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

Locked
suryag
Forum Moderator
Posts: 4040
Joined: 11 Jan 2009 00:14

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

Post by suryag »

You too singhaji??
Folks Give some credit to ADA, you think they wouldn’t have thought about mass flow needed for the 414? Most of you can’t even spell A in aerodynamics
nam
BRF Oldie
Posts: 4712
Joined: 05 Jan 2017 20:48

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

Post by nam »

More than ADA, I am worried about IAF. 10 years gives a big opening for MMRCA characters to push in their hardware.

Hope ADA brings out the prototype fast.
gaurav.p
BRFite
Posts: 227
Joined: 04 May 2018 23:02

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

Post by gaurav.p »

^^ suryag saar,

ADA has done a great job, which most of us keyboard warriors can't do. MWF would be great, given that we achieve the targets in time.

EPE in some article is stated to be a low risk project but it hasn't started. I hope it doesn't become the reason just like the sanctions to justify the shortcomings. It isn't coming in Block III super hornets. Possibly, it can be used as quid pro quo for MMRCA2.0. Will stop speculating and wait for the experts opinion.
sankum
BRFite
Posts: 1150
Joined: 20 Dec 2004 21:45

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

Post by sankum »

They are trying to achieve Rafale like metrics
9.5T empty wt+0.8T misc+4.7T internal fuel+9.5T payload=24.5T MTOW.
The misc for Tejas mk1 is 0.8T not 1T. Even if they achieve 8T instead of 7T empty weight for mk2
it will be OK .
Last edited by sankum on 20 Feb 2019 19:35, edited 1 time in total.
suryag
Forum Moderator
Posts: 4040
Joined: 11 Jan 2009 00:14

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

Post by suryag »

Gaurav babu the risk with EPE is a separate topic, my grouse was with the comment that ADA hadnt considered air flow requirements after choosing the 414 while designing the air intake.

Nam ji please look up Toyota or Nissan's car design cycle time and it will be anywhere between 18-24 months. Please give some credit to the CAS when he says he is interested in acquiring 200 MWFs, he would have obviously looked at timelines before saying anything to that effect. Now its a different thing if a new Govt comes in and scuttles the dev with willful players from the forces and DRDO/HAL but as of today the 2023 date for first flight seems fine(would have been vetted out with the customer prior to going public)
brar_w
BRF Oldie
Posts: 10694
Joined: 11 Aug 2016 06:14

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

Post by brar_w »

gaurav.p wrote:^^ suryag saar,

ADA has done a great job, which most of us keyboard warriors can't do. MWF would be great, given that we achieve the targets in time.

EPE in some article is stated to be a low risk project but it hasn't started. I hope it doesn't become the reason just like the sanctions to justify the shortcomings. It isn't coming in Block III super hornets. Possibly, it can be used as quid pro quo for MMRCA2.0. Will stop speculating and wait for the experts opinion.
The Enhanced F414 upgrades are relatively low risk as plenty of risk reduction has been performed funded both by GE and by the US Navy. It is however going to be a costly program when you factor in the actual testing and certification that lies ahead. For this reason, and given the fact that GE is currently locked in GEW III with P&W over adaptive engines in a different category, the company is unlikely to spend its own capital on the project and is likely to wait till the US Navy is ready to invest which could actually be as soon as next year as they solicited cost data on the program from the OEM a few months ago which is usually an indicator that they are trying to slot this in into their near term budgets. Still, I would be more comfortable with the Enhanced F414 being an option for the KF-X and AMCA timeframes than a mid 2020's MK2 timeframe.
Last edited by brar_w on 20 Feb 2019 19:50, edited 1 time in total.
Singha
BRF Oldie
Posts: 66601
Joined: 13 Aug 2004 19:42
Location: the grasshopper lies heavy

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

Post by Singha »

suryag wrote:You too singhaji??
well when the current engine came they were forced to cut holes as the intake was undersized.
nam
BRF Oldie
Posts: 4712
Joined: 05 Jan 2017 20:48

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

Post by nam »

suryag wrote:Gaurav babu the risk with EPE is a separate topic, my grouse was with the comment that ADA hadnt considered air flow requirements after choosing the 414 while designing the air intake.

Nam ji please look up Toyota or Nissan's car design cycle time and it will be anywhere between 18-24 months. Please give some credit to the CAS when he says he is interested in acquiring 200 MWFs, he would have obviously looked at timelines before saying anything to that effect. Now its a different thing if a new Govt comes in and scuttles the dev with willful players from the forces and DRDO/HAL but as of today the 2023 date for first flight seems fine(would have been vetted out with the customer prior to going public)
The comparison with Toyato or Nissan is apple to apple, as they design their product under their own risk. They can control the scope.

Here the scope is controlled by IAF, who can turn around and ask for higher thrust engine if it does not meet their criteria.

Something we have forgotten is that F414 requirement was meant for Navy NOT airforce. IAF has piggy banked on it.

So we have picked up engine first then IAF decided on the loadout!

Regarding airflow requirement, although I hardly claim to be expect, but common sense tells me ADA needs to be aware of the range of airflow to which it will design the intake. Does it know 110KN will meet the requirement? or will it require 130KN?

It cannot create a "generic" intake where all type of thrust range can fit it.
nam
BRF Oldie
Posts: 4712
Joined: 05 Jan 2017 20:48

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

Post by nam »

A layman's question. Would it possible to create a single engine Su30, around a say 200-250KN F414 sized engine?

Assuming tech allows us to create such an engine.
suryag
Forum Moderator
Posts: 4040
Joined: 11 Jan 2009 00:14

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

Post by suryag »

Nam ji - your point being ?? ADA are duffers ..

One of my managers who is now a CEx of some big company paraphrased someone else to the effect of "lets not repeat the past mistakes lets make new ones if at all"

Singha sir, you are presuming that they havent learnt their lessons; although hard to imagine, DRDO/L/ISRO have very stringent annual performance reviews and most likely they have learnt their lessons.

Generally, design activity is a convergence of user aspirations and also available competency. With a task master in the PMO no one can get away with giving fancy spec and not delivering(ACRs are, for want of a better word deliverable linked nowadays). Things have changed considerably
suryag
Forum Moderator
Posts: 4040
Joined: 11 Jan 2009 00:14

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

Post by suryag »

nam wrote:A layman's question. Would it possible to create a single engine Su30, around a say 200-250KN F414 sized engine?

Assuming tech allows us to create such an engine.
Nam ji please put your insightful thoughts in the design your own fighter as i did with a similar question few years ago
nam
BRF Oldie
Posts: 4712
Joined: 05 Jan 2017 20:48

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

Post by nam »

<mod note>Sure Namji please put your questions in Newbie thread or find the "design your own fighter thread" and put it there</mod note>
nam
BRF Oldie
Posts: 4712
Joined: 05 Jan 2017 20:48

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

Post by nam »

suryag wrote:
nam wrote:A layman's question. Would it possible to create a single engine Su30, around a say 200-250KN F414 sized engine?

Assuming tech allows us to create such an engine.
Nam ji please put your insightful thoughts in the design your own fighter as i did with a similar question few years ago
It is not a opinion. A theoretical question for those, who believe can answer it.
nash
BRFite
Posts: 946
Joined: 08 Aug 2008 16:48

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

Post by nash »

If 2023 is timeline of first flight of MWF then it is more logical to order more Mk1A if IAF/GoI want HAL to increase the production to 24/year.
Kartik
BRF Oldie
Posts: 5720
Joined: 04 Feb 2004 12:31

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

Post by Kartik »

SaiK wrote:Video

We’re live first & exclusive with India’s new canard concept — the Medium Weight Fighter (the rechristened LCA Mk.2) https://t.co/2lH3yKiy2u
I’m in love with this design!
chola
BRF Oldie
Posts: 5136
Joined: 16 Dec 2002 12:31
Location: USA

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

Post by chola »

There is a reason why there are heavyweight engines like the F110 or AL-31 for the F-15, F-16, Flankers or J-10 and a medium weight one like the F404/414 or RD-33 for F-18, MiG-29, Tejas or the T/A-50.

The tolerances are different for each weight class. It is like using smaller car engines for larger trucks ir SUVs. Of course you can move the thing with greater RPM but it is not ideal and will wreck the motor in a shorter period in time.

The Tejas with the F414 will blow the doors off performance-wise. I wish we would just concentrate on upgrading it with the new engine.

Again, no one is making a “medium” fighter with a single medium class engine like the F414. You need to go twin like the SHornet or Fulcrum.

And again even a F-16 or J-10 is considered a lightweight fighter. This “medium” designation on one F414 feels a very hard design box we’ve put ourselves into. I have hard time seeing a medium fighter with a lighter engine than the F-16 unless we want something grossly underpowered.

And I am worry about the 120kN EPE coming any time soon. It seems more at the proposal stage than anything else.

http://amp.timeinc.net/thedrive/the-war ... source=dam
General Electric has in the past and continues to propose an improved variant of the Super Hornet’s existing F414 engine. Previous “Enhanced Durability” and “Enhanced Performance” concepts featured new fan and compressor components that would variously improve lifespan and performance. The F414-EPE type reportedly offered a 20 percent boost in thrust.

The Navy did include $15 million for research and development into a Super Hornet engine upgrade in its unfunded priorities list for the 2019 fiscal year. However, this is a wishlist the service sends annually to Congress in the hopes lawmakers will allocate additional funds for various projects.
John
BRF Oldie
Posts: 3447
Joined: 03 Feb 2001 12:31

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

Post by John »

Again even a F-16 or J-10 is considered a lightweight fighter. This “medium” designation on one F414 feels a very hard design box we’ve put ourselves into. I have hard time seeing a medium fighter with a lighter engine than the F-16 unless we want something grossly underpowered.
What is your classification for lightweight fighter something with single engines and any platform with twin engines is Mediumweight fighter? Considering F-16E/F have superior payload and range than Mig-29 i am not sure how you can classify Mig-29 a medium weight fighter and former a lightweight fighter ( i would agree F-16A/B are light fighters but by no means for later variants). I would wait for more facts to emerge before discussing anything on MWF and whether it is under powered but based on what i am seeing it seems to match very closely to Mirage-2000 now (empty weight, thrust and MTOW i suspect for MWF it will be 17.5 not 18.5 as indicated).

To be honest we should have come simply reverse engineered Mirage-2000 which ultimately is what IAF was looking for but simply got lost in translation and requirements were never properly convened. Easier to look back and say that in hindsight.
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

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

Post by Indranil »

Tejas Mk2 is done with inputs from the IAF. There are three basic points that IAF wanted from Mk2:
1. Better transonic and supersonic performance
2. Better STR
3. Better endurance payload

You cannot have all of that with just a 10% increase in thrust. Hence, such an elaborate change. By the way, MWF is very easy on my eye.
1. With the canard, elongated and reshaped body, the plane will have much lower wave drag. Even with the larger body, it will have a drag reduction of about 10-15%. You can see that translated at the top end itself.More details in the write up.
2. The Canard can also allow much better L/D ratio. Again coupled with better thrust, it will lead to significantly better STR. Actually ITR may also go up because they have done lots of tweaks to get better CnBeta performance (the limiter on LCA Mk1).
3. Although they have increased the payload carrying capacity, they have done it judiciously. The wingtips essentially come free. They can carry 11% more fuel externally than the current tanks at reduced drag! In other words, Mk1 with two 1200 ltr tanks has almost the same drag as Mk2 with two 1320 ltr tanks and about 1000 ltr more fuel carried internally. That's huge.

Of course, in the max load configuration, it is a bomb truck. But that is fine with IAF. I don't think they are looking for swing role. They want a lightweight multirole fighter which is nimble in the A2A role, and a can carry a lot of load in the A2G role.

The writeup is ready. It provides details on a lot of subtle changes that are easy to miss. We have handed it over to the publishers, who will take care of it now.
hemant_sai
BRFite
Posts: 173
Joined: 13 Dec 2018 12:13

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

Post by hemant_sai »

Of course my thoughts are all fanboy stuff and in reality I don't have any know how of aeronautics.
I wish MWF all the success and it should become a roaring success.
Last edited by hemant_sai on 21 Feb 2019 11:52, edited 1 time in total.
Indranil
Forum Moderator
Posts: 8428
Joined: 02 Apr 2010 01:21

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

Post by Indranil »

They must be sorry that they can't impress you!
Cybaru
BRF Oldie
Posts: 2904
Joined: 12 Jun 2000 11:31
Contact:

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

Post by Cybaru »

What a gorgeous bird!! Like what they are doing, incremental changes that they can push through testing really fast!

If the EPE engine comes great - otherwise the new 414 is fine. The aim is to reliably and decently deliver the payload. It seems to be well designed for this role! Gripen-vaporware has the same engine too.

Would have loved to see a little bit more internal fuel. 3300 seems like 300 liters more than Mk1. Is that right? Would have been nice if we touched 4000 liters. Would have doubled the airtime when compared to many other birds in IAFs inventory.
Rakesh
Forum Moderator
Posts: 18190
Joined: 15 Jan 2004 12:31
Location: Planet Earth
Contact:

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

Post by Rakesh »

@hemant_sai: I suggest you go and advise ADA of your suggestions. They will take your inputs into consideration.
ramana
Forum Moderator
Posts: 59773
Joined: 01 Jan 1970 05:30

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

Post by ramana »

nam wrote:More than ADA, I am worried about IAF. 10 years gives a big opening for MMRCA characters to push in their hardware.

Hope ADA brings out the prototype fast.
nam, The clearance for MCA shows the Import option is foreclosed and no more dalal netas will come back to power.
That is the strong undercurrent.
ramana
Forum Moderator
Posts: 59773
Joined: 01 Jan 1970 05:30

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

Post by ramana »

nam wrote:A layman's question. Would it possible to create a single engine Su30, around a say 200-250KN F414 sized engine?

Assuming tech allows us to create such an engine.

nam, I don't think so as such an engine will need a large diameter intake to produce 200-250KN. thrust. Lets got to the newbie thread.
naird
BRFite
Posts: 284
Joined: 04 Jun 2009 19:41

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

Post by naird »

ramana wrote:
nam wrote:More than ADA, I am worried about IAF. 10 years gives a big opening for MMRCA characters to push in their hardware.

Hope ADA brings out the prototype fast.
nam, The clearance for MCA shows the Import option is foreclosed and no more dalal netas will come back to power.
That is the strong undercurrent.
Not yet Ramana sir. Not yet. Dalals will give strong fight ! Hope the upper echleons realize this. Every Dalal would have already started evolving counter strategy to MWF;
ramana
Forum Moderator
Posts: 59773
Joined: 01 Jan 1970 05:30

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

Post by ramana »

hemant_sai wrote:I am of same opinion as Chola sir. I was expecting a twin engine with delta frame but front fuselage as derivative from AMCA design. Too many expectations, I guess.
On the second note, if MK2 design is kept so close to MK1, shouldn't they deliver sooner than 2023?
What risk mitigations are planned? If increased weight factor compensates more of advantage of increased thrust? If someone reads MK2 history, which started from 2011, are we still kidding with design only after 8 years?
It is just unbelievable that same ADA which proposes AMCA, is not resourceful enough to impress with MK2.
Also I don't understand why they are not opting for 414 engine on MK1A.
What I can infer is we don't have same kind of leadership in ADA which worked on AMCA.
Taking your first question. MCA is not low tech AMCA.
It is renamed Tejas Mk2. Hence it will be a single engine fighter plane.

2) Even though its derived from Mk1A, it is not same as it needs different fuselage and canards. All these aerodynamic changes will need to be tested out to full range. So takes time. besides 2023 is not that far. its three year program. Quite fast if you ask me.

3) The fact that its a evolution of the Mk1A design shows risk mitigation is in place. The increased thrusht along with drag reduction gives more agility and capability.
Concept studies started in 2011 and not full scale development. Now don't sound like Col Shuklaji.

4) Has two questions in a condescending manner wont bother giving an answer. What has AMCA got to do with Tejas Mk2?
Your last question deserves a warning for you are disparaging from misperception.
I suggest you go back and edit your post.


SuryaG if the post is not edited please give a warning.
Thanks.ramana
ramana
Forum Moderator
Posts: 59773
Joined: 01 Jan 1970 05:30

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

Post by ramana »

naird, Right on cue LMT comes up with vapor ware F21!
Rishi_Tri
BRFite
Posts: 520
Joined: 13 Feb 2017 14:49

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

Post by Rishi_Tri »

Indranil wrote: The writeup is ready. It provides details on a lot of subtle changes that are easy to miss. We have handed it over to the publishers, who will take care of it now.
Link please whenever available. Thanks.
sahay
BRFite -Trainee
Posts: 66
Joined: 11 Apr 2017 19:45

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

Post by sahay »

ramana wrote:The clearance for MCA shows the Import option is foreclosed
I don't think the import option is foreclosed. IAF is at 31-32 squadrons now, with 6 squadrons of MiG-21 and 3 squadrons of MiG-27 yet to be retired. If we count 1 squadron of Mk 1, 4 squadrons of Mk 1A, 2 squadrons of Rafale, 1 squadron of MiG-29 and 3 squadrons of Su-30MKI that are to be acquired, it'll just add 2 squadrons after MiG-21 and MiG-27 retire. There's no way the IAF will be okay with just maintaining the strength at 33-34 till 2029.
chola
BRF Oldie
Posts: 5136
Joined: 16 Dec 2002 12:31
Location: USA

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

Post by chola »

John wrote:
Again even a F-16 or J-10 is considered a lightweight fighter. This “medium” designation on one F414 feels a very hard design box we’ve put ourselves into. I have hard time seeing a medium fighter with a lighter engine than the F-16 unless we want something grossly underpowered.
What is your classification for lightweight fighter something with single engines and any platform with twin engines is Mediumweight fighter? Considering F-16E/F have superior payload and range than Mig-29 i am not sure how you can classify Mig-29 a medium weight fighter and former a lightweight fighter ( i would agree F-16A/B are light fighters but by no means for later variants). I would wait for more facts to emerge before discussing anything on MWF and whether it is under powered but based on what i am seeing it seems to match very closely to Mirage-2000 now (empty weight, thrust and MTOW i suspect for MWF it will be 17.5 not 18.5 as indicated).

To be honest we should have come simply reverse engineered Mirage-2000 which ultimately is what IAF was looking for but simply got lost in translation and requirements were never properly convened. Easier to look back and say that in hindsight.
Point noted on the F-16 E/F but my impression from the deployment of the larger air forces — light, medium and heavy roughly correspond to:

1) Light (one F110 or AL-31 class engine) — F-16, J-10

2) Medium (two F404/RD-33 class engine) — F-18, MiG-29, FC-31, KFX, Rafale, Typhoon

3) Heavy (two F110/AL-31 class engine) — F-15, Flankers, J-20, F-22

Of course, there are the really light combat aircraft of the world with a single F404 class engine and Unkil’s F135 ultramodern single engine for the F-35 to replace all classes. These are rather outliers. The Koreans are using a single F404 for a trainer.

You’re right. Better to wait. But it seems better to me to upgrade the MK1A to the F414 and look at MWF with a heavy weight engine — AL-31(we make a substantial percentage of this engine for the MKI) or F110. A base Tejas with the F414 would be a world beater IMO. Anyhoo, just my thoughts.
souravB
BRFite
Posts: 630
Joined: 07 Jun 2018 13:52

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

Post by souravB »

chola wrote: You’re right. Better to wait. But it seems better to me to upgrade the MK1A to the F414 and look at MWF with a heavy weight engine — AL-31(we make a substantial percentage of this engine for the MKI) or F110. A base Tejas with the F414 would be a world beater IMO. Anyhoo, just my thoughts.
Sir, during design a compromise is made between available power and range. Base tejas being a small ac inherently carry less fuel and putting a bigger engine into it would decrease its range. Till the time it is meeting it's performance goals, it should be okay with F404. MWF OTOH is supposed to be a M2000 class fighter and M2000 has an engine of F414 class.
Mk1A should be okay with F404 for now, for MLU, one can think about having an enhanced engine whether it be F414 or Kaveri.
Rakesh
Forum Moderator
Posts: 18190
Joined: 15 Jan 2004 12:31
Location: Planet Earth
Contact:

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

Post by Rakesh »

https://twitter.com/SJha1618/status/1098296685023744000 ---> Ok, as far as the Tejas Mk-2 'Medium Weight Fighter' is concerned it seems the user has requested that the SCALP air to surface missile be integrated with it.
Rakesh
Forum Moderator
Posts: 18190
Joined: 15 Jan 2004 12:31
Location: Planet Earth
Contact:

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

Post by Rakesh »

Looks like the Tejas Mk2 model got a weapon load out. Please drag & drop the picture into a new browser window for larger view.

The model is different from yesterday's post (viewtopic.php?f=3&t=7636&p=2322362#p2322362), which had no weapons.

I see SCALP in the centreline, which ties in with Saurav Jha's tweet in the post above. Four air-to-air missiles on the right wing, so a total air-to-air missile load out of 8 missiles. Very Nice! :)

https://twitter.com/DECATRIX/status/1098200767230406656 ---> Finally the scaled model of the Medium Combat Aircraft revealed. Very similar to the Mk I. Grown larger, with canards, projected refuelling probe, dual rack pylons and wing tip pylons.

https://twitter.com/DutchAviaPhoto/stat ... 0750547968 ---> Tejas Mk2 gets canards, big payload boost.

Image
Rakesh
Forum Moderator
Posts: 18190
Joined: 15 Jan 2004 12:31
Location: Planet Earth
Contact:

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

Post by Rakesh »

Tejas Mk2 gets canards, big payload boost
https://www.flightglobal.com/news/artic ... oo-455948/
The extra length changed the fighter’s center of gravity, requiring the addition of a forward lifting surface. The ADA looked at a number of options, including leading edge extensions, but finally decided on canards, which also help with maneuverability. The new aircraft also sees improvements made to the fighter’s delta wing.

“The forward canards help in other areas too,” says the official.
Kartik
BRF Oldie
Posts: 5720
Joined: 04 Feb 2004 12:31

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

Post by Kartik »

sankum wrote:7T is the intended empty weight as MTOW 17.5T and payload of 6.5T for clean weight of 11T.
Minus 3.3T internal fuel and rest 700kg for 2CCM, pilot weight, cannon ammo, chaff, flare and pylons.
Yes, it would seem that 7,000 kg is the target empty weight if they intend to carry full fuel load AND full payload at the same time. It's very ambitious- my prediction was in the 7400 kg range, but this 7,000 kg figure needs to be validated by someone at ADA. JayS, can you please try to get some info on the target empty weight?

7,000 would be a full 1,000 kg lighter than the Gripen E's empty weight of 8,000 kgs.

While a lot of learning can be applied from the Mk1 on what structures' weight can be reduced, only increasing the empty weight of the MWF Tejas Mk2 by 350 kgs over the Mk1, while strengthening the wing to take the additional payload, adding new internal fuel tanks and new canard surfaces seems to be a very difficult task.

I would be very happy if they managed to attain ~7400-7500 kg empty weight. That would still allow the MWF to take off with 6500 kg of weapons payload and not full internal fuel, and then refuel in mid-air. Anyway, 90% of the MWF's missions will be with take off weight lower than MTOW.
Kartik
BRF Oldie
Posts: 5720
Joined: 04 Feb 2004 12:31

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

Post by Kartik »

chola wrote:There is a reason why there are heavyweight engines like the F110 or AL-31 for the F-15, F-16, Flankers or J-10 and a medium weight one like the F404/414 or RD-33 for F-18, MiG-29, Tejas or the T/A-50.

The tolerances are different for each weight class. It is like using smaller car engines for larger trucks ir SUVs. Of course you can move the thing with greater RPM but it is not ideal and will wreck the motor in a shorter period in time.

The Tejas with the F414 will blow the doors off performance-wise. I wish we would just concentrate on upgrading it with the new engine.

Again, no one is making a “medium” fighter with a single medium class engine like the F414. You need to go twin like the SHornet or Fulcrum.

And again even a F-16 or J-10 is considered a lightweight fighter. This “medium” designation on one F414 feels a very hard design box we’ve put ourselves into. I have hard time seeing a medium fighter with a lighter engine than the F-16 unless we want something grossly underpowered.
I don't agree whatsoever. What is clear is that the IAF is targeting the basic specifications of the Mirage-2000, with slightly higher MTOW and lighter empty weight, which they may consider as doable thanks to much greater composite content in today's fighters, and a lighter engine.

This design is clearly sized to fit that niche. the M53-P2 on the Mirage-2000 produces 95 kN of thrust in afterburning mode, and to date no other higher powered Mirage-2000 exists. It weighs 1580 kg, which is at least 250-300 kgs heavier than an installed F-414-INS6 will be.

One thing people will always forget is that the bulk of the missions that the MWF will undertake will be with the take off weight at much lower than MTOW weight.

-Air to air superiority missions will only see missiles and drop tanks. No massive bombs, PGMs or ALCMs.
-Swing-role missions also typically see a balanced loadout, with fuel and payload mix done in a way that it doesn't make the fighter a lumbering brick. I mean how many times have you even seen a Mirage-2000 loaded to the gills with bombs and missiles?
-for those few long range missions where the MWF will need to be fully loaded with both bombs and self defence missiles plus full internal fuel, the fuel starts to get used up and the jet gets lighter as the mission progresses. And anyway, it would be escorted by fighters only tasked to engage enemy fighters.

You guys are talking like the MWF will ALWAYS take off with 17,500 kg mission weight and STAY at that weight throughout the mission.
Singha
BRF Oldie
Posts: 66601
Joined: 13 Aug 2004 19:42
Location: the grasshopper lies heavy

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

Post by Singha »

6500kg is weapons is a absurd number!
What mission and loadout needs this?

For a dpsa mission 4x450kg a2g weapons 2 supersonic drop tanks and 2 aams is probably it and a LDP if laser pgm

When you multi rack lot of small weapons like ngarm asm sant saaw weight will be at or below the above for tactical strike mission

Same for dca linebacker role with 8 aam and 2 supersonic drop tanks
Singha
BRF Oldie
Posts: 66601
Joined: 13 Aug 2004 19:42
Location: the grasshopper lies heavy

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

Post by Singha »

In a2a role it will be formidable performer with 6xastra1 and 4xasraam whose specs are more like mica ir than a small short lived diwali rocket
fanne
BRF Oldie
Posts: 4282
Joined: 11 Feb 1999 12:31

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

Post by fanne »

I wonder if LCA mk2 can do all this, what will SU30MKI, Jags and Mirag200 upg will do (maybe the plan is to retire them or maybe run CAP over our bases while valiant LCA-MK2 flies 1000s of KM with full load and bomb Quetta or deep in Tibet)?
Kartik
BRF Oldie
Posts: 5720
Joined: 04 Feb 2004 12:31

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

Post by Kartik »

Indranil wrote:Tejas Mk2 is done with inputs from the IAF. There are three basic points that IAF wanted from Mk2:
1. Better transonic and supersonic performance
2. Better STR
3. Better endurance payload

You cannot have all of that with just a 10% increase in thrust. Hence, such an elaborate change. By the way, MWF is very easy on my eye.
1. With the canard, elongated and reshaped body, the plane will have much lower wave drag. Even with the larger body, it will have a drag reduction of about 10-15%. You can see that translated at the top end itself.More details in the write up.
2. The Canard can also allow much better L/D ratio. Again coupled with better thrust, it will lead to significantly better STR. Actually ITR may also go up because they have done lots of tweaks to get better CnBeta performance (the limiter on LCA Mk1).
3. Although they have increased the payload carrying capacity, they have done it judiciously. The wingtips essentially come free. They can carry 11% more fuel externally than the current tanks at reduced drag! In other words, Mk1 with two 1200 ltr tanks has almost the same drag as Mk2 with two 1320 ltr tanks and about 1000 ltr more fuel carried internally. That's huge.

Of course, in the max load configuration, it is a bomb truck. But that is fine with IAF. I don't think they are looking for swing role. They want a lightweight multirole fighter which is nimble in the A2A role, and a can carry a lot of load in the A2G role.

The writeup is ready. It provides details on a lot of subtle changes that are easy to miss. We have handed it over to the publishers, who will take care of it now.
Very good post IR. Can't wait to read your article on this beauty. :D

I fully agree with your assessment. The jet's design is perfectly balanced in my opinion. The wing area, which was massive on the Mk1, now seems to be perfect for the length of the fuselage. The placement of the canards would have been quite tricky, given the wing stub join near the middle of the airframe and the lack of room for it to rotate to the desired degree. I feel that the area ruling improvements that were made around the canopy area (the bigger volume right behind the canopy), plus the forward fuselage elongation made it possible to mount the canards, while allowing the pilot to access the cockpit and not block his entire view downwards.

Basically to a trained eye, it is obvious that plenty of optimization has gone on to get this configuration right..and have they got it right or what!

The other points you made are gems. The drag reduction figures would've been validated in wind tunnel tests and CFD analysis, akin to the studies that we had discussed on this forum earlier.

But your access to this data is revealing the MWF to be THE fighter the IAF wanted all these years. It's Mirage-2000 equivalent with tech infusion that will keep it relevant for 3 more decades.

Now its up to ADA to meet the design goals in terms of weight management. The rest can be achieved, as they have already proven a lot of it on the Mk1.
Locked