eco-system without which India would forever be importing fighters from abroad. That is how ALL nations that are self-sufficient in aerospace work- their govt. spends money on local programs.

BTW, ADA is designing a twin engine TEDBF naval fighter for the Navy around 2 F-414-INS6 engines. And no, the 2 carriers the Navy has are still going to be STOBAR and the TEDBF will also be a STOBAR fighter, like the MiG-29K.