Tejas Mk.2: News & Discussions - 25 February 2018

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raghuk
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by raghuk »

Regarding the canard I think it is there more to provide the required instability(forward lifting surface). Without the canard the Mk2 would become excessively stable and not be as agile. Also it would lose the tag of being the most unstable aircraft ;)
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Indranil »

That is not the cause ;-). If they wanted to increase stability they could have just set the wing a little more to the front.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Cybaru »

Kartik/IR can you add your AI synopsis from 13, 15 and 17 on the front page? That way we can see the evolution.

I hope they redesign the undercarriage and how it is stowed to really free up more space in the body.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Indranil »

With respect to the AF version, they will elongate the MLGs slightly. That will allow them to carry LGBs on the centerline pylon. Other than that, I have not read or heard about any change. Why do they need to change the LGs? The MLG is covered using two doors. One in the front which is open when the LGs are extended. The second part which covers the wheel opens momentarily only when the MLGs are being extended or retracted. They stay closed during taxiing and take-off/landing runs to safeguard the innards against FOD.

There was talk about using the first door as the airbrake, but hat has since been dropped. This door is hinged at the front. If they make it side hinged, it will decrease the drag during both TO/landing and more importantly clear up space around the centerline pylon. LCA NAvy already has this door hinged to the side. It remains to be seen what is done for LCA Tejas Mk2.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by ramana »

ramana wrote:I think we can soon rename Tejas Mk2 as MCA.

As the quantity will be 201 and could be higher eventually, should get the name changed.
Until the Mk2 is given a new name and make it different than the Tejas, IAF will keep asking for more SEF/MRCA.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Rakesh »

+108 Ramana-ji.

Mk2 represents an existential threat to the SEF/MRCA contest. Thus the reason for the constant pushing of the SEF/MRCA. Anything to kill the platform.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by putnanja »

Indranil wrote:With respect to the AF version, they will elongate the MLGs slightly. That will allow them to carry LGBs on the centerline pylon. Other than that, I have not read or heard about any change. Why do they need to change the LGs? The MLG is covered using two doors. One in the front which is open when the LGs are extended. The second part which covers the wheel opens momentarily only when the MLGs are being extended or retracted. They stay closed during taxiing and take-off/landing runs to safeguard the innards against FOD.

There was talk about using the first door as the airbrake, but hat has since been dropped. This door is hinged at the front. If they make it side hinged, it will decrease the drag during both TO/landing and more importantly clear up space around the centerline pylon. LCA NAvy already has this door hinged to the side. It remains to be seen what is done for LCA Tejas Mk2.
Similar to the proposed NLCA-MK-II, it would have been good if they were looking at moving the LGs towards the wings freeing up more space in the center wingbox area to hold more fuel.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Indranil »

I have pondered on this subject for very long. Could the underwing-body join be smoothed out more. And can the MLG be retracted into this smoothened join. However, I don't think is it possible without making the LG more complex which will be counter productive.

What you are suggesting is a much bigger change. The structure of the fuselage and wings are tightly coupled with the MLG mounts. If you want to move the LG mounts to the wing or wing root, it will completely change the internal structure elements. This is will a very intensive process. This is actually one of the biggest learnings of NLCA Mk1. They wanted to retain the structure of the LCA. But this meant that LG now had to take most of the extra shock of deck landing instead of passing it for absorption on the entire structure. This made the LG complex and heavy. They have since solved it on the NLCA Mk2 design. The thing is: NLCA Mk2 is a bigger airframe (the same size as Gripen E). This will affect its performance. The AF LCA Mk2 will retain the smaller and nimbler profile powered by the same engine.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Kartik »

One question about airbrakes- since the Tejas Mk2 with canards is being studied, and it is to be a close coupled canard that will be powered by actuators, can't it be used as a an airbrake surface? the Gripen uses that solution to allow for reducing landing distances and it could be used in conjunction with the braking chute to ease wear on the MLG's carbon-carbon brakes.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Kartik »

I hope we see some image of the proposed Tejas Mk2 at this year's DefExpo. There are just so many questions in my mind about the kind of configuration being studied.
Last edited by Kartik on 07 Apr 2018 00:45, edited 1 time in total.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by ramana »

Sorry to interrupt but what is MLG? I get LG is Landing Gear
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Kartik »

ramana wrote:Sorry to interrupt but what is MLG? I get LG is Landing Gear
MLG- main landing gear

NLG- nose landing gear
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by nachiket »

ramana wrote:Sorry to interrupt but what is MLG? I get LG is Landing Gear
Main Landing Gear. The aft LG in a tricycle layout. The one in front is the Nose Landing Gear.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Indranil »

Kartik wrote:One question about airbrakes- since the Tejas Mk2 with canards is being studied, and it is to be a close coupled canard that will be powered by actuators, can't it be used as a an airbrake surface? the Gripen uses that solution to allow for reducing landing distances and it could be used in conjunction with the braking chute to ease wear on the MLG's carbon-carbon brakes.
I am pretty sure it will be. Not only can they work as airbrakes, but when do so, they also work like a spoiler which increases braking efficiency.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Indranil »

The payload requirements of the RFI posted by IAF is very interesting. Just 2 LGBs, + 2 BVR + 2 WVR + external fuel tanks is strike config. Well, LCA can easily do so. Similarly A2A missions is 4 BVR + 2 WVR + external tanks. Again well within reach. LCA should just develop some multiracks. First, carriage of 2 BVRs in parallel; and second: carriage of an LGB and a BVR on midboard pylon in an L config.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by nrshah »

Indranil wrote:The payload requirements of the RFI posted by IAF is very interesting. Just 2 LGBs, + 2 BVR + 2 WVR + external fuel tanks is strike config. Well, LCA can easily do so. Similarly A2A missions is 4 BVR + 2 WVR + external tanks. Again well within reach. LCA should just develop some multiracks. First, carriage of 2 BVRs in parallel; and second: carriage of an LGB and a BVR on midboard pylon in an L config.
Is not this for RCS measurement only. Basically 3 configurations. Clean, A2A and A2G configurations for which specific payload configuration has been stipulated. Clearly, IAF is understanding the brochure values are shit and have been looking for more realistic assessment. Having said that, the payload configuration looks like the standard one which they envisage in normal operations though the capacity may be more. Interesting is that they are looking for 10 hrs endurance with aerial refueling from medium birds which they are already practising on mki. Insights on their war tactics??
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by SaiK »

https://en.wikipedia.org/wiki/List_of_a ... y_aircraft

Code: Select all

MiG-21	Russia	Fighter	bis/Bison[1]		244[2]	
MiG-27	Russia	Ground attack	ML	  		84[2]	
MiG-29	Russia	Multirole	MiG-29UPG[3]  	66[2]
===================================================
Total: 													394
so, we need nearing 394 Tejas Mk2s. Perhaps the Mig 29s weren't considered for the "Tejas 324" project. :wink:
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Cain Marko »

Call me suspicious but I'm not too happy with the IAFs commitment to a future variant. I would have have preferred a commitment of at least another 100 birds at foc cum mk1a std.

This seems like kicking the can further discuss the road, and the all too predictable rfi for 100 mrca makes it all rather suspect.

But I could be wrong... I just hope the damn rfi never goes through, there are at least a few things that the babus can be thanked for....
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by JayS »

nrshah wrote:
Indranil wrote:The payload requirements of the RFI posted by IAF is very interesting. Just 2 LGBs, + 2 BVR + 2 WVR + external fuel tanks is strike config. Well, LCA can easily do so. Similarly A2A missions is 4 BVR + 2 WVR + external tanks. Again well within reach. LCA should just develop some multiracks. First, carriage of 2 BVRs in parallel; and second: carriage of an LGB and a BVR on midboard pylon in an L config.
Is not this for RCS measurement only. Basically 3 configurations. Clean, A2A and A2G configurations for which specific payload configuration has been stipulated. Clearly, IAF is understanding the brochure values are shit and have been looking for more realistic assessment. Having said that, the payload configuration looks like the standard one which they envisage in normal operations though the capacity may be more. Interesting is that they are looking for 10 hrs endurance with aerial refueling from medium birds which they are already practising on mki. Insights on their war tactics??
nrshah,

Apologies. I misread your sentence. Clearly I need some morning coffee. Please forget what I said. I cleaned up the posts as they are not needed anymore.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by JayS »

Indranil wrote:You are right sir. Frankly, I am a bit perplexed by Jay's confusion. He knows exactly how it will look like.
I just wanted to understand it clearly what you meant.

I am slightly disappointed. But I guess I know why ADA does not want to make canard as a pitch control surface. Perhaps they do not want the same issue that Gripen has faced. I still hope they extend Mk2 to 15m. If they think moving MLG out is too much work, that can be omitted. But I think lengthening significantly is absolutely a must given canard.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by vina »

JayS wrote: I still hope they extend Mk2 to 15m. If they think moving MLG out is too much work, that can be omitted. But I think lengthening significantly is absolutely a must given canard.
The Canard may NOT needed at all. There is a better way than canard for the fuselage plug which adds weight in front of the CG, making the plane more stable (canard generates lift there and unloads the nose).

Wait for my post on the Kaveri. I am typing it up and will post the link to the document. Canard will add drag. What I am proposing is ALL plus. No drag and "no penalty". All "enaam" onlee. Nice na?

Too painful, its been a looong time since I wrote any " papers" other than dishing out quick emails/notes /and of course ppt. My word processing skills are pretty rusted,I dont have too much time to spend on it. Old man RBose will of course sniff and claim that anything not typed out on Tex /LaTex or similar is not "genuine stuff". Will let that slide though.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by JayS »

vina wrote:
JayS wrote: I still hope they extend Mk2 to 15m. If they think moving MLG out is too much work, that can be omitted. But I think lengthening significantly is absolutely a must given canard.
The Canard may NOT needed at all. There is a better way than canard for the fuselage plug which adds weight in front of the CG, making the plane more stable (canard generates lift there and unloads the nose).

Wait for my post on the Kaveri. I am typing it up and will post the link to the document. Canard will add drag. What I am proposing is ALL plus. No drag and "no penalty". All "enaam" onlee. Nice na?

Too painful, its been a looong time since I wrote any " papers" other than dishing out quick emails/notes /and of course ppt. My word processing skills are pretty rusted,I dont have too much time to spend on it. Old man RBose will of course sniff and claim that anything not typed out on Tex /LaTex or similar is not "genuine stuff". Will let that slide though.
Canard is a done deal. Not a may be. That enables them now to increase length much beyond previously decided 0.5m. I hope they pluck that fruit.

BTW, canard may add some drag but it also takes out some elsewhere, in effect reducing total drag. A well designed canard config has lesser trim drag than non-canard config.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by vina »

JayS wrote:Canard is a done deal. Not a may be. That enables them now to increase length much beyond previously decided 0.5m. I hope they pluck that fruit.
BTW, canard may add some drag but it also takes out some elsewhere, in effect reducing total drag. A well designed canard config has lesser trim drag than non-canard config.
What are the dimension of the co-cured fin torsion box of the LCA ? What is it's thickness ? Any rough numbers? The area I can estimate roughly from pictures, but I need the thickness as well.

In any case, I think they will need to increase the tail surface area in MK2 if they are going to put a plug in front. The wetted surface area in front will increase and the front gets more stable in yaw and the rear will tend to yaw. So expect an enlarged vertical stabiliser.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by JayS »

vina wrote:
JayS wrote:Canard is a done deal. Not a may be. That enables them now to increase length much beyond previously decided 0.5m. I hope they pluck that fruit.
BTW, canard may add some drag but it also takes out some elsewhere, in effect reducing total drag. A well designed canard config has lesser trim drag than non-canard config.
What are the dimension of the co-cured fin torsion box of the LCA ? What is it's thickness ? Any rough numbers? The area I can estimate roughly from pictures, but I need the thickness as well.

In any case, I think they will need to increase the tail surface area in MK2 if they are going to put a plug in front. The wetted surface area in front will increase and the front gets more stable in yaw and the rear will tend to yaw. So expect an enlarged vertical stabiliser.
See if you can read the numbers in this paper.

https://nal-ir.nal.res.in/2659/1/jr_jasi_54%282%29.pdf

I think 200mm would be a good number for thickness, give or take some.

The fin was slated to be increased in height by 0.2m IIRC.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Kartik »

No Tejas Mk2 models at DefExpo 2018?
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by SaiK »

Was the Rs 800 crore requested for Mk. 2 sanctioned or it is still in the dark?
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Cybaru »

Pulling out some old posts from Navy Mk2, how have things changed? The navy mk2 was bigger than the mirage and a lot of work had gone into it. these posts are from the older thread (viewtopic.php?f=3&t=6964&p=1807763&hili ... s#p1807763)

Are we going to see mid section fuselage broadening which will lead to increased fuel capacity?
Thakur_B wrote:Good read on why LCA Navy Mk-1 has exceeded design parameters and design considerations of Navy Mk-2.

http://thumkar.blogspot.in/2015/03/lca-navy-succeeding-through-success.html
Success from Failure

Failure of an endeavor is often just a turning point on the road to success. Failure is never absolute; it can at best be defined as lack of success. Sometimes, failure can even be redefined as success.

The Indian Government sanctioned Full Scale Engineering Development (FSED) of Naval Light Combat Aircraft (LCA-Navy), capable of operating from an aircraft carrier, on March 28, 2003 with a PDC of March 27, 2010. Had the Indian Government defined LCA Navy as a technology demonstrator project, which is what it has ended up becoming, there would have been no doubt about the resounding success of the project!

As a technology demonstrator project, the LCA leaped out of doldrums when Navy Prototype 1 (NP-1) successfully executed its first ski-jump take-off at the SBTF in Goa on December 20, 2014.

NP-1 attempted the ski-jump after a 300-m roll in clean configuration presumably with full internal fuel. The safe take-off required 150 knot at a climb rate of 6.4 degrees. But, the aircraft bested the benchmark with a climb rate of around 11 degrees.

The flight also validated the hands-off take-off algorithm of LCA Navy's Flight Control Software (FCS).
Reason for Better than Expected Performance
Press reports on the better than expected climb performance of NP1 have been confusing. Here is simple and precise explanation.

The LCA's GE-F-404-IN20 engine needs be at 80% RPM for around 5-min for it to give assured peak thrust at full throttle. Since it's not practical for an operational aircraft to wait for 5 mins before take-off, ADA had factored in the lower than max thrust when calculating expected rate and angle of climb on leaving the ramp. The aircraft designers were pleasantly surprised when due to higher than expected thrust NP1 outperformed the conservative calculations.

It's now clear that LCA Navy Mk-1 could carry more weapons and fuel than initially thought.

At Aero India 2015, IDP Sentinel asked LCA Navy Project Director Commodore CD Balaji if the better than expected performance could result in the aircraft being operationally deployed on a carrier, were the LCA Navy Mk-2 project to be delayed.

"LCA Navy Mk-2 will not be delayed," said Balaji with a lot of confidence. "We are close to freezing its design, which has been simplified. The new design would be easy to implement."



LCA Navy Mk-2

Commodore Balaji's confidence was eye-opening - The biggest pay-off from the LCA Navy project may well be ADA's increasing confidence in its ability to tweak fighter aircraft design to squeeze out better performance. This is evident from the following

LCA Navy Mk-2 has been designed from the ground up as a Navy fighter, independently of Tejas LCA Mk-2.

The fuselage of the aircraft has been broadened and the wing roots moved outwards. As a result, aircraft design has been optimized for supersonic flight with perfect conformance to area rule. (Tejas LCA and LCA Navy Mk-1 do not conform perfectly to area ruling resulting in high supersonic drag.)

Mid section fuselage broadening allows undercarriage bays to be shifted outwards, allowing a simpler, straight and light undercarriage as in the Rafale.

Mid section fuselage broadening also increases fuel capacity.

That is three birds with one stone!
Indranil wrote:
disha wrote: Indranil'ji - request to check out the underbelly of A380 to get an idea of the underbelly of the NLCA-Mk2.
No 'ji' for me please.

I don't get the similarity of the underbellies. In the 380, the MLGs retract into the fairing attached to the fuselage. The MLG attached to the the wing retracts sideways into the fuselage fairing. In the NLCA Mk2, the fairings seem to be attached to the wings. The MLG retracts straight up into this fairing.

To me the idea seems like this. Look at the bottommost right picture. You can see how the the decrease in the crosssectional area of hump coincides with the increase in the area of the MLG fairing. The fairings themselves taper of (somewhat like Kuchemann's carrots) under the wing.
Image
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by putnanja »

Post upgradation Tejas’ Mark-2 to become a medium weight fighter
Aeronautical Development Agency, the design agency of the indigenous fighter aircraft programme, has finalised the systems and is looking to freeze the design of the medium weight fighter in a couple of months, a top scientist told ET. It is expected to have a maximum take off weight of 17.5 tonnes with an improvement of over 85% in weapons and payload carrying capacity to that of Tejas, light combat aircraft (LCA).
...
“The LCA was designed to replace the MiG-21aircraft, whereas the Mk-2 is being designed to replace the Mirage 2000,” Dr Girish Deodhar, programme director of ADA told ET. “It is being redesignated as a medium weight fighter.”

...
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by rkhanna »

putnanja wrote:Post upgradation Tejas’ Mark-2 to become a medium weight fighter
Aeronautical Development Agency, the design agency of the indigenous fighter aircraft programme, has finalised the systems and is looking to freeze the design of the medium weight fighter in a couple of months, a top scientist told ET. It is expected to have a maximum take off weight of 17.5 tonnes with an improvement of over 85% in weapons and payload carrying capacity to that of Tejas, light combat aircraft (LCA).
...
“The LCA was designed to replace the MiG-21aircraft, whereas the Mk-2 is being designed to replace the Mirage 2000,” Dr Girish Deodhar, programme director of ADA told ET. “It is being redesignated as a medium weight fighter.”

...

Thats great news! Is there going to be a redesign in terms of dimensions? (ala F-2 to the F-16?) -
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Manish_P »

putnanja wrote:Post upgradation Tejas’ Mark-2 to become a medium weight fighter

“The LCA was designed to replace the MiG-21aircraft, whereas the Mk-2 is being designed to replace the Mirage 2000,” Dr Girish Deodhar, programme director of ADA told ET. “It is being redesignated as a medium weight fighter.”
Awesome.. The LCA has developed into a near equivalent of the original Mirage 2000.. the LCA MK-2 might well develop into the near equivalent of the Rafale :twisted:
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Singha »

4 tons mtow increase per the article indicates considerable payload and hopefully length increase without changing the already very large wing.
wing design and testing is very complex and airbus/boeing claim to spend about 1 bil USD+ on any of those new curvy wings design.

wing loading will increase a bit, but its very low now vs contemorary A2G "trucks"
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Cain Marko »

Hopefully they'll incorporate some shaping and stealth features, my fave... Recessed pylons on the fuselage allowing for 4 to 6 AAMs or couple of bombs and wingtip ccms , rcs should be similar to clean profile.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Austin »

If they keep the existing design just add more powerful engine and increase MTOW then its fine but if they change the design , increase length and use more powerful engine then it will be long period of testing too , A 4 ton weight gain for a small fighter is quite a change.

I wish they can make incremental changes possible for Mk2 and get it in squadron service sooner than go for biger changes and delay the program
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Cybaru »

I think 4 ton isn’t that much more than mirage 2Ks max mtow of 17 tons. The Lca navy dimensions posted above are bigger than the m2k by. 0.2 meters.

Given the addition of canards, probable restructuring of wheel placements, addition of 1.3 meter plug, addition of probably 1200-1700 fuel internally, it will probably add 4 tons of weight and be no different than the above naval config other than canards.

So it will be doable and not too far away from what it is now.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by JayS »

Cybaru wrote:I think 4 ton isn’t that much more than mirage 2Ks max mtow of 17 tons. The Lca navy dimensions posted above are bigger than the m2k by. 0.2 meters.

Given the addition of canards, probable restructuring of wheel placements, addition of 1.3 meter plug, addition of probably 1200-1700 fuel internally, it will probably add 4 tons of weight and be no different than the above naval config other than canards.

So it will be doable and not too far away from what it is now.
1.3m plug..? Fore IAF's MK2..? How come..? Last I checked MK2 is suppose to have 0.5m plug. It was my wish that they make it 15m long after they decided to go with canards.

17.5T is more than I expected. NLCA MK2 was suppose to have 16.5T. Anyhow, majority of the hike will be from increased payload capacity. I expected empty weight to be ~7.3T and internal fuel increased to 3.2-3.4T and max payload to 5T. Looks like they will go to max payload of 6T or so.
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Indranil »

I cannot foresee this number. With apptoximately a 10% increase in thrust, i can’t see how they are going to get a more than 10% increase in the clean TOW. At max 15% to account for extra internal fuel. That would put the clean TOW below 11.5 tons. That would leave 6 tons of payload. I don’t know how they could possible carry 6 tons on 7 pylons!
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Kartik »

17.5 tons MTOW for the Tejas Mk2 matches that of the Mirage-2000 exactly, as per Dassault's fact sheet.

With such a high MTOW, I would be surprised if they managed to keep the empty weight below 8000 kgs. Saab could not succeed in keeping the Gripen E's empty weight < 8000 kgs, and its MTOW is 16.5 tons.

And Mirage-2000-5's empty weight is 7900 kgs, not the 7500 kgs that is oft quoted. That is the empty weight of the Mirage-2000C variant, which had fewer hardpoints.

Mirage-2000 single seater length is 14.36m and twin seater is 14.55m. Expect at least a 1 meter fuselage plug, if not more. It would make a lot of sense to me now for ADA to take the Naval LCA Mk2 design and make changes to it as the Tejas Mk2. The Naval LCA Mk2 design incorporated additional internal fuel by widening the fuselage and pushing the wings out. The change in the location of the wing root and MLG attachment points would've also allowed for multiple hardpoints on the center fuselage.

Anyway, hopefully we should see or get more details of the proposed Tejas Mk2 design in a few months time. It doesn't mention canards, but perhaps IR or JayS could confirm if they're on the configuration that's almost frozen.
srin
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by srin »

One question I have is: with a 17.5t MTOW, will a GE F414 suffice ? My concern is - would we be back to "it is underpowered" situation ?
Cybaru
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Cybaru »

JayS wrote:
Cybaru wrote:I think 4 ton isn’t that much more than mirage 2Ks max mtow of 17 tons. The Lca navy dimensions posted above are bigger than the m2k by. 0.2 meters.

Given the addition of canards, probable restructuring of wheel placements, addition of 1.3 meter plug, addition of probably 1200-1700 fuel internally, it will probably add 4 tons of weight and be no different than the above naval config other than canards.

So it will be doable and not too far away from what it is now.
1.3m plug..? Fore IAF's MK2..? How come..? Last I checked MK2 is suppose to have 0.5m plug. It was my wish that they make it 15m long after they decided to go with canards.

17.5T is more than I expected. NLCA MK2 was suppose to have 16.5T. Anyhow, majority of the hike will be from increased payload capacity. I expected empty weight to be ~7.3T and internal fuel increased to 3.2-3.4T and max payload to 5T. Looks like they will go to max payload of 6T or so.
I don't think Ada ever worked on the 0.5 meter plug IAF variant as much. I think a lot of effort went into the mk2 to make it naval compliant and that is where they will pick up from. The 0.5 meter new variant for IAF didn't make sense one way or another. I think ada's initial thought of designing for navy and then extracting for iaf always made more sense and that is what may happen for mk-2 if we are lucky.

The LCA will be no different than mirage2k. The plane wings and plane will be hardened for max payload, but for most work, they will task it as usual, 1 ldp, 1 jammer, 2 pylons A2G (dumb or smart), 2 pylons with tanks (probably larger tanks allowing it more range) and 2CCM (3-4 ton) payload.
Last edited by Cybaru on 18 May 2018 23:50, edited 1 time in total.
Cybaru
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Re: Tejas Mk.2 News & Discussions: 25 February 2018

Post by Cybaru »

srin wrote:One question I have is: with a 17.5t MTOW, will a GE F414 suffice ? My concern is - would we be back to "it is underpowered" situation ?
the m53 powers the m2k-9 and it has never been called under powered. the F414 is very similar plus there is probably an enhanced version on the way.
M53:
Maximum thrust:
64 kN (14,300 lbf) military thrust
95 kN (21,384 lbf) with afterburner
Overall pressure ratio: 9.8:1
Bypass ratio: 0.36:1
Specific fuel consumption:
0.90(kg/daN.h) Dry engine thrust
2.10(kg/daN.h) military thrust
Thrust-to-weight ratio: 6.5
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