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

Kartik · Post by **Kartik** » 13 Feb 2019 02:08

Ok, so hopefully someone who's going to AI-'19 can get that point clarified.

gaurav.p · Post by **gaurav.p** » 13 Feb 2019 02:15

Also it seems that the air brakes are gone due to canards.

Some more empty space.

Kartik · Post by **Kartik** » 13 Feb 2019 02:39

You're right..may not be empty space that could be utilised but surely some weight will come down as the actuators won't be required. But that will be more than compensated by the addition of the canards, their actuators and their weight.

Indranil · Post by **Indranil** » 13 Feb 2019 04:15

No. The air brakes are not shown. They cannot be replaced by canards. The canards can only be used as airbrakes on ground. Not in the air.

JayS · Post by **JayS** » 13 Feb 2019 05:45

Kartik wrote:So the Avionics cover is basically composite skin?

Another question that arose, is there going to be a Tejas Mk2 twin seater? Or will the Tejas Mk1 trainers support conversion onto the Mk2 fleet as well along with simulators?

https://goo.gl/images/MSBjup

In the image there, you can see the composite avionics cover behind the canopy. There is no reason to go for trasperency which is rather costly. IR is correct in saying this will be way cheaper. NLCA was a jugaad case.

Re Trainer version, I wonder if the 20 trainers on order would be sufficient for type conversion. But of coarse IAF may feel they need separate Mk2 trainer too. I'll try to remember to ask this question.

Kartik · Post by **Kartik** » 13 Feb 2019 05:53

If that was the case (cost) then why would it be there on the LCA Navy Mk2 design?

The canopy transparency goes all the way over the avionics bay and affords much better view for the pilot at the back versus the LCA AF Mk2.

Kartik · Post by **Kartik** » 13 Feb 2019 06:01

JayS wrote:
Re Trainer version, I wonder if the 20 trainers on order would be sufficient for type conversion. But of coarse IAF may feel they need separate Mk2 trainer too. I'll try to remember to ask this question.

Yes, please do ask that. Although I do believe that if the two seater is not going to be used as a combat fighter and only for type conversion, then it could be considered a waste of resources building a new Mk2 trainer. Unless the commonality between the types (Mk1/Mk1A and Mk2) is so low and performance so different, that pilots feel the need for a type conversion trainer. Some officers may even argue that twin seaters help some pilots maintain currency on the type, so the IAF could build a case for a Mk2 twin seater as well. But given the lack of adequate human resources and with AMCA and LCA Navy Mk2 also running concurrently, it will stretch ADA.

Similar situation for the Navy as well, where they would probably just go with the LCA Navy Mk1 twin seaters for type conversion and maintaining currency. For them, with much smaller LCA Navy Mk2 numbers overall, there is simply no case for a dedicated LCA Navy Mk2 twin seater.

Rakesh · Post by **Rakesh** » 13 Feb 2019 06:20

@ Kartik: The Rafale C and Rafale M uses the canopy to cover the avionics bay, but under the canopy there is another cover (black in colour). Do you know what that is? It looks like the Naval Tejas Mk2 uses a similar design, but minus the cover. The air force variant of the Tejas Mk2 adopts the Rafale B design. For some weird reason, despite it clearly stating otherwise, I thought the Tejas Mk2 picture you posted above, would share the same design for the Air Force and the Navy.

Rafale C

Rafale M

Rafale B

JayS · Post by **JayS** » 13 Feb 2019 06:32

Kartik, regarding spillway, its part of fuselage assy. See in the image below, no wings, but spillway is there. It should be right above the inlet and splitter plate. But if you see the CAD images from RFI, there is no spillway in FF and in CF there is no gap shown between fuselage and inlet duct. So unless a piece is missing between FF and CF I see no spillway. But since IR says there is, I'll wait for explanation. I am hoping to see a nice model in AI2019 of this canard version. That should clear all doubts.

Re, trainers, trainers will be fully combat ready and will be used for missions even though usually they will be used for training sorties. But you can imagine trainers have shorter legs than single seater versions typically as additional seat add weight and eats into internal fuel capacity, so their utility will be slightly lower. BTW just to clarify, by type conversion here, I meant only training specific to LCA.

Regarding canopy, another thing I felt is that the canopy for MK2 is shorter axially than what we have for MK1.

JayS · Post by **JayS** » 13 Feb 2019 06:54

gaurav.p wrote:
1. Indeed saar, the wing has been pushed back.
4. Yes, the nose seems to be elongated to me as well. Shown in green. Also interesting to note is that the shape of canopy has changed. The joint connected with the avionics cover isn't straight as in mk1. maybe more space for LRUs
5. Also in the rear fuselage, the trail edges end till the end of the fuselage. But in mk1 it isn't the case.
7. There is also something called longerons in the center fuselage. I guess, it is added in order to tackle the vortex of canards.
8. Can someone explain this image? Also the yellow thing in the image, below the stub wing?

Those are interfaces where wing attaches. No fattening. The yellow surface, well its just a surface between intake upper portion and wing lower surface until the two fuse. Since the CAD is in semi-transperent mode its bit confusing, it shows more lines which would be hidden otherwise.

Kartik · Post by **Kartik** » 13 Feb 2019 07:58

JayS wrote:Kartik, regarding spillway, its part of fuselage assy. See in the image below, no wings, but spillway is there. It should be right above the inlet and splitter plate. But if you see the CAD images from RFI, there is no spillway in FF and in CF there is no gap shown between fuselage and inlet duct. So unless a piece is missing between FF and CF I see no spillway. But since IR says there is, I'll wait for explanation. I am hoping to see a nice model in AI2019 of this canard version. That should clear all doubts.

Agreed. As IR mentioned that it is there in the Mk2 design, I'll believe him. But the CAD model should have probably shown that. My guess was that the spillway was no longer required as the canards vortices did the job of strengthening the boundary layer over the wing and wing tip but who knows what the designers found during wind tunnel analysis? And yes, a good quality model would clear a lot of our doubts, although given previous Aero India LCA models, one cannot say for sure.

Re, trainers, trainers will be fully combat ready and will be used for missions even though usually they will be used for training sorties. But you can imagine trainers have shorter legs than single seater versions typically as additional seat add weight and eats into internal fuel capacity, so their utility will be slightly lower. BTW just to clarify, by type conversion here, I meant only training specific to LCA.

But will they need a specific Tejas Mk2 combat capable trainer or just use the Mk1 trainer to convert pilots with extensive ground simulators?

Even for the Tejas Mk1A, there is no plan for a specific Mk1A trainer. They plan on using the Mk1 FOC trainer as the type conversion trainer and that makes sense, since the Mk1A is basically the same flight envelope wise, as the Mk1.

Regarding canopy, another thing I felt is that the canopy for MK2 is shorter axially than what we have for MK1.

So did I. Which is what led me to ask whether the Avionics cover was a continuation of the canopy, like on the LCA Navy Mk2 CAD images, or not. Again, Aero India 2019 should hopefully clear all that doubt.

JayS · Post by **JayS** » 13 Feb 2019 08:28

Kartik wrote:
JayS wrote:Kartik, regarding spillway, its part of fuselage assy. See in the image below, no wings, but spillway is there. It should be right above the inlet and splitter plate. But if you see the CAD images from RFI, there is no spillway in FF and in CF there is no gap shown between fuselage and inlet duct. So unless a piece is missing between FF and CF I see no spillway. But since IR says there is, I'll wait for explanation. I am hoping to see a nice model in AI2019 of this canard version. That should clear all doubts.

Agreed. As IR mentioned that it is there in the Mk2 design, I'll believe him. But the CAD model should have probably shown that. My guess was that the spillway was no longer required as the canards vortices did the job of strengthening the boundary layer over the wing and wing tip but who knows what the designers found during wind tunnel analysis? And yes, a good quality model would clear a lot of our doubts, although given previous Aero India LCA models, one cannot say for sure.

Re, trainers, trainers will be fully combat ready and will be used for missions even though usually they will be used for training sorties. But you can imagine trainers have shorter legs than single seater versions typically as additional seat add weight and eats into internal fuel capacity, so their utility will be slightly lower. BTW just to clarify, by type conversion here, I meant only training specific to LCA.
But will they need a specific Tejas Mk2 combat capable trainer or just use the Mk1 trainer to convert pilots with extensive ground simulators?

Even for the Tejas Mk1A, there is no plan for a specific Mk1A trainer. They plan on using the Mk1 FOC trainer as the type conversion trainer and that makes sense, since the Mk1A is basically the same flight envelope wise, as the Mk1.

Regarding canopy, another thing I felt is that the canopy for MK2 is shorter axially than what we have for MK1.
So did I. Which is what led me to ask whether the Avionics cover was a continuation of the canopy, like on the LCA Navy Mk2 CAD images, or not. Again, Aero India 2019 should hopefully clear all that doubt.

I thought the same too wrt canard and spillway. That may be its dropped due to canards. The canard tip vortex will be still slightly outboard to the spillway. Lets wait and watch.

IN terms of handling and pikot interface, Mk2 should also be quite the same. The changes could be taken care through simulator, I feel. So a pilot trained on MK1 Trainer with some simulator training should be able to handle MK2 easily I feel.

Indranil · Post by **Indranil** » 13 Feb 2019 10:07

Spillway is there in the cad drawings of the mid section. You have to see carefully. The transparency of the model makes it difficult to see. It is not so much for energizing the wake, but simply boundary layer deposition.

Jay, please check mail.

Dileep · Post by **Dileep** » 13 Feb 2019 11:22

Width of the fuselage is increased. IIRC MK1 was something like 750mm. MK2 is 1100mm. Can put in nice 'cinemascope istyle' glass cockpit

JayS · Post by **JayS** » 13 Feb 2019 11:58

Dileep wrote:Width of the fuselage is increased. IIRC MK1 was something like 750mm. MK2 is 1100mm. Can put in nice 'cinemascope istyle' glass cockpit

Did you mean width at the cockpit area..? The Radome base dia for MK1 is 883 mm for reference. MK1 has rather thin section at the cockpit till the where intakes start. That must be ~750mm. The link below shows FF structural sub-assy from behind. The rear section looks closer to 1100 mm than 750 mm to my eyes. Si it expands a bit after the intakes.
https://timesofindia.indiatimes.com/ind ... 363473.cms

The shown section in the RFI seems to be from somewhere behind the cockpit, in the avionics bay to me. Its difficult to say dimensions at the cockpit. You may be right. But I am just thinking, the fattening is too much if we consider 750mm to 1100mm, given addition of canards and canopy shape change, area rule wise.

Just back of the envelope calculations say MK2 should have additional apprx 1.5-2 cubic m internal space. So we should see significant increase in internal fuel.

Prasad · Post by **Prasad** » 13 Feb 2019 13:47

The Radome base dia for MK1 is 883 mm

Not 900mm? I remember reading somewhere, cant quite find the link now.

JayS · Post by **JayS** » 13 Feb 2019 14:38

Prasad wrote:
The Radome base dia for MK1 is 883 mm
Not 900mm? I remember reading somewhere, cant quite find the link now.

883.5

Just google for "LCA Radome". First one itself is Radome schematic from that Radome tender.

suryag · Post by **suryag** » 14 Feb 2019 07:37

IR sir you better have that article ready tomorrow or we will send dossiers to you everyday

Indranil · Post by **Indranil** » 14 Feb 2019 12:03

Come on surya ji! What has the good Admiral taught us? Sabr ka fal mitha(i) hota hai.

Bala Vignesh · Post by **Bala Vignesh** » 14 Feb 2019 14:42

Indranil wrote:Come on surya ji! What has the good Admiral taught us? Sabr ka fal mitha(i) hota hai.

But the good admiral has still not given his quota of Mitha(I) yet!!

nachiket · Post by **nachiket** » 16 Feb 2019 00:42

Indranil wrote:Come on surya ji! What has the good Admiral taught us? Sabr ka fal mitha(i) hota hai.

Bad example! Since we never saw even an ounce of the promised mithai. I can only conclude that the Admiral ate all 10000 tonnes of it himself!

SaiK · Post by **SaiK** » 16 Feb 2019 02:54

remember, we need space for retractable refueller as well.

re: canopy extension: I read it as "avionics cover" in the dig of the first pdf.

suryag · Post by **suryag** » 16 Feb 2019 08:39

Waiting waiting waiting for IRsir

vipins · Post by **vipins** » 16 Feb 2019 21:25

http://www.pib.nic.in/PressReleaseIframePage.aspx?PRID=1564890#.XGgt-6sYsi0.twitter
Looks like mk2 is officially designated MWF now.

Indranil · Post by **Indranil** » 17 Feb 2019 04:20

Yes, it is called MWF now.

Surya ji, the skeletons are ready. Fleshing it now. Great to have JayS as my co-writer.

The write up will carry some details of MK1 that are not yet covered outside, and Mk2.

Sorry for the delay.

Haridas · Post by **Haridas** » 17 Feb 2019 05:55

Would be interesting is to know : What is the delta between the IAF'S ASR between MWF & MMRCA?

Cybaru · Post by **Cybaru** » 17 Feb 2019 15:19

clean up on aisle MK2 requested.. Mig29 has no place here.

ashishvikas · Post by **ashishvikas** » 17 Feb 2019 17:29

Indranil wrote:Yes, it is called MWF now.

Please consider to rename this thread as well.

Rakesh · Post by **Rakesh** » 17 Feb 2019 19:39

Cybaru wrote:clean up on aisle MK2 requested.. Mig29 has no place here.

All MiG-29 discussions have been moved to the Indian Air Force: News & Discussion thread. Thank You.

Gyan · Post by **Gyan** » 17 Feb 2019 21:26

Guys take a hundred pics of MWF at Def Expo, so that we have enough material for discussion for next two years.

VickyAvinash · Post by **VickyAvinash** » 17 Feb 2019 21:47

Indranil wrote:Yes, it is called MWF now.

Surya ji, the skeletons are ready. Fleshing it now. Great to have JayS as my co-writer.

The write up will carry some details of MK1 that are not yet covered outside, and Mk2.

Sorry for the delay.

IR sir, no pressure at all. However it will be great if it is possible to share a tentative timeline on the article. I have been visiting this thread every hour hoping to see it for last 3 days. Really looking forward to it.

suryag · Post by **suryag** » 17 Feb 2019 22:04

Vicky sir, a good tailor takes time

IR and JayS sir will release the document at a time of their choosing

after all these guys have big day jobs

JayS · Post by **JayS** » 17 Feb 2019 23:20

I have had enough time from Thursday onwards, but the Pulwama attack has dampened my enthu significantly. I spent couple of days following only that.

ks_sachin · Post by **ks_sachin** » 18 Feb 2019 04:08

It was a most depressing last few days.....

SaiK · Post by **SaiK** » 20 Feb 2019 03:14

India’s Medium Weight Fighter, The Rechristened LCA Tejas Mk.2, To Be Unveiled
https://www.livefistdefence.com/2019/02 ... eiled.html

Rakesh · Post by **Rakesh** » 20 Feb 2019 08:39

It is HERE!!!! YES!!! I count 11 hardpoints!

https://twitter.com/livefist/status/1098049259868430338 ---> FIRST LOOK! India’s ‘Medium Weight Fighter’, the rechristened LCA Tejas Mk.2 sports canards.

Rakesh · Post by **Rakesh** » 20 Feb 2019 08:41

VIDEO

https://twitter.com/livefist/status/1098049714828861440 ---> We’re live first & exclusive with India’s new canard concept — the Medium Weight Fighter (the re-christened LCA Mk.2)

SKrishna · Post by **SKrishna** » 20 Feb 2019 08:52

I see no spill away opening. May be obscured by the canard but not visible to me in the video. Folks going there please confirm. Integrated IRST I suppose and also 11 hard points make it a beast.

tushar_m · Post by **tushar_m** » 20 Feb 2019 08:56

Canards
Conformal fuel tank ???
Infra-red search and track
F414

dkhare · Post by **dkhare** » 20 Feb 2019 09:12

Beautiful bird!
1. Canards
2. IRST?
3. Fixed IFR probe?
4. Wing tip pylons!
5. Twin racks with Derbys!
6. Gun bay relocated with pylon added on starboard inlet chin
7. 11 pylons total!
8. No gun visible on wing root.
9. Very slight wing fuselage blending on the bottom.
10. Unclear if MLG configuration is within fuselage or retracts into wing root.