Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

The Military Issues & History Forum is a venue to discuss issues relating to the military aspects of the Indian Armed Forces, whether the past, present or future. We request members to kindly stay within the mandate of this forum and keep their exchanges of views, on a civilised level, however vehemently any disagreement may be felt. All feedback regarding forum usage may be sent to the moderators using the Feedback Form or by clicking the Report Post Icon in any objectionable post for proper action. Please note that the views expressed by the Members and Moderators on these discussion boards are that of the individuals only and do not reflect the official policy or view of the Bharat-Rakshak.com Website. Copyright Violation is strictly prohibited and may result in revocation of your posting rights - please read the FAQ for full details. Users must also abide by the Forum Guidelines at all times.
Post Reply
AkshaySG
BRFite
Posts: 412
Joined: 30 Jul 2020 08:51

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by AkshaySG »

A bit OT, But are we expecting any name change for Mk2/MWF?

Simply Mk2 would be a little confusing when we also have Mk1, Mk1A, M2k, MKI in our inventory.

As LCA became Tejas maybe MWF could have a different name too.

Could also be useful to implement some naming conventions now that we have multiple Indian Jets and helo varieties planned in the near future


Could even help with exports as some countries might prefer a neutral designation rather than a name in a language they don't understand
nash
BRFite
Posts: 946
Joined: 08 Aug 2008 16:48

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by nash »

https://twitter.com/CNBCTV18News/status ... 5114727431
'Hope to deliver first Tejas LCA Mark-2 by 2025-26', says HAL CMD R Madhavan as the company receives the largest ever defence order from the govt to supply 83 fighter & trainer LCA to the IAF.
Rollout of First Tejas-MkII by Aug 2022, first flight by Aug-2023 and in three year ready for production. This sound ambitious given HAL track record, I wish them best to deliver this time.
LakshmanPST
BRFite
Posts: 673
Joined: 05 Apr 2019 18:23

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by LakshmanPST »

A doubt... I'm not sure this was discussed here before...

Will IAF order all 8-9 squadrons on Tejas Mk2 in one go after it is fully ready with FOC...??? Or will they order around 2 squadrons of IOC initially and remaining 6-7 squadrons later after FOC...???
-
This is important becoz. if Tejas gets IOC in around 2025, and Contract for 2 squadrons of IOC is also signed in 2025, we can expect the first Series Production IOC jet by 2028 and 2 squadrons by 2031 itself...
If they start a new line of Mk2 with 8 jets per year capacity in 2025 for IOC Mk2, parallelly with existing two Mk1A production lines, that will be great... It will also help in streamlining any unexpected problems that might arise during production...
The Mk1A lines can then start FOC Mk2 jets production starting 2029 itself along with this line and a new 4th line...
-
At this point of time, I'm only speculating... But I feel there is a possibility of this happening...
nam
BRF Oldie
Posts: 4712
Joined: 05 Jan 2017 20:48

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by nam »

We can consider MWF equivalent to F16 Block 60 development. First flight 2003 and IOC 2005! The concept is similar. Higher thrust engines, using existing avionics and weapons.

Infact the perfect comparison is with Super hornet. F404 to F414 with existing kit. Same development timeline. 2-3 to IOC from first flight.

MWF: MK1A radar, avonics , weapons with F414 engine. I think it is doable.
Rakesh
Forum Moderator
Posts: 18274
Joined: 15 Jan 2004 12:31
Location: Planet Earth
Contact:

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Rakesh »

https://twitter.com/DefenceDecode/statu ... 08452?s=20 --->
First Tejas Mk2 Prototype to Roll-out in August 2022 and first flight in August 2023: HAL Chief.

Image
Ankit Desai
BRFite
Posts: 634
Joined: 05 May 2006 21:28
Location: Gujarat

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Ankit Desai »

AMCA + TEJAS MK2 | TEDBF design revealed

Hindi
====


AMCA 2021 (MK1 & MK2) - 5.5 Generation Fighter Jet

Hindi
=====


Stealthy TEDBF Sneak Peek into the design

-Ankit
ramana
Forum Moderator
Posts: 59773
Joined: 01 Jan 1970 05:30

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by ramana »

LakshmanPST wrote:A doubt... I'm not sure this was discussed here before...

Will IAF order all 8-9 squadrons on Tejas Mk2 in one go after it is fully ready with FOC...??? Or will they order around 2 squadrons of IOC initially and remaining 6-7 squadrons later after FOC...???
-
This is important becoz. if Tejas gets IOC in around 2025, and Contract for 2 squadrons of IOC is also signed in 2025, we can expect the first Series Production IOC jet by 2028 and 2 squadrons by 2031 itself...
If they start a new line of Mk2 with 8 jets per year capacity in 2025 for IOC Mk2, parallelly with existing two Mk1A production lines, that will be great... It will also help in streamlining any unexpected problems that might arise during production...
The Mk1A lines can then start FOC Mk2 jets production starting 2029 itself along with this line and a new 4th line...
-
At this point of time, I'm only speculating... But I feel there is a possibility of this happening...
I hope it's all the planes at one go and cut in FOC configuration around 3rd squadron or what ever makes sense.
Kanson
BRF Oldie
Posts: 3065
Joined: 20 Oct 2006 21:00

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Kanson »

LakshmanPST wrote:A doubt... I'm not sure this was discussed here before...

Will IAF order all 8-9 squadrons on Tejas Mk2 in one go after it is fully ready with FOC...??? Or will they order around 2 squadrons of IOC initially and remaining 6-7 squadrons later after FOC...???
-
This is important becoz. if Tejas gets IOC in around 2025, and Contract for 2 squadrons of IOC is also signed in 2025, we can expect the first Series Production IOC jet by 2028 and 2 squadrons by 2031 itself...
If they start a new line of Mk2 with 8 jets per year capacity in 2025 for IOC Mk2, parallelly with existing two Mk1A production lines, that will be great... It will also help in streamlining any unexpected problems that might arise during production...
The Mk1A lines can then start FOC Mk2 jets production starting 2029 itself along with this line and a new 4th line...
-
At this point of time, I'm only speculating... But I feel there is a possibility of this happening...
Simple... as i see it, there won't be separate IOC & FOC later. Jets will be delivered in single Final production variant. This is to reduce dev time and to maintain strict timeline.

At present Mk2 is strategically of higher importance. More than even AMCA. ADA has to deliver as per previously noted timeline. Strategically so important that ADA can't deviate.

ADA is compressing the activities. Unlike flight testing for every phase one by one, trial & dev will be done hollistically of achieving the required final configuration. So i believe, from day 1, jets will be deployable at border & mission capable. Regarding future variants, it could in blocks like Mk2_blk10.

The way ADA is compressing the timeline, no more we are going to compare the timelines of other aero giant products to gauge our products, once mk2 is done. I believe this is the case with AMCA too.

---------------------

It is very good that ADA dropped DSI for mk2 in view of maintaining the timeline.
Kartik
BRF Oldie
Posts: 5722
Joined: 04 Feb 2004 12:31

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Kartik »

Kanson wrote:
LakshmanPST wrote:A doubt... I'm not sure this was discussed here before...

Will IAF order all 8-9 squadrons on Tejas Mk2 in one go after it is fully ready with FOC...??? Or will they order around 2 squadrons of IOC initially and remaining 6-7 squadrons later after FOC...???
-
This is important becoz. if Tejas gets IOC in around 2025, and Contract for 2 squadrons of IOC is also signed in 2025, we can expect the first Series Production IOC jet by 2028 and 2 squadrons by 2031 itself...
If they start a new line of Mk2 with 8 jets per year capacity in 2025 for IOC Mk2, parallelly with existing two Mk1A production lines, that will be great... It will also help in streamlining any unexpected problems that might arise during production...
The Mk1A lines can then start FOC Mk2 jets production starting 2029 itself along with this line and a new 4th line...
-
At this point of time, I'm only speculating... But I feel there is a possibility of this happening...
Simple... as i see it, there won't be separate IOC & FOC later. Jets will be delivered in single Final production variant. This is to reduce dev time and to maintain strict timeline.

At present Mk2 is strategically of higher importance. More than even AMCA. ADA has to deliver as per previously noted timeline. Strategically so important that ADA can't deviate.

ADA is compressing the activities. Unlike flight testing for every phase one by one, trial & dev will be done hollistically of achieving the required final configuration. So i believe, from day 1, jets will be deployable at border & mission capable. Regarding future variants, it could in blocks like Mk2_blk10.

The way ADA is compressing the timeline, no more we are going to compare the timelines of other aero giant products to gauge our products, once mk2 is done. I believe this is the case with AMCA too.

---------------------

It is very good that ADA dropped DSI for mk2 in view of maintaining the timeline.
Tejas Mk2 will also have IOC and FOC. I don't understand why people keep confusing "Production Standard" Prototypes to mean that there are no separate IOC and FOC phases.

All of the Tejas Mk2's software, avionics and systems, weapons qualification, etc. will not be fully qualified from the get go. It's not like they're just taking all the systems from Tejas Mk1 and using it as is. Where there are new systems or upgraded LRUs, they will need to qualified again. The fighter's weights are different, it's FCS has a new surface (canards), it's Brake Management System needs to be qualified again, it's Fuel Management System needs to be qualified again, Landing gear is new, it's cockpit controls are different, it's displays are different, there's a new IRST, etc.

Certification is a process with stages, as more flight tests are conducted, more of these systems and weapons will be cleared. The full flight envelope may be opened up earlier this time, with fewer flight tests, given how much experience has been gained from the Tejas program, but there will still be hundreds of hours of flight testing to be conducted to get to Full Operational Capability.
Shekhar Singh
BRFite -Trainee
Posts: 40
Joined: 16 Sep 2018 14:55

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Shekhar Singh »

To all seniors
Don't you think that GE 414 thrust will be inadequate for 17500 mto aircraft?
Kartik
BRF Oldie
Posts: 5722
Joined: 04 Feb 2004 12:31

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Kartik »

Shekhar Singh wrote:To all seniors
Don't you think that GE 414 thrust will be inadequate for 17500 mto aircraft?
Just compare the 98 kN afterburning thrust of the GE F-414-INS6 with the 95 kN thrust that the Snecma M-88-P2 produces for the Mirage-2000 for almost similar weights. Has anyone ever complained about lack of thrust on a Mirage-2000? I don't believe so.

17,500 kgs is the Max TOW of the Tejas Mk2, a configuration in which it will be limited by the FCS to 5G or so for maneuvers. As fuel burns up or payload is dispensed, the weight figure will start reducing and the Tejas Mk2's FCS will gradually begin to allow more g loads till it can reach 9Gs. In normal missions, where it's going to be carrying drop tanks and maybe 2-4 BVRAAMs + CCMs, the 98 kN afterburning thrust will be sufficient.
Last edited by Kartik on 22 Jan 2021 17:49, edited 1 time in total.
hemant_sai
BRFite
Posts: 181
Joined: 13 Dec 2018 12:13

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by hemant_sai »

MWF is going to have 5 pre-production test models. TEDBF design-analysis for DSI intakes will finish by 2023 by all means.
And TEDBF first rollout is expected in 2025-26. Then won't it be prudent to at-least use 1 out 5 test-models of MWF to try DSI intakes for MWF?

Will redesign of intakes from 2023-25 disrupt MWF timelines? If yes, then DSI intakes can be scheduled for later batches of MWF may be after first 2-3 sqdns?

Dr Girish D. mentioned that DSI is definitely a plus and all future models are going to have it. In that case why MWF should not get it?
hemant_sai
BRFite
Posts: 181
Joined: 13 Dec 2018 12:13

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by hemant_sai »

Kartik wrote:
Shekhar Singh wrote:To all seniors
Don't you think that GE 414 thrust will be inadequate for 17500 mto aircraft?
Just compare the 98 kN afterburning thrust of the GE F-414-INS6 with the [url=https://www.safran-aircraft-engines.com ... 2011.pdf95 kN thrust that the Snecma M-88-P2[/url] produces for the Mirage-2000 for almost similar weights. Has anyone ever complained about lack of thrust on a Mirage-2000? I don't believe so.

17,500 kgs is the Max TOW of the Tejas Mk2, a configuration in which it will be limited by the FCS to 5G or so for maneuvers. As fuel burns up or payload is dispensed, the weight figure will start reducing and the Tejas Mk2's FCS will gradually begin to allow more g loads till it can reach 9Gs. In normal missions, where it's going to be carrying drop tanks and maybe 2-4 BVRAAMs + CCMs, the 98 kN afterburning thrust will be sufficient.
Dry thrust of GE414 is much lesser compared to Mirage engine. Will it have any implications about restrictions on altitude with use of dry thrust and possible payload?
Kartik
BRF Oldie
Posts: 5722
Joined: 04 Feb 2004 12:31

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Kartik »

hemant_sai wrote:
Kartik wrote:
Just compare the 98 kN afterburning thrust of the GE F-414-INS6 with the [url=https://www.safran-aircraft-engines.com ... 2011.pdf95 kN thrust that the Snecma M-88-P2[/url] produces for the Mirage-2000 for almost similar weights. Has anyone ever complained about lack of thrust on a Mirage-2000? I don't believe so.

17,500 kgs is the Max TOW of the Tejas Mk2, a configuration in which it will be limited by the FCS to 5G or so for maneuvers. As fuel burns up or payload is dispensed, the weight figure will start reducing and the Tejas Mk2's FCS will gradually begin to allow more g loads till it can reach 9Gs. In normal missions, where it's going to be carrying drop tanks and maybe 2-4 BVRAAMs + CCMs, the 98 kN afterburning thrust will be sufficient.
Dry thrust of GE414 is much lesser compared to Mirage engine. Will it have any implications about restrictions on altitude with use of dry thrust and possible payload?
Hardly so. GE F-414 is quoted at ~63 kN dry thrust and M-53-P2 is at 65 kN.
Kanson
BRF Oldie
Posts: 3065
Joined: 20 Oct 2006 21:00

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Kanson »

Kartik wrote:
Kanson wrote:
Simple... as i see it, there won't be separate IOC & FOC later. Jets will be delivered in single Final production variant. This is to reduce dev time and to maintain strict timeline.

At present Mk2 is strategically of higher importance. More than even AMCA. ADA has to deliver as per previously noted timeline. Strategically so important that ADA can't deviate.

ADA is compressing the activities. Unlike flight testing for every phase one by one, trial & dev will be done hollistically of achieving the required final configuration. So i believe, from day 1, jets will be deployable at border & mission capable. Regarding future variants, it could in blocks like Mk2_blk10.

The way ADA is compressing the timeline, no more we are going to compare the timelines of other aero giant products to gauge our products, once mk2 is done. I believe this is the case with AMCA too.

---------------------

It is very good that ADA dropped DSI for mk2 in view of maintaining the timeline.
Tejas Mk2 will also have IOC and FOC. I don't understand why people keep confusing "Production Standard" Prototypes to mean that there are no separate IOC and FOC phases.

All of the Tejas Mk2's software, avionics and systems, weapons qualification, etc. will not be fully qualified from the get go. It's not like they're just taking all the systems from Tejas Mk1 and using it as is. Where there are new systems or upgraded LRUs, they will need to qualified again. The fighter's weights are different, it's FCS has a new surface (canards), it's Brake Management System needs to be qualified again, it's Fuel Management System needs to be qualified again, Landing gear is new, it's cockpit controls are different, it's displays are different, there's a new IRST, etc.

Certification is a process with stages, as more flight tests are conducted, more of these systems and weapons will be cleared. The full flight envelope may be opened up earlier this time, with fewer flight tests, given how much experience has been gained from the Tejas program, but there will still be hundreds of hours of flight testing to be conducted to get to Full Operational Capability.
Thanks for the reply. i'm not talking about skipping the testing. From what i heard & understood, it is about compressing the multiple tasks that needs to be accomplished within the time.
Say, in single flight whatever data that can be collected for vatious tasks will happen. Activities for various milestones will be clubbed. For ex. data collection for weapon testing could perhaps begin in the first week. What i'm saying is all the data needed for weapon cert phase will not be done separately in single block. It might happen perhaps part by part, clubbed along with other activities, thereby compressing the timeline.

I understand mk2 is far different from mk1.
Vivek K
BRF Oldie
Posts: 2931
Joined: 15 Mar 2002 12:31

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Vivek K »

Can HAL/DRDO make more prototypes quicker and have a pre-determined testing plan that the larger number of PVs could knock off quicker? Can the LCAs FCL be quickly adapted for the MK2 and will MK2 also be composite?
Kanson
BRF Oldie
Posts: 3065
Joined: 20 Oct 2006 21:00

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Kanson »

hemant_sai wrote:MWF is going to have 5 pre-production test models. TEDBF design-analysis for DSI intakes will finish by 2023 by all means.
And TEDBF first rollout is expected in 2025-26. Then won't it be prudent to at-least use 1 out 5 test-models of MWF to try DSI intakes for MWF?

Will redesign of intakes from 2023-25 disrupt MWF timelines? If yes, then DSI intakes can be scheduled for later batches of MWF may be after first 2-3 sqdns?

Dr Girish D. mentioned that DSI is definitely a plus and all future models are going to have it. In that case why MWF should not get it?
We hope Tejas team could accomplish the task in exemplary manner. Once DSI tech s ready, def we will see them in mk2.

Earlier heard, ADA was trying DSI for MWF. As the tech was taking more time, we feared ADA was losing the game by chasing the tech.
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Indranil »

It is not like DSI tech is not ready. The DSI of one aircraft doesn't work on another. To develop the DSI for Mk2, they have to do CFD, then WTT, then in flight testing, and finally quals. That's a resource allocation question. Should Mk2 be made to wait for it? When Gripen E, and Rafales can continue production with splitter plates?
hemant_sai
BRFite
Posts: 181
Joined: 13 Dec 2018 12:13

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by hemant_sai »

Kartik wrote:
hemant_sai wrote:
Dry thrust of GE414 is much lesser compared to Mirage engine. Will it have any implications about restrictions on altitude with use of dry thrust and possible payload?
Hardly so. GE F-414 is quoted at ~63 kN dry thrust and M-53-P2 is at 65 kN.
Wiki and this twitter says 58KN of dry thrust -
https://twitter.com/aerodynamic111/stat ... 53?lang=en

though wiki doesn't specifically mentions about F414-GE-INS6 - I doubt it will be that much improvement for India version - 63 from 58.
brar_w
BRF Oldie
Posts: 10694
Joined: 11 Aug 2016 06:14

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by brar_w »

The F414-400 has an uninstalled "dry" thrust between 62 and 64 kN depending upon variant and operational parameters at the time of measurement. So how much can one confidently say dry thrust would be installed and for the relevant Tajas variant? I would imagine that it should be around 60kN at the very least. Could be more.
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Indranil »

I would say around 60 kN too, but with a better TWR.
Shekhar Singh
BRFite -Trainee
Posts: 40
Joined: 16 Sep 2018 14:55

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Shekhar Singh »

hemant_sai wrote:
Kartik wrote:
Hardly so. GE F-414 is quoted at ~63 kN dry thrust and M-53-P2 is at 65 kN.
Wiki and this twitter says 58KN of dry thrust -
https://twitter.com/aerodynamic111/stat ... 53?lang=en

though wiki doesn't specifically mentions about F414-GE-INS6 - I doubt it will be that much improvement for India version - 63 from 58.
As per GE.com The F414-GE-INS6 is the highest-thrust F414 model.
Aditya_V
BRF Oldie
Posts: 14332
Joined: 05 Apr 2006 16:25

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Aditya_V »

The Dry thrust of the GE 404 IN 20 is around 55Kn, it is safe to assume that it will be 10-15% higher in the GE 414 where wet thrust goes from 84kn to 98kn.

How I do know, HAL Tejas website gives GE In20 dry thrust as 5618 kgf of and GE Aviation website gives the wet thrust numbers. So 5618*9.807/1000= 55Kn. Ball park dry thrust of GE 414 should be around 55×84/98= 64kn with around 5% variation
brar_w
BRF Oldie
Posts: 10694
Joined: 11 Aug 2016 06:14

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by brar_w »

Uninstalled dry thrust for the F-414 is known within a set of stipulated parameters. In the end the guesswork really is into the installed thrust specific to the variant used on the MWF and AMCA. 60kN is a good number to use as reference. Any deviation in either direction will not be operationally meaningful so it is a good number to use.
nam
BRF Oldie
Posts: 4712
Joined: 05 Jan 2017 20:48

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by nam »

Given that MWF prototype needs to rollout by mid-2022, LRDE would be working on the bigger version for MWF to prepare it by atleast mid-22, to integrate it with the 2nd prototype.

Hope they create one for Su30 at the same time and HAL does a certification, without having to wait for IAF & MOD making their mind up.
fanne
BRF Oldie
Posts: 4282
Joined: 11 Feb 1999 12:31

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by fanne »

Aditya_V wrote:The Dry thrust of the GE 404 IN 20 is around 55Kn, it is safe to assume that it will be 10-15% higher in the GE 414 where wet thrust goes from 84kn to 98kn.

How I do know, HAL Tejas website gives GE In20 dry thrust as 5618 kgf of and GE Aviation website gives the wet thrust numbers. So 5618*9.807/1000= 55Kn. Ball park dry thrust of GE 414 should be around 55×84/98= 64kn with around 5% variation
Typically dry thrust is 2/3 of wet thrust. That is true for most more engie
nachiket
Forum Moderator
Posts: 9102
Joined: 02 Dec 2008 10:49

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by nachiket »

hemant_sai wrote:MWF is going to have 5 pre-production test models. TEDBF design-analysis for DSI intakes will finish by 2023 by all means.
And TEDBF first rollout is expected in 2025-26. Then won't it be prudent to at-least use 1 out 5 test-models of MWF to try DSI intakes for MWF?

Will redesign of intakes from 2023-25 disrupt MWF timelines? If yes, then DSI intakes can be scheduled for later batches of MWF may be after first 2-3 sqdns?

Dr Girish D. mentioned that DSI is definitely a plus and all future models are going to have it. In that case why MWF should not get it?
He mentions the primary advantage of the DSI being a reduced frontal RCS. Very important for the AMCA but it is not a major design consideration for the MWF. Not sure why we would complicate things by redesigning the intakes halfway through the procurement process. Most modern 4th gen fighters including the Rafale, Typhoon and Gripen do not have DSI's. Neither does the F-22 for that matter.
bharathp
BRFite
Posts: 453
Joined: 24 Jul 2017 03:44

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by bharathp »

https://www.youtube.com/watch?v=ZpMyAo68agQ

check 7:24 onwards
the young scientist working on MK 2
coming out in aug 2022

design completed, studied, proved, stamped by experts around india.
venkat_r
BRFite
Posts: 374
Joined: 20 Feb 2001 12:31

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by venkat_r »

Yes, it is great to see that passion and the pride this scientist has in Mark 2 8)
astal
BRFite
Posts: 185
Joined: 07 Jul 2005 03:06
Location: virtual back bench

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by astal »

Indranil and JayS and other aerodynamics gurus, I have a couple of questions with respect to addition of Canards in front of the air intakes and how that will impact intake air flow.

Ever since Tejas MK2 pictures emerged and you came out with your seminal articles about 2 years ago it seems like the canards, its interaction with the FBW system and its impact on engine air flow are the only big uncertainties WRT Tejas MK2. The rest of the refinements and improvements are less risky (to an uninformed observer like me)

Are they looking at changing the intakes (lengthening or shape changes)?
How much as the re-write of the control laws is needed with the addition of extra actuators for the canards? Is it fairly doable/low risk? Or will almost all test points have to be revisited?
Last edited by astal on 27 Jan 2021 00:58, edited 1 time in total.
nachiket
Forum Moderator
Posts: 9102
Joined: 02 Dec 2008 10:49

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by nachiket »

One surprising tidbit from Dr. Madhusudana Rao's interview is that he mentioned Nirbhay as one of the weapons they are looking at integrating on the Mk2. He also mentioned the max range of the standoff weapons that can be launched from the Mk2 as 570km. Is there a slightly smaller ~600km air-launched Nirbhay variant in development somewhere?

He also mentions the Brahmos-NG as a future weapon to be integrated which is less of a surprise. Aside from the overall payload, range and transonic acceleration improvement over the Mk1, he also mentions that the HP's are strengthened to carry upto 1800kg of load, so that heavy weapons can be integrated with the aircraft.
nachiket
Forum Moderator
Posts: 9102
Joined: 02 Dec 2008 10:49

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by nachiket »

astal wrote: Are they looking at changing the intakes (lengthening or shape changes)?
This part was covered in Indranil and Nilesh's article in DDR: Link
On the other hand, the air intakes have been moved slightly aft, proportional only to the significantly smaller nose plug. This has resulted in a configuration where the intakes are no longer shielded by the wing, as is the case with the Mk1. However, the introduction of the canards should provide this shielding effect which helps straighten and redirect airflow to the intakes during high angle of attack manoeuvres, to some extent.

...

The splitter plates as well as the air intakes are canted backwards. The intakes also have a subtle sweep added to them. This is expected to result in optimal shock structure in the local vicinity which would reduce spillage drag at supersonic speeds and result in better intake performance. An improved intake cowl contours and the new 3-door auxiliary intake design will also be incorporated. All these modifications improve intake aerodynamics by improving pressure recovery and better uniformity of the flow at low speed, high Angle of Attack (AoA) regimes. This will lead to augmented thrust and reduced chances of engine stall. The low energy boundary layer flow separated by the splitter plate will be completely redirected under the fuselage now. The slot which redirects some of this air over the wing in MK1 is eliminated in MWF, as smooth flow over the wings behind the canards is desirable.
The effect of the canards on overall aerodynamics of the aircraft and their design details are also covered in it. I wouldn't be worried about the FBW. NAL's CLAW team did such a fantastic job with the Mk1 FBW. They are brimming with confidence now after gaining all that experience. They should be able to handle whatever complexities the canards and other changes throw at them.
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Indranil »

astal wrote:Indranil and JayS and other aerodynamic gurus, I have a couple of questions with respect to addition of Canards in front of the air intakes and how that will impact intake air flow.

Ever since Tejas MK2 pictures emerged and you came out with tour seminal articles about 2 years ago it seems like the canards, its interaction with the FBW system and its impact on engine air flow are the only big uncertainties WRT Tejas MK2. The rest of the refinements and improvements are less risky (to an uninformed observer like me)

Are they looking at changing the intakes (lengthening or shape changes)?
How much as the re-write of the control laws is needed with the addition of extra actuators for the canards? Is it fairly doable/low risk? Or will almost all test points have to be revisited?
No canards will not affect the airflow into the engine. However there are quite a few changes:

Of course, the inlet is widened to accommodate for higher airflow.

The inlet is no longer shielded by the leading edge of the wing. This shielding used to provide better pressure recovery at supersonic speeds. The inlets on Mk2 will now extend beyond the LE and the splitter plates will be modified to create the necessary shock waves at supersonic speeds. The papers that I last studied said that the pressure recovery is still not to the level of the Mk1. The lengthened inlet is also heavier meaning higher induced drag*. But the better area ruling on Mk2 and the reduced wave drag can overcome these two and provide a net gain. Notice that the new inlet is also canted to make the area curve even smoother.

There was one aspect which was talked about but is difficult to discern by looking at the model. There were studying the aerofoil of the lip for better pressure recovery over a wider band of the flight envelop. To do this, the aerofoil at the top and bottom parts of the lips would be different. As I said earlier, I don’t know if this has been adopted.

*So, whoever tells you that ADA designers did not know about area-rule, first do a big facepalm. Then tell why they traded off area ruling for lower weight/induced drag and pressure recovery
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by Indranil »

nachiket wrote:One surprising tidbit from Dr. Madhusudana Rao's interview is that he mentioned Nirbhay as one of the weapons they are looking at integrating on the Mk2. He also mentioned the max range of the standoff weapons that can be launched from the Mk2 as 570km. Is there a slightly smaller ~600km air-launched Nirbhay variant in development somewhere?
The 570 km range is that of Scalp. But I believe there is a lighter Nirbhay in the making. The final version of the ground launched Nirbhay weighs 1250 kgs + booster. I believe that the air launched version with a slightly shorter airframe(by around 1.5 mtrs) and dia (by about 15 mm) is in the making. If true such a missile will weigh around 1000 kgs and should be able to reach ~800 kms.
astal
BRFite
Posts: 185
Joined: 07 Jul 2005 03:06
Location: virtual back bench

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by astal »

Indranil wrote: No canards will not affect the airflow into the engine. However there are quite a few changes:
..
Thanks, Indranil. I appreciate your answers.
nachiket
Forum Moderator
Posts: 9102
Joined: 02 Dec 2008 10:49

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by nachiket »

Indranil wrote: The 570 km range is that of Scalp. But I believe there is a lighter Nirbhay in the making. The final version of the ground launched Nirbhay weighs 1250 kgs + booster. I believe that the air launched version would weigh around 1000 kgs. But it's range should by close to 1000 km.
Thanks. That makes sense. Eagerly waiting for the Nirbhay ALCM. We need a counterpart to the Chinese H-6 bombers and their air-launched CJ-10's.
nam
BRF Oldie
Posts: 4712
Joined: 05 Jan 2017 20:48

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by nam »

I hope when they say Scalp, they mean an Indian weapon similar to Scalp. I really don't us to spend money on integrating a super expensive silver bullet like Scalp.

We need air launch low-vis CM in hundreds, so it must be Indian developed. Just need a CM engine and a bigger SAAW.
disha
BR Mainsite Crew
Posts: 8243
Joined: 03 Dec 2006 04:17
Location: gaganaviharin

Re: Tejas Mk2 Medium Weight Fighter: News & Discussion - 23 February 2019

Post by disha »

Indranil wrote: *So, whoever tells you that ADA designers did not know about area-rule, first do a big facepalm. Then tell why they traded off area ruling for lower weight/induced drag and pressure recovery
Thanks for explaining so lucidly. I always knew that the area-rule must have been traded off for something comparably more worthwhile on a small size of Tejas.

Now we know for sure that it is for lower induced drag and better pressure recovery. One thing I might want to add is that Tejas is designed as such to also avoid a turbulent flow into the engine at transonic and supersonic speed. I can think of various things a very turbulent flow can do to fast-moving compressor blades.

At various points, Tejas pilots have categorically stated that the engines are fuel sippers. That is, they have a higher "Kilometers per liter" mileage. I am thinking that the overall design and particularly the inlet design provides a "textbook" airflow to the compressor for the F404-IN to work efficiently.
Post Reply