ADA Tejas (LCA) News and Discussions

[ersakthivel]

Contacted a friend and found out something what I always mentioned. The F-414s ordered are not EPE. It is a derivative engine.

Anyway, things don't seem to be particularly hot on the schedule. ADA's current schedule of getting Mk2 flying by 2014 and IOC by 2016 is overly optimistic and will not be reached at the specs that IAF is demanding for. It may take that long just to certify the new engine on LCA. So flight testing may happen only after 2016.

Yeah, the Navy has a requirement for the EPE on their version. This was established partially through a news paper article a few months ago publicly. But even the developers are not entirely sure as of today. So, lets see what happens here.

Did your friend tell you anything about the auxillary air intake on LSp-7?And how much it will improve the top speed?

If you had a friend in ADA why were you insisting for the past two years
1.LCA has never crossed mach 1.4,
2.It never exceeded AOA of 16 degree
3.It is subsonic at sea level.
4.And it's radar had a detection range of 120 km and tracking range of 80 km,
while the truth was
1.LCA has crossed mach 1.6 even before the first flight of LSP-7( without the aux intake in LSP-7).
2.It has exceeded AOA of 22 degree without the aid of further flights from LSP-6 which was tasked with improvement of AOA
3.And it went past mach 1.2 at sea level
4.While the radar that was placed on LSP-3 itself had detection and tracking range of 120 km as per VAYU article and WIKI.


The 98 kn for tejas mk-2 is enough as it was design spec initially .

But when 108 kn engine is available it is upto airforce and ADA to make a choice.

When the navy openly indicates it wants 120 kn epe , why doesn't the airforce want this extra thrust of even 108 kn is a mystery to me especially when boeing india chief VIVEK LAL himself has said that baseline EPE version is available for indian LCA. .

 

[ersakthivel]

Contacted a friend and found out something what I always mentioned. The F-414s ordered are not EPE. It is a derivative engine.

Anyway, things don't seem to be particularly hot on the schedule. ADA's current schedule of getting Mk2 flying by 2014 and IOC by 2016 is overly optimistic and will not be reached at the specs that IAF is demanding for. It may take that long just to certify the new engine on LCA. So flight testing may happen only after 2016.

Yeah, the Navy has a requirement for the EPE on their version. This was established partially through a news paper article a few months ago publicly. But even the developers are not entirely sure as of today. So, lets see what happens here.

WHAT IS THE TOP THRUST OF THIS DERIVATIVE EPE ENGINE?


Also does the INS6 denote a total of Stage-6 and a wide swept fan(in case if it is a EPE derivative) ,in place of normal 7 stage Ge-414 engine with a regular fan and lesser thrust of older 98 kn GE-414 engine?


Will it have just 6 stages and wide swept fan with a top thrust of 108 kn as DECKLANDER said or not?


Didn't your friend tell you anything about ADA chief SUBRAMANIUM's interview to AJAI SHUKLA in which the chief has said
1.LCA mk-2 will have interfaces to fire any long range missile that will come with MMRCA contract(METEOR is the only long range BVR with raflae)

2.And the flight envelope of mk-1 was opened only up to 85 percent and it reached mach 1.6 and 6Gs within that flight envelope.

3.ALso if tejas can reach mach 1.6 at just 7.5 km that too with an inadequate intake carrying LSP-4 or 5, what top speed the designers of tejas are aiming for with the new aux air intake in LSP-7?

4.Did he also tell you that it was tested up to 13Gs in static test rigs at ground?

5.Did he tell you anything about the new demand from IAF in 2004 for the induction of higher weight long range BVRs ,which led to weight increase because of the wing was strengthened to carry those heavier missiles which will impart a higher stress on wing when fired from the wing with higher momentum?

6.Can your friend tell us whether tejas ha a bigger radome dia or not?

If you can get answers from your friend for the questions raised in this post and above post we all will know the exact picture regarding tejas.

Thanks in advance.

 

[Decklander]

F414EPE is a testbed engine with ability to produce 120KN thrust. This thrust will be increased to about 128Kn later. The F414-INS6 is a derivative of this EPE engine which will be the production engine with option to have any thrust figure from 90Kn to 118KN. GE is offering it as 108KN as this is what F-18SHs require. Everytime you get an engine rated to higher thrust levels, a lot of cost is involved and certification is itself time consuming.SO MK2 will get it rated for 108Kn with derate of 98KN. For IAF version 108Kn is too much of thrust but for IN its not as you need nearly TWR of 1:1 for skijump launch to be able to carry full load.

When I say it will be EPE engine, I mean that the engine will be using all tech from EPE engine and not from present F414-400and can be rated to 120KN.

 

[Decklander]

Regarding airframe certification of LCA, To be rated for 9G limits the airframe must withstand 33% higher loads. So for 9G rating the LCA airframe must not have failure of any componant of the airframe below 12G loads. 13G load was the breakup point load when some part of airframe gave way under stress. So LCA is now cleared for+9G loads. The static testing is a way to stress the airframe to make it break apart. The loading is countnuously increased til it breaks. It is also the break up loads.
IAF had initially wanted only +8g load, than they increased it to +9g, that involved further strengthening of airframe and so increased the weight of the LCA. The increased weight + higher G load needed higher thrust so the F404-IN20 (F404 version for INdia with 20K thrust)too became under powered.
ADA and HAL wud have delivered this ac long long back had it not been for the officers of IAF who on instructions from MOD have changed the specs many times in their effort to kill this project. The Specs for MK2 have now been fixed not bcoz of IAF but bcoz of IN who have now taken a Pivot position on the development of this aircraft.

 

[ersakthivel]

Regarding airframe certification of LCA, To be rated for 9G limits the airframe must withstand 33% higher loads. So for 9G rating the LCA airframe must not have failure of any componant of the airframe below 12G loads. 13G load was the breakup point load when some part of airframe gave way under stress. So LCA is now cleared for+9G loads. The static testing is a way to stress the airframe to make it break apart. The loading is countnuously increased til it breaks. It is also the break up loads.
IAF had initially wanted only +8g load, than they increased it to +9g, that involved further strengthening of airframe and so increased the weight of the LCA. The increased weight + higher G load needed higher thrust so the F404-IN20 (F404 version for INdia with 20K thrust)too became under powered.
ADA and HAL wud have delivered this ac long long back had it not been for the officers of IAF who on instructions from MOD have changed the specs many times in their effort to kill this project. The Specs for MK2 have now been fixed not bcoz of IAF but bcoz of IN who have now taken a Pivot position on the development of this aircraft.

This same circus is repeated in AMCA again.Last heard a final ASR of 16 to 18 ton aircraft has been given.First a 25 ton MTOW was mentioned, then a 20 ton MTOW was mentioned in second ASR, Now in august last year a 16 to 18 to MTOW is being mentioned as final ASR, from 2001 to 2012 chinese have test flown a stealthe airframe , but IAF could not finalize the ASR!!!!!

Instead of a sensible option of evolving the airframe of tejas into AMCA the IAF is repeatedly revising ASRs from 2005 to 2011 three times and even now a final version of ASR has been finalized or not is the issue.

 

[ersakthivel]

Came across the Honeywell presentation for Jaguar upgrade. Wow, that is some serious capability boost !!

-236kg reduction in empty weight.
-2000kg gain in payload.
-23%reduction in take off distance in hot and high conditions
-faster climb rates to 6000m altitude
-36% extension in range
-engine capable of auto restart
-plenty of factors easing maintenance (the video features a clip of engine change)

Couple it with the modifications covered here and its a whole new bird.

If jag can be upgraded with more powerful engines and more payload capacity ,more range,faster climb rate,what prevents LCA mk-1 from getting upgrades like this in future?

 

[ersakthivel]

ame across the Honeywell presentation for Jaguar upgrade. Wow, that is some serious capability boost !!

-236kg reduction in empty weight.
-2000kg gain in payload.
-23%reduction in take off distance in hot and high conditions
-faster climb rates to 6000m altitude
-36% extension in range
-engine capable of auto restart
-plenty of factors easing maintenance (the video features a clip of engine change)

Couple it with the modifications covered here and its a whole new bird.


If jag can be upgraded with more powerful engines and more payload capacity ,more range,faster climb rate,what prevents LCA mk-1 from getting upgrades like this in future?

Some of the pictures below are from an airbase in rajasthan where tejas went for some trials.The aux air intake is there on this bird .So it must be LSP-7

 

[ersakthivel]

The fruits of LCA for the Indian aerospace program are ripening. BEL has announced that it is developing EW suites, with DARE (DRDO) for the Jaguar, Su-30 and MiG-29.


The Jaguar IM radome is smaller and at best it may offer around the level of 40 km to 60 km detection range for A2A targets; So this upgrade is not intended to make JAgs a serious A2A birds instead it improves their self defence capability during strike roles. SO even with the upgrades it is no way comparable to TEJAS MK-1.

 

[ersakthivel]

Air chief NAK Browne today said the IAF has identified a "design flaw" with the Russian-made supersonic fighter aircraft Sukhoi-30 though nothing is wrong with its "airworthiness". "We have identified a Fly-By-Wire problem with the aircraft. It is a design issue and we have taken it up with the designing agency," he told reporters on the sidelines of a function held to mark Golden Jubilee celebrations of Armed Forces Medical College (AFMC) here.

Referring to the December 13, 2011 crash of a Sukhoi-30 MKI fighter aircraft near here, the Air Chief said that more checks were being implemented to ensure that such incidents do not happen again.

The aircraft had crashed at Wade Bholai village soon after it took off from Lohegaon air base. Two pilots of the fighter plane managed to bail out safely.

"There is nothing wrong with the aircraft or its airworthiness. I have myself flown the aircraft," he said.

This is how complex the fly by wire tech is, especially even more tough for full relaxed static stability fighter programs.

So sukhoi must be flying with some limitations till corrected I think.

Even very experienced sukhoi design team has to be told by IAF pilots about this after a decade in service.

.And the software bug lied dormant for so many years it seems and correction measures are now under way.


The fact ADA has so far managed without a crash or even severe emergency on LCA tejas itself is a credit to the program.

And the experience in control laws (CLAWS) will be immensely helpful in AURA and AMCA program .

 

[ersakthivel]

Air War at the Top of the World

A report on IAF role during kargil conflict

 

[ersakthivel]

 

[p2prada]

ADA and HAL wud have delivered this ac long long back had it not been for the officers of IAF who on instructions from MOD have changed the specs many times in their effort to kill this project. The Specs for MK2 have now been fixed not bcoz of IAF but bcoz of IN who have now taken a Pivot position on the development of this aircraft.

According to Air Marshal Rajkumar, it was the exact opposite. IAF had initially asked for an aircraft at a lower level as compared to JF-17, it was DRDO which unilaterally promised the moon and upped the specs. IAF had not even asked for a digital FBW, it was an ADA decision.

Specs increase is natural after a certain time threshold is passed. 1980s specs will no longer find place in 2012, especially when ADA unilaterally increased specs after full scale development started. Even SWAF is running around the Swedish parliament claiming Gripen C is obsolete and they want better aircraft.

About the engine, GE released info on two types of F-414s. One was the EDE for enhanced durability and the EPE for enhanced thrust. Both are one and the same and made from the same materials. One maintains the same levels of power as before, 98KN, with enhanced life while the other simply increases basic levels of thrust to 120KN maintaining similar life as the earlier F-414 versions. So, we can say the F-414 we ordered may be similar to the EDE/EPE with thrust that comes in between the two. Of course, I don't know if the INS6 is the same, or a superior version or an inferior version, as the EDE.

While engine is a non-issue for the IAF, it may cause problems for the IN. Even if they do clear out all problems, they are not sure if the paper based predictions will match with the prototypes. That's why the orders for only 8 engines.

Anyway aux air intakes are worthless when it comes to air combat. The ADA did a sloppy job of the air intakes and the aux intakes was only a piece meal measure to reach only some parameters of the actual required specs. Nevertheless it was the IAF who asked for aux intakes, in 2006 or 2007. The aux intakes are mostly for stable flight, not for dog fights. So, no extra power during the most crucial flight profile. But this is limited to only the IAF and IN Mk1s. There may be a 0.5inch increase in diameter for the Mk2's intakes, but it may not be enough for the Navy's requirement of 120KN. I don't know if it is even enough if IAF asks for 100-110KN. The 0.5 inch figure was for a 98KN thrust when it was first revealed. But, I guess there is scope for redesign here since the time table has been stretched to 2020.

Anyway, the LCA Mk1 cannot do more than Mach 1.4 or Mach 1.5 due to the light of these facts, with clean loads. May marginally cross Mach 1.5 for production models. Not sure if it will ever breach supersonic speeds at sea level also. Overall the Mk1 will be far superior to the Indian Navy's Sea Harrier even with these specs, so naturally they will be satisfied. So, trainer versions based on Mk1 will be good for the Navy for obvious reasons.

We may see the fitment of canards on Mk2, but nobody is sure about it because there will be a drastic improvement in power with the new engine. Anyway, the news about canards, aux intakes are all news from 2007, not recent. Aux intakes were fitted on prototypes in 2008. No, it didn't particularly help.

 

[ersakthivel]

According to Air Marshal Rajkumar, it was the exact opposite. IAF had initially asked for an aircraft at a lower level as compared to JF-17, it was DRDO which unilaterally promised the moon and upped the specs. IAF had not even asked for a digital FBW, it was an ADA decision.

Specs increase is natural after a certain time threshold is passed. 1980s specs will no longer find place in 2012, especially when ADA unilaterally increased specs after full scale development started. Even SWAF is running around the Swedish parliament claiming Gripen C is obsolete and they want better aircraft.

About the engine, GE released info on two types of F-414s. One was the EDE for enhanced durability and the EPE for enhanced thrust. Both are one and the same and made from the same materials. One maintains the same levels of power as before, 98KN, with enhanced life while the other simply increases basic levels of thrust to 120KN maintaining similar life as the earlier F-414 versions. So, we can say the F-414 we ordered may be similar to the EDE/EPE with thrust that comes in between the two. Of course, I don't know if the INS6 is the same, or a superior version or an inferior version, as the EDE.

While engine is a non-issue for the IAF, it may cause problems for the IN. Even if they do clear out all problems, they are not sure if the paper based predictions will match with the prototypes. That's why the orders for only 8 engines.

Anyway aux air intakes are worthless when it comes to air combat. The ADA did a sloppy job of the air intakes and the aux intakes was only a piece meal measure to reach only some parameters of the actual required specs. Nevertheless it was the IAF who asked for aux intakes, in 2006 or 2007. The aux intakes are mostly for stable flight, not for dog fights. So, no extra power during the most crucial flight profile. But this is limited to only the IAF and IN Mk1s. There may be a 0.5inch increase in diameter for the Mk2's intakes, but it may not be enough for the Navy's requirement of 120KN. I don't know if it is even enough if IAF asks for 100-110KN. The 0.5 inch figure was for a 98KN thrust when it was first revealed. But, I guess there is scope for redesign here since the time table has been stretched to 2020.

Anyway, the LCA Mk1 cannot do more than Mach 1.4 or Mach 1.5 due to the light of these facts, with clean loads. May marginally cross Mach 1.5 for production models. Not sure if it will ever breach supersonic speeds at sea level also. Overall the Mk1 will be far superior to the Indian Navy's Sea Harrier even with these specs, so naturally they will be satisfied. So, trainer versions based on Mk1 will be good for the Navy for obvious reasons.

We may see the fitment of canards on Mk2, but nobody is sure about it because there will be a drastic improvement in power with the new engine. Anyway, the news about canards, aux intakes are all news from 2007, not recent. Aux intakes were fitted on prototypes in 2008. No, it didn't particularly help.

Anything other than a fully relaxed stability platform with unstable flight profile flown by digital fly by wire would have been obsolete like JF17 right now.So ADA made the right choice after all.

If ada has delivered such a low spec aircraft in the form of mere mig-21 replacement ,it would have been obsolete by now and wont even counter the JF-17.


So there is no design top speed intent behind aux intake ,Remember every piece in engineeering is designed with a purpose in mind.By the same token youare saying aux intake is a waste in JAGS.

Which part of the flight profile it will improve and in which it wont?

Because tejas reached mach 1.6 at just 7 KM height itself as per ADA website,SO it has the potential to reach much higher speeds at service ceiling even in mk-1 design, as it is the norm for all fighters.

IMHO these aux air intakes will help it to reach top speed of mach 1.8 in service ceiling.Because they can be opened and closed when needed.

That must be the design intent behind it. If the engine is powerful enough to give it a top speed noway you can argue that ADA wont be able to design an air intake to supply it with enough air to reach the full thrust.

Tejas has crossed mach 1.6 , one year before you were insisting that it never crossed mach 1.4(now you are saying mach 1.4 or mach 1.5 )

And it did mach 1.1 at sea level without these aux intakes one year before you were insisting that it was subsonic at sea level.
It did this during a dive in flutter test to gain acceleration and then flew in a level flight at this speed.Then how did the engine got air to power the level flight?

And intakes are proposed to be expanded by 5 percent in mk-2 , not 0.5 inch as per your claim.

 

[Sam2012]

Good pics

But should't IAF induct LCA & then work with ADA & HAL constantly upgrading it ?? Isn't the aircraft better than Mig-21, Mig-27 & Jaguar?

When we bought Mig-29B in 80s it was nowhere near fully operational , now see MIG-29SMT ? if IAF can import partially operational aircraft then why not LCA?

Same story with Sukhoi as well first it was Su-30K only after that Su-30MKI came in , why such double standards

All battle proven aircrafts eg: F-16, F-14D, F-15, Mirage have started as basic design aircraft & got clearance from respective airforce then gradually they have been upgarded into the fearful beast which they are now

Agreed HAL is guilty party but still we have give importance to our Indeginous project or else Gorshkov , Scopene etc cost escalation projects will be poor tax payers head

Indian Navy is more willing to go for indeginous platform than the IAF & IA this is my point of view

 

[Sam2012]

Can we made Tejas twin engine......If not then why ?

Our IAF friends are not accepting single engine itself , twin engine they will say we will buy Rafale or Typhoon instead

But LCA twin engine is good concept which can be used as ground attack aircraft replacing Mig-27 & Jaguar , concept similar to F-15 strike eagle

 

[Decklander]

I had stated very clearly that intakes provide insufficient air at low speeds and high AOA regimes. The aux intakes are to improve the airflow only in these regimes as at high speeds the ram effect provides adequate airflow to the engine. Plus the original LCA was fitted with a 85KN engine and the new LCA is fitted with a 89KN engine. SO increased airflow was needed.

 

[sathya]

so AUX intake wont increase the max speed of mach 1.6

where as it ll improve the low speed manoeuvres including dog fight right ?

only F414 engine with more power can increase the the max speed,

ADA said omly 85% of flight envelope opened up so far..
does it include speed too ? like only 85% of speed and we have 15% more to be used?

 

[p2prada]

I had stated very clearly that intakes provide insufficient air at low speeds and high AOA regimes. The aux intakes are to improve the airflow only in these regimes as at high speeds the ram effect provides adequate airflow to the engine. Plus the original LCA was fitted with a 85KN engine and the new LCA is fitted with a 89KN engine. SO increased airflow was needed.

I wasn't really countering your post there with regard to aux intakes. Only adding my 2 cents to it. I apologize if it came out as confrontational.

I was only pointing out the new engine won't be the EPE, at least for the IAF version.

so AUX intake wont increase the max speed of mach 1.6

where as it ll improve the low speed manoeuvres including dog fight right ?

only F414 engine with more power can increase the the max speed,

ADA said omly 85% of flight envelope opened up so far..
does it include speed too ? like only 85% of speed and we have 15% more to be used?

No aux intakes don't help achieve even Mach 1.5 speed. LCA isn't designed for high speed like cold war fighters. Anywhere between mach 1.6 and mach 2 is enough for modern fighters. All that high speed requirement currently does not exist, especially with regards to IAF.

The opening up of the flight profile has nothing to do with achieving top speed. The opening up of the flight profile is directly related to aspects like AoA, turn and roll rates, G limits etc.

The problem with LCA is that it has become heavier without an equivalent increase in thrust. The intake design is its limiting factor and has been discussed before. That's why the top speed is lower than what's required. Anyway, IAF is not upset about the current top speed. They are more interested in AoA, G and turn rates. Reliability is an entirely different issue and industrial production, a whole another issue.

 

[p2prada]

Anything other than a fully relaxed stability platform with unstable flight profile flown by digital fly by wire would have been obsolete like JF17 right now.So ADA made the right choice after all.

If ada has delivered such a low spec aircraft in the form of mere mig-21 replacement ,it would have been obsolete by now and wont even counter the JF-17.

LCAs delay is primarily attributed to the failure of developing a FBW system in time. With the analog system that Dassault was willing to provide back in 1987, we could have put the LCA in service in the early part of last decade and brought in major improvements with the MK2 which would have started induction today, maybe even half a decade ago.

No need to ridicule the JF-17 either. It is a RSS platform. Just because you and farhan don't understand what FBW and the terms quadruplex and duplex mean, that doesn't change the fact that the JF is a RSS platform.

 

[Kunal Biswas]

Tejas flying in formations..