LCA Tejas: News and Discussions

deejay · Post by **deejay** » 30 Jul 2015 18:33

nileshjr wrote:
deejay wrote: I have been watching flying from HAL airport keenly for last 02 months....
deejay saar..one aam abdul puchh..OT here but was being curious so asking. I am seeing some jets flying from HAL strip but can't identify them. Looks like Jet Trainers to my un-trained eyes ( ). Can you tell me which one are they? IJT or AJT?? I thought I saw Jaguar as well a couple of times.

Lots of Jaguars flying, 01 M2K too, occasional Mig 21s, Kirans and many Hawks. Last IJT I saw was more than 02 weeks ago.

member_23694 · Post by **member_23694** » 31 Jul 2015 15:01

http://economictimes.indiatimes.com/new ... 295273.cms

According to Parrikar, the following shortcomings have been reported in LCA Tejas Mk-I:

> Absence of Internal Jammer affecting survivability.

> Aircraft performance shortfalls.

> Maintainability issues.

In a release, the Ministry of Defence said that the shortcomings were primarily due to following reasons:

> Internal jammer technology at that time was based on TWT amplifier which needed about 1000 ltr volume space for integration on aircraft. Hence it could not be accommodated at the time of development of LCA Tejas, Mk-I.

> The maintainability issues were raised by Indian Air Force (IAF) late in 2009, when design and drawings were already frozen for Mk-I. However, many of the safety critical maintenance issues are already addressed in Mk-I.

Karan M · Post by **Karan M** » 31 Jul 2015 15:16

>>> The maintainability issues were raised by Indian Air Force (IAF) late in 2009, when design and drawings were already frozen for Mk-I. However, many of the safety critical maintenance issues are already addressed in Mk-I.

Yet another late "change the design now since we joined the program late" issue from the IAF side. And so it goes.
Maitya, if you are around, another datapoint.

Anyways hopefully the Mk2 will have this covered.

Karan M · Post by **Karan M** » 31 Jul 2015 15:17

>> All the above mentioned shortcomings in LCA Mk-I have been addressed in LCA Mk-II version, the release added.

Read more at:
http://economictimes.indiatimes.com/art ... aign=cppst

shiv · Post by **shiv** » 31 Jul 2015 21:22

Karan M wrote:>> All the above mentioned shortcomings in LCA Mk-I have been addressed in LCA Mk-II version, the release added.

Read more at:
http://economictimes.indiatimes.com/art ... aign=cppst

Could someone please educate me about the following quote

Internal jammer technology at that time was based on TWT amplifier which needed about 1000 ltr volume space for integration on aircraft. Hence it could not be accommodated at the time of development of LCA Tejas, Mk-I.

What is a TWT amplifier?

Why would it need 1000 liters volume?

What is "current state of the art" in this area?

Karan M · Post by **Karan M** » 31 Jul 2015 21:35

TWT amplifier is a Travelling Wave Tube, its basically a bulky piece of equipment to amplify the RF from the signal generator so as to send it out through the antennae. Basically your RWR receives radar signals, you send it to a radar signal processor, it then decides what to jam and how, that signal then goes to the TWT and then back out for transmission, with some buffer built in for losses. Current state of art are MPMs (Microwave Power Modules) and AESA wherein you combine the entire Rx/Tx part in a compact package & hence make it modular.
What they mean by the 1000 Ltrs Volume part is that the entire jammer tech they had available locally took up that much space, equivalent to a 1000 Ltr tank when placed internally.
This is the jammer tech (IMO) they are talking about.
http://3.bp.blogspot.com/-ezhzTDjWMTA/U ... -27UPG.jpg
Now, the new program is to build a compact system which can be deployed across multiple platforms. The MPM one I think is for the LCA (going by memory) and AESA variant for MiG-29.
http://1.bp.blogspot.com/-VEkoVw7dNQI/U ... as+Mk1.JPG

shiv · Post by **shiv** » 01 Aug 2015 05:52

Karan M wrote:TWT amplifier is a Travelling Wave Tube, its basically a bulky piece of equipment to amplify the RF from the signal generator so as to send it out through the antennae. Basically your RWR receives radar signals, you send it to a radar signal processor, it then decides what to jam and how, that signal then goes to the TWT and then back out for transmission, with some buffer built in for losses. Current state of art are MPMs (Microwave Power Modules) and AESA wherein you combine the entire Rx/Tx part in a compact package & hence make it modular.
What they mean by the 1000 Ltrs Volume part is that the entire jammer tech they had available locally took up that much space, equivalent to a 1000 Ltr tank when placed internally.
This is the jammer tech (IMO) they are talking about.
http://3.bp.blogspot.com/-ezhzTDjWMTA/U ... -27UPG.jpg
Now, the new program is to build a compact system which can be deployed across multiple platforms. The MPM one I think is for the LCA (going by memory) and AESA variant for MiG-29.
http://1.bp.blogspot.com/-VEkoVw7dNQI/U ... as+Mk1.JPG

Thanks. My aunt Kokila tells me that Tusker pods have been on MiG 27s and Jags. Do you think (just speculation) that there could be a theoretical situation of LCA Mk 1 carrying a Litening and Tusker, 2 X 250 kg LGBs and two drop tanks?

One Tusker pod (it seems to me) should be able protect a group of planes flying together in formation? Do you think that is right?

Shreeman · Post by **Shreeman** » 01 Aug 2015 12:09

^^ Shiv,

For an intercepter in the Mig 21 class, that goes up to meet an incoming threat the SPJ nonsense, especially radar protection, is of very limited role. Even the R21 class of projectiles has an IR seeker. Now for a true multi role intruder, you could argue strongly for an internal SPJ. This craft doesnt want to intrude on the multi role turf in this form. Never was meant to.

The rest of the whining is sounding like they have run out of issues to complain about.

Karan M · Post by **Karan M** » 01 Aug 2015 16:06

shiv wrote:
Karan M wrote:TWT amplifier is a Travelling Wave Tube, its basically a bulky piece of equipment to amplify the RF from the signal generator so as to send it out through the antennae. Basically your RWR receives radar signals, you send it to a radar signal processor, it then decides what to jam and how, that signal then goes to the TWT and then back out for transmission, with some buffer built in for losses. Current state of art are MPMs (Microwave Power Modules) and AESA wherein you combine the entire Rx/Tx part in a compact package & hence make it modular.
What they mean by the 1000 Ltrs Volume part is that the entire jammer tech they had available locally took up that much space, equivalent to a 1000 Ltr tank when placed internally.
This is the jammer tech (IMO) they are talking about.
http://3.bp.blogspot.com/-ezhzTDjWMTA/U ... -27UPG.jpg
Now, the new program is to build a compact system which can be deployed across multiple platforms. The MPM one I think is for the LCA (going by memory) and AESA variant for MiG-29.
http://1.bp.blogspot.com/-VEkoVw7dNQI/U ... as+Mk1.JPG
Thanks. My aunt Kokila tells me that Tusker pods have been on MiG 27s and Jags. Do you think (just speculation) that there could be a theoretical situation of LCA Mk 1 carrying a Litening and Tusker, 2 X 250 kg LGBs and two drop tanks?

One Tusker pod (it seems to me) should be able protect a group of planes flying together in formation? Do you think that is right?

Shivji, whether it has been tested in the role is a key point.

The average jammer has to protect the aircraft in a 360 degree bubble or at least in those quadrants which are deemed high threat. The jammers are then broken into two categories, escort and self protection. These are either for a variety of Ground Based + A2A threats (escort) or SPJs (mostly A2A).
Ideally, every aircraft in the formation should have a SPJ and they have at least one or two escort jammers to protect the entire formation. Per my understanding, the Tusker, despite its size, is a SPJ (6-18 GHz, it covers the X Band - fighter radars, and Ku band for missile seekers ). Its not an escort jammer which have more antenna and higher power (simplistically speaking) to do greater work. The Tusker was apparently tested against all available IAF radars at the time and fared well.

However, it was not deployed on the LCA Mk1 or integrated or tested. Theoretically it could be, provided a pylon was made compatible (its 250 kg weight makes it lightweight). However, in your payload combo above, the IAF would also want A2A missiles for self defence, at least Python-5s.

Theoretically the answer is yes, if they can qualify a pylon and manage the EMI/EMC tests (you don't want the jammer to "blank" your RWR or radar or mess with your other electronics. Plus provide coverage).

So we are speaking of a 2*Python-5 Missiles, followed by 2*500 LGBs (IIRC all our LGBs seem to be 450kg+ class), then 2*fuel tanks, a Litening on the special 7th pylon, which leaves a central pylon for a Tusker style pod (if tested and qualified).

Now if there is no Tusker, can the Tejas still manage with escort jammers, especially for strike.
A clue may be found here:http://www.slideshare.net/agcool/eye-on ... rch-2014-s
In Aug 2013, the IAF did put out a RFI for escort jammers. We have been interested in these for a while now but given how sensitive the topic is, the IAF doesn't publicize its choices and changes & even how its rectified issues.

If not the Tusker the other SPJ to deploy would be (IMO) the Israeli EL/L-8222. We should have a good stock of these available as the MiG-27 Upgs and earlier Bisons retire, plus the ones on the Su-30s which have moved onto the SAP-518 series from Russia (Israeli jammers didn't work out on the Su-30 airframe).

You can see a Bison with the Israeli SPJ here:

A SPJ on a small airframe like the LCA can be a powerful combination. In the much ballyhooed Red Flag debrief from a USAF Colonel (who made up stuff about the Su-30 performance but unwittingly gave away details about the F-22 and earlier IAF-USAF exercises), he said the US F-15s had a tough time against the Bisons with Israeli jammers.

Austin · Post by **Austin** » 01 Aug 2015 18:38

^^ I am not sure if the Good Colonel was speaking the truth because chances are like MKI radar was used in training mode the jammer could have been used in similar mode.

Karan M · Post by **Karan M** » 01 Aug 2015 18:46

He was apparently not supposed to give away details. Which is why I said unwittingly. If the jammer was used in training mode and still performed like the MKI radar, it speaks well of it. The EL/L-822 SPJ is btw used by IDF F-15s. It would hence be very useful for a small airframe.

shiv · Post by **shiv** » 01 Aug 2015 19:06

Karan M - that was a great, informative post. Thanks

ramana · Post by **ramana** » 01 Aug 2015 21:53

Most engagements are to kill and not be killed. SPJ helps against the radar guided AAM threat. So its a big deal. Survivability aspect.

Austin · Post by **Austin** » 01 Aug 2015 22:44

Even WVR IR missile need to get range to target something a radar gets for it , WVR are not necessarily very close proximity knife fight where Laser Range would just be enough and ranging is a crtical aspect of FC to the missile. In any case an SPJ would be a useful chap every aircraft pilot would like to have.

SaiK · Post by **SaiK** » 02 Aug 2015 00:14

why pods? it should be built in by default

ramana · Post by **ramana** » 02 Aug 2015 01:23

SaiK wrote:why pods? it should be built in by default

Precisely. Hence Mk2 will have a distributed SPG. See picture posted by KaranM

Nick_S · Post by **Nick_S** » 02 Aug 2015 05:30

I wonder why IAF is not requesting for a Towed Radar Decoy like on Eurobug (TRD)

or Superbug (https://en.wikipedia.org/wiki/ALE-50_Towed_Decoy_System)

As per wiki, might be a life saving measure -

The ALE-50 system consists of a launcher and launch controller installed on the aircraft (usually on a wing pylon), and one or more expendable towed decoys. Each decoy is delivered in a sealed canister and has a ten-year shelf life.

When deployed, the decoy is towed behind the host aircraft, protecting the aircraft and its crew against RF-guided missiles by luring the missile toward the decoy and away from the intended target. In both flight tests and actual combat, the ALE-50 has successfully countered numerous live firings of both surface-to-air and air-to-air missiles. U.S. military pilots have nicknamed the decoy "Little Buddy".

The ALE-50 expendable decoys’ estimated value is $22,000 each.

The ALE-50 towed decoy has provided combat-proven aircraft protection against RF missile threats in Kosovo, Afghanistan, and Iraq. Featuring low acquisition and life-cycle cost, the system adaptability enables installation and operation on virtually any airborne platform.

Shreeman · Post by **Shreeman** » 02 Aug 2015 05:52

Ramana,

Not questioning the importance of an SPJ. Like decoys, a hundred other devices could be crammed in, if scope is to forever expand.

Re. ranging, that is something a J of some sort may or may not prevent. And being more or less ignorant of the art now, I also question the utility of radar ranging in OLS type IRST/LR equipped craft. Technology gets better every day. LR of ground targets has been the norm forever. What is considered to be an average mile distance for your typical OLS-30 kind IRST/LR sensorto range accurately? Wiki notes numbers of 50 miles detection and 60% of that, 30 miles engagement for some example. Thats not a knife fight.

srai · Post by **srai** » 02 Aug 2015 06:09

SaiK wrote:why pods? it should be built in by default

Back when LCA was in development SPJs were the size of 1000ltr tanks. But now with next generation SPJs these are compact enough to be fitted in the LCA, which is what the Mk.2 will have. Mk.1, for the time being, will need to rely on a SPJ on pod. There is 200kg of ballast in the Mk.1 airframe and this dead space could be used for an internal SPJ at MLU.

fanne · Post by **fanne** » 02 Aug 2015 06:50

SPJ is a good idea, but why internal SPJ? LCA does not have the volume. This requirement may never be met in MK1. Is this a poison pill to kill LCA?

shiv · Post by **shiv** » 02 Aug 2015 06:58

I am currently reading PC Lal's autobiography "My years with the IAF". He like many others points out how the forces innovate at wartime - using stuff that they have for some other purpose to fit into a different role. It was in this light that I asked that if LCA Mk 1 did not have the internal space for a Tusker SPJ (Self Protection Jammer) - I was speculating if it (Tusker, that is, not towed or internal) could be useful on a pylon.

member_28482 · Post by **member_28482** » 03 Aug 2015 14:08

The Light Combat Aircraft Tejas to demonstrate fire power ahead of FOC
https://www.ibcworldnews.com/2015/07/01 ... ad-of-foc/
July-Already pased, Any Report on this..

srai · Post by **srai** » 03 Aug 2015 15:44

^^^
Have refueling probe and nose cone radome arrived from Cobham?

...
Refueling probe, nose cone radome awaited ::
To complete the FOC points, the air-to-air refueling probe from Cobham hasn’t arrived yet. The nose cone quartz radome too is being awaited.

There are already some rumours floating around in the corridors of HAL and ADA over the delay in accessing these pending foreign systems.

A Defence Research and Development Organisation (DRDO) official says that they are hopeful of thrashing the issue.

“Definitely there are concerns. But, we are hoping to get clarity by July. Hopefully, we should have access to all hardware within a month. We don’t see any more technology challenges after the integration of these pending items,” says the senior DRDO official.
...

brar_w · Post by **brar_w** » 03 Aug 2015 19:15

Since there was a discussion on the analog legacy EW Jammers here is a neat video explaining how they work tactically ...

Shreeman · Post by **Shreeman** » 03 Aug 2015 19:29

It will take another year to make the radome, signal loss issues, materials not ready, interference in the proprietary band used by ijraelis which cobham had never encountered before. The probe is held up as part of the same delivery. Since it will mean 2017 FOC, the whole thing might well be merged into Mk2. In the meantime, a few, shall we say, swedish apples, for good health.

ps - /s. before someone decides to make a DDM artikile out of it.

Karan M · Post by **Karan M** » 03 Aug 2015 22:38

Nick_S, there is/was a plan to make a TRD by DARE along with a private partner. Might be worth checking as to what's going on. Its "All quiet" on the EW front. I guess DARE is busy making sure the Su-30 MKIs new RWRs work well, and the LCA, MiG-29, AEW&C ESM/EW suites work out.
Along with FCRs, the above are the key area where we still need to break the hurdle and launch mass production programs as we have managed in missiles and other systems.

SaiK · Post by **SaiK** » 04 Aug 2015 18:03

http://www.livefistdefence.com/2015/08/ ... e-not.html

The way these people quote and say it appears it was for Mk1.

GoI and MoD must not mix Mk1 and Mk2 in one press release

Kakkaji · Post by **Kakkaji** » 04 Aug 2015 21:49

India may avail consultancy from Tejas Mk-II Euro bidders

PTI story, so hopefully not total hogwash.

SaiK · Post by **SaiK** » 04 Aug 2015 22:05

so much of struggle so early in the life-cycle for mk-2!

btw, i am not pessimistic

srai · Post by **srai** » 05 Aug 2015 03:29

Kakkaji wrote:India may avail consultancy from Tejas Mk-II Euro bidders
...

...
"Technologies, systems engineering and experience gained during development of LCA Tejas Mk-II would benefit the development of Fifth Generation Aircraft indigenously," Parrikar said.

He says this about Mk.2 as an experience required for 5th-Gen aircraft, but then somehow "fails" to see the same on the Arjun MBT front and its implication for FMBT/FRCV.

Army's RFI for tanks not in conflict with DRDO project: Parrikar

wig · Post by **wig** » 05 Aug 2015 10:27

This information was given by Defence Minister Shri Manohar Parrikar in a written reply to Shri Vijay Jawaharlal Darda in Rajya Sabha on 04 August. The LCA Mk 2 will be operation towards the start of 2023.

http://pib.nic.in/newsite/erelease.aspx?relid=0

The project for design and development of Light combat Aircraft (LCA), Tejas Mk-II was sanctioned in November 2009 at a cost of Rs.2431.55 Crore with Probable Date of Completion (PDC) of December 2018. However, because of delay in finalisation of Engine Contract, the project could start only in December 2013. As a result, maiden flight of first Prototype and Operational Clearance are likely to be completed by December 2019 and December 2022, respectively. There after induction.

Aeronautical Development Agency (ADA), Bengaluru is the Nodal Agency for design and development of Light Combat Aircraft (LCA) Tejas Mk-II. ADA has not entered into any collaboration with European Aircraft Manufacturers who had participated in the Medium Multi Role Combat Aircraft (MMRCA) tenders for development of Tejas Mk-II. However, ADA may like to avail consultancy from some of them.

Light Combat Aircraft (LCA) Tejas Mk-II would be an improved version of LCA Mk-I. Some of the new systems / technologies, like Active Electrically Scanned Array (AESA) Radar, Unified Electronic Warfare (EW) Suite, On Board Oxygen Generation System (OBOGS), Upgraded Avionics, etc. are to be included in LCA Tejas Mk-II to make the aircraft more contemporary. Technologies, systems engineering and experience gained during development of LCA Tejas Mk-II would benefit the development of Fifth Generation Aircraft indigenously.

.

Aditya_V · Post by **Aditya_V** » 05 Aug 2015 10:33

srai wrote:
Army's RFI for tanks not in conflict with DRDO project: Parrikar

Might be being a bit overgenerous here. But this RFI might be to find out what are emerging Technologies/ Designs which other nations are working on and to part with information not available in the public domain.

Dileep · Post by **Dileep** » 06 Aug 2015 08:07

Posting here for better eyeballs.

We have an audit from CEMILAC scheduled next week. Audit is for recognition as a design house. Is there anyone who could provide any information on what to expect?

Thanks in advance. You can contact me dileepks at jeemeyil daat kaam

Singha · Post by **Singha** » 06 Aug 2015 20:18

Dileep there is some data here https://www.google.co.in/url?url=http:/ ... 0g&cad=rja

instead of waiting until the last minute i think cemilac itself would have shared the requirements doc and test points if you asked them earlier?

Dileep · Post by **Dileep** » 08 Aug 2015 06:09

^^It shows you haven't dealt with the guvermand entities yet

. It also shows that you don't think too high of myself (trying to help with a google search link and chiding for not acting earlier, hain ji?)

Seriously, we had been working with them for several months now. They will not tell you what they look for or what they would do. They shared a very plain, generic document after a lot of begging by our QMS guy, which gives no useful information on what they expect. We are pretty good covered on the established standards and practices. The purpose of asking here was to know if there is someone who would share some firsthand experience.

Found out that either no one is here, or the ones don't want to help.

SaiK · Post by **SaiK** » 08 Aug 2015 08:12

Dileep.. you should have been given what product/services your company is providing against some min requirements. now, let us say, you have your own brochure that talks about say the radar computer you are developing.. the inspection can go to anything they wish to qualify from quality of the product to specifications you have listed with tolerances and performances.. it is a big process.. it can't be one stop by filmie types. you know more than me..

if you follow CMMI, then you have pretty much documented quality product ready. /eg

example: software/ sometimes TP V&V guys do fagan inspections to few KBs, especially dealing with embedded and process control systems... they have their own measures and metrics collections based on previous inspections.

Dileep wrote:^^ or the ones don't want to help.

you don't want your fellow rakshaks lose their job.. don't you?

In the above example, I would expect them your company to provide the radar computer, with details specs.. instructions, etc. they would do their own testing based on their requirements.. may be they will lab test it, put on a radar to process and see results. they might give you one liner that it failed to meet their needs. if they tell you on specifics you failed, then there may be some gov clauses for that... to even debarring to sell again
--
btw, where is our LCA master Mr Indranil Roy? perhaps he might have more clues for you.

ps: if they are auditing.. they might ask you to show the QC process, or even code review of software , even perhaps know the defects you have and if you have MC/DC coverage etc.

Hitesh · Post by **Hitesh** » 08 Aug 2015 08:39

If the IAF is unhappy with the current configuration of the LCA, why can't we start with a new clean design that would correct all the shortcomings? We have mastered the necessary avionics and parts that goes inside the aircraft. It would take us a shorter time to come up with a new clean design that can work with the Kaveri engine or the GE engine and provide the necessary thrust and high energy envelope.

SaiK · Post by **SaiK** » 08 Aug 2015 08:46

you have mastered only what you have got. you have not mastered what they ask for.. so you are screwed back like LCA Mk1 happened.. this is the freaking reason why people say, freeze that darn requirement first.. don't change.. or don't begin we have deterministically proven that is exactly what IAF wants. IAF is not product developer, hence it was a big mistake to sit with them to develop to requirements [foolish to think the user will never change reqs]. IAF should have been pure stake holder and drafting future requirements rather asking for changed requirements to their current strength (Migs then).. so it is a requirement screw up in the first place.

starting from scratch is like redoing everything again.. to an extent they are doing it in Mk2... and parrikar says, this time process will be fast... there are changes everywhere to be done from control laws to wing dynamics.

srai · Post by **srai** » 08 Aug 2015 09:51

Hitesh,

It's not a small classroom science project that can be restarted with new design. If you want to do that, it will take you 20 years to get it to FOC and production. Flight testing and qualifications are no trivial task along with coming up with "optimal" aircraft design and integration of thousands of parts. These things take time. And as SaiK pointed out, the user will likely move the goalpost every so often in its desire to get the latest and greatest.

Look, even Mk.2 with some refinements to the Mk.1 will take 10+ years to get it to production. Any completely new design would take even longer. This is world-wide I'm speaking of not just India.

Hitesh · Post by **Hitesh** » 08 Aug 2015 11:33

From what I am understanding, IAF's biggest complaint about the LCA is the lack of sufficient airflow because the diameter of the intakes are too small and that leads to less than optimal thrust in which the engine cannot fulfill its maximum potential because of insufficient airflow.

You don't need to change the wingshape but you do need to increase the size of the intakes to generate more airflow. You can keep the cockpit and the nose and the wings (to a lesser extent) as they are. Just increase the length of the fuselage and the size of the intake and adjust the wings' size accordingly.

Of course I have absolutely zero knowledge in aerospace design or engineering so I may be talking out of my ass. But do please educate me.