Bharat Rakshak

Tellis Strongly recommends Tejas for IAF. Saab future uncertain

According to ASHLEY J. TELLIS, a senior associate at the Carnegie Endowment, current configuration of Gripen/NG is very attractive and many may consider it to superior to India's own Tejas program. However, he cautions that selecting Gripen/NG would be a wrong move as Saab future as an independent manufacturer does not look promising. [He therefore highlights the need for Tejas and ability of india to upgrade to its heart content.]



source: http://carnegieendowment.org/files/dogfight.pdf

I am very tired of this "it will fly when it flies", yeah yeah i know the difficulties but it would be nice to see lsp6/7/8 flying by March-April(which i think was what PS promised last)

oh please, tellis strongly recommends JSF rather LCA. check his numbers for his vision IAF 2030

Lalmullah strongly recommends a mixed force of lalchix and white ghagra chix
there, that should make the newspaper headlines, just like ashleybhai

The JSF is in such trouble (AWST reports) that the US is armtwisting its allies and India into buying more F-16s/F-18SHs instead until the JSF finally arrives.Oz has bought 40+ SHs for the moment."Tell-us" is simply touting US wares.The cost of the JSF after the British/RN's savage budget cuts has dumped the STOVL version into te sea with barely a handful (14?) JSFs on order! The cost of one JSF has now been estimated as being not less than $130 million! For that price,one would get three MIG-35s or Gripens and 4-5 LCAs instead! Moreover,a single-engined JSF is more at risk in carrier ops at sea than a twin-engined fighter.With the late arrival of the JSF, not on the horizon yet ,with more US allies getting disillusioned about buying it,the US is desperate for a new sucker,so presto!......here comes India again,after saving Boeing's bacon with 10+6 C-17s already sold to it!

Tell-us is telling us to buy Tejas because he knows and we know how much futher the work on MK-2 has to be done and just how limited prodution will be by 2020.The very attractive "most bang for the buck Gripen" poses the greatest threat to the US in the emerging markets with S.Arica,Thailand,Romania and others operating it or lusting ater it (Brazil).Therefore the war against the Gripen has ebgun by the US.Expect more mud to be thrown at it by "tell-alls" like Tell-us!

Agree 100%. This is nothing more than lifafa journalism from folks getting desperate and frustrated after hearing the stories about the Euro canards getting ahead.

This also scares me, because these guys can go to any levels of "Saam, Daan, Dand, Bhed" to get business, and our greedy, cunning, self serving powerful elite of India are an ever-ready lot...

in a $10B deal, one must expect atleast $500m-$800m to wash around and get soaked up

it was expected to deliver a squadron by 2013 i donot know whether LSP are also included in that

1 sq means - 20 or 18 aircrafts ? little bit confusing

for single seater fighters, 16+2 type trainers is the usual strength. 2 additional single seaters per sqdn are allocated as attrition reserve but I'm not sure if these are held by the sqdn itself.

thanks,
so roughly 20 per sq

Attrition reserves are not held by the Squadron. So its 18. More often than not, there is always a shortage of the type trainer - so in real sense, a squadron would end up with 16+1 or even 15+1, even though its establishment on paper is 18

well Radia tapes indicate that 15% cut is quite common...

sure, but size of deal sometimes imposes caps on %age deductions

The LCA order is 20 + 20. So that will make 4 squadrons with 18 aircraft each plus 4 attrition reserves. For the MRCA however there appear to be no attrition reserves. 7 squadrons, 18 aircraft per squadron makes 126 exactly.
Edit: Appears to be same for the MKI. Eventual numbers will be 270. That makes 15 squadrons exactly at 18 per squadron.

I dont understand Ashley Tellis Locus standi in writing the report? He a US citizen and an ex-US official is writing an advice report for IAF to implement. How proper is that? And how proper of Indian officials to give him inputs? Are they retired or in office?

from the pdf

Check @1:25, the mirage crossing the exhaust of the lead mirage involuantarily enters into a roll when the right wing catches the high speed jetwash. IMHO the roll is uncommanded. Indeed Tejas needs to clear those tests before formation/combat flying.

Link fixed


Cheers....

basic question...how would they perform a wake penetration test? I mean the aircraft needs to be subjected to different "wake" profiles right? how would they create the "wake"?

^^^ Guys but i think i had seen a video of two white tds taking off in quick succession, if thats true, what more does wake penetration entail ?

By flying an aircraft in front of course! How else? And then test whether you can enter from right behind, from top to bottom, diagonally, bottom to up, enter while turning, different altitude, speeds etc!

Whatever we do with Snecma and DRDO, the design goals for the Kaveri to come out of the JV should be crystal clear, technology level wise, I think what we should aim for is this.

1) All blisk compressor stages.

2) TeT at around close to 2000k, an overall pressure ratio of 30:1 and a T:W ratio of 10:1

3) Contra rotating spools

4) Cutting edge HPT and LPT turbine materials with Thermal Barrier Coatings.

Some 4000 hrs of service life and a thrust growth potential of upto 125 KN, probably entering with around 100KN thrust.

If that happens, it will all have been worth it, including the K-9 learning experience and everything. We will end up having an engine that is among the best possible and comparable to anything anywhere in the world.

This is perhaps what GTRE is after now.

Vina, I must say I am a big fan of yours. I like to read your posts and eagerly wait for that.

i was reading some of the messages posted about the gripen earlier this week about what a wonderful aircraft it was and how quickly the NG was developed and about the wake penetration test crash. After doing a bit of digging on uncle google, I came to a wikipedia page about the gripen crashes.
http://en.wikipedia.org/wiki/Accidents_ ... _39_Gripen

Interestingly there have been several (5) crashes of the Gripen A/B/C/D till now, and after reading through them, I see that 4 of them are due to some aircraft problem and the fifth is due to inadequate training.

Interestingly two of the crashes are due to pilot induced oscillations (PIO) would this be classified as what the IAF would call "Pilot Error"? (does anyone here know), i was just wondering about all the marketing material talking about "care free handling", FBW will not allow the pilot to do anything that could damage the aircraft, etc etc....
What happened to the super duper FBW and computer controlled logic etc during these crashes?

Very interestingly, one of the crashes was due to an incorrectly placed ejection handle!!!, what happened to all the great Swedish ergonomic prowess?
Let us take all the marketing speak with a pinch of salt, what is to say that the NG is a perfect plane already and that there are no flaws waiting to be found.

Think about what would happen to the LCA if we have even one crash even at this stage (i hope that it does not ever happen). At the end of the day there is no use claiming that the electronics and computer control will not have any flaws because any system this complicated will have bugs and flaws that are hidden until something happens and a detailed investigation will find them.
These are fighter aircraft, they are built to the edge of existing (or known) technology, to the very edges of existing manufacturing technology and tolerances, so any such incident should not be the reason for great panic or alarm. They should be treated as an opportunity to find out what went wrong and what can be done to prevent it from happening again.

Anyways time to end my rant, "Shit happens to anyone and everyone, how they deal with it and what they learn from it, shows what they are made out of". I have to say that the LCA team has had a lot of shit happen to them and they have learned, adapted and come through with flying colours.

I just see a blank grey spot where the video should be....

Please provide link..

If you put the spec premium that high you can be assured that GTRE Kaveri will never achieve it in the next 15 years and it will be Kaveri redux , Snecma AFAIK does not have those kind of 10:1 rated engine tech and will never part with its tech even if they achieve those with some variant of M-88

A reasonable spec of GTRE-Snecma JV is to develop an engine with T/W ratio of 8-8.5:1 and a A/B thrust of 90-100 KN in the next 5 -8 years that is good enough to power the Tejas.

@Gurneesh

Link fixed in the original post.

Cheers....

What an enchantingly beautiful video!

Indeed saar, but don't tell me that you haven't seen this movie!

Cheers....

PIO is a control system design fault that needs to be fixed. And mind you they were using an "off the shelf" FBW/FCS, which is a straight lift from the F-16

This the current state of art. Snecma has all the components for those with it (blisks, high temp materials and the design and development tools). I am not asking for the NEXT gen stuff like Metal Matrix Composite fan blades etc which is their contribution to the LEAP-X program with GE for CFM!



With the 414 putting out 100kn, a replacement engine with a thrust less than an outgoing one and that too with the inevitable in service weight gain is a non starter. 100 KN will be the min and if the achieve that with a 10:1 T:W ratio (around the weight of the current EJ200 with 90KN thrust), it will be great.

Shiv Saar,
That clip is from the movie Sky Fighters. The whole movie is 102 minutes of non stop footage like that. Even the opening credits are a treat to watch. If some relative from videsh can send you the Blu Ray print, you would really enjoy 102 minutes of 1080p awesomeness. Believe me, the clip is not even the high point in the film.

Snecma will not give us any TOT or any thing like that ( even with so called Deep TOT including SCB we got with AL-31FP we never made any gains that would help Kaveri in any way ) , what they will do is design and test and flight qualify the engine for Tejas Mk1/new Kaveri and then we end up paying royalty and import core stuff from them ( something if you would recollect IAF was not happy with GTRE-Snecma venture ) , I think this Snecma-GTRE venture will be like Brahmos venture where both sides design and get their stuff for Kaveri and then it would be labeled as new Kaveri.

What is NEXT GEN is also relative to where you stand in Engine Technology , for the Goras the Metal Matrix Composite blade,Geared Turbofan and other ding dong will be Next Gen that would power a A-350 or Dreamliner but for us to make Kaveri reach a T/W ratio of 8 or 9 and Thrust of 90-100KN will be Next Gen that we can look up to in the next 7-8 years.



Ejactly and hence no one in official circle is even talking of Kaveri ever powering a Mk2 or Mk3 Tejas or for that matter Tejas at all , they ( either the IAF or DRDO or both ) have raised the bar for the engine to an extent that nothing besides some latest and greatest from GE 414 series will be powering the LCA during its entire life time , like it did with Tejas with in Mk1 avatar.

IF ever the GTRE-Snecma Kaveri reaches to a stage of flight qualified engine they would at best power couple of Tejas Mk1 prototypes with it and as they are telling us Kaveri will power the next gen fighter AMCA.

Austin ji, nothing like that is projected on the media, and your thoughts may not be true afaik. What snecma is saying to reuse its ECO core, and has openly said, it would be a waste of money to re-invent wheel, and things like that. The point is their core will never get 100kN, and IAF has categorically rejected Snecma for Tejas.

Now, why collaborate with them, when GTRE can on its own terms and project schedule complete a 100kN one. yay!

While IAF in the interim years, be satisfied with 414 IN versions. Why this billions of $$ waste on France?, where they are least bothered (per oped links) to accept terms of the requirements. We are not idiots to consider billions wasted to use their cores if it has deficiency. Kabini must be made to deliver 100kN, no matter redesign, re size or change configurations. Now, GTRE can't say they can't after they have already going successful now.

This learning experiences can never be purchased. French will take the money, and will not deliver. Scrap the Snecma-GTRE deal that is a total waste. We can't afford that both at project aspect and requirements aspect, leaving economics on the pain side.

vina, What is the concern about wake penetration flights? is it the back wash will be random and how does the aircraft react to the random back wash? If the preceding a/c is supersonic the wake will be in straight lines and the backwash have less air density?

SaiK what makes you feel if GTRE cannot develop a decent flight qualified engine for Tejas Mk1 will develop a 100KN engine on its own that would match 414 if not exceed it ?

Tejas fate with GE engine was sealed when they decided to fly its prototype and production Mk1 with GE-404 variant and then it was quite easy to see why they would choose 414 over any thing out there , much like Gripen , Tejas in its current and new avtar will always be GE engine for production model.

Most likely then not , IAF will not waste its time to flight qualify a new engine like Kaveri for Tejas in production model ,as long as GE 414 is available to them , Kaveri would in all likelyhood will power AMCA in production model and perhaps in prototype if its available by then.

agreed. My issue is not GE414 for mk2, but having to collaborate with Snema. Why do we need snecma at all? GTRE is not time pressured at all here from requirements to delivery. Let them graduate, as a baby with some defects would.

--
I found an interesting presentation of 1st typhoon's wake penetration for high speed and high loads.

http://www.ukintpress-conferences.com/c ... schwab.pdf

From K Prasad ji on AI2009 thread


Hope the above happens sooner

Well, the wake is highly turbulent ,is highly unpredictable and unstable stuff and usually has stuff like eddies and vortices. This not the normal state for which any airplane is designed for (look up any text book, some nice undisturbed air flowing in nice streamlines with no mixing of layers (laminar flow)..Problem with an unstable plane like the LCA is that the FCS has to handle these transients and extremes which are "off normal" and stablize the plane. That will require testing and serious testing at that.

For eg, next time you go to a lake and take a boat ride, try crossing the wake of another boat at right angles. As you do, your boat will bob and weave and experience some crazy motions. Even if you travel in the wake of the boat ahead, you will experience funny motions that you wont in still water. The boat is stable by itself and the instabilities of the way are within limits of the stability of the boat design and it rides it out. What if the boat were artificially stabilized like the LCA is ?

So its like a stress test on steroids of the flight control systems essentially? I understand the very nature of the test is to put the plane(+software) through its paces. In such a case, how do they handle safety? As in, like AoA testing is done by gradually increasing the AoA each time and poring over how the plane has handled it before pushing it even more. Any idea how wake testing is done? Would be interesting to know. Thanks!

From the PDF:

Test Objectives Wake Penetration

• Verification of the robustness of Air Data System and Air Data Transducers (ADTs) against wakes.
• Validation of a combined wakes and flight mechanics model of flight mechanics department.
• Verification of the robustness of the FCS (Control Laws) against wakes.

Cheers....