LCA: News & Discussions - October 2016

[Cybaru]

Is it necessary to waste a post sniping at others? There was nothing else in the post that you have any opinion to contribute or find to be any use in triggering any thought? There is something so pure and stuck-up about this forum that makes it superior to those other "forums"? (the word is fora, if one really wishes to be correct and classy..)
Yes, I can post in any type of English at any level of stuck-up-ness, what-what I say, but see no need to do so. In fact, I post here for relaxation, not as a primary place of technical, strategic or military dissemination. Or to posture.

Thanks for understanding. Appreciate you reading and reponding. I like reading your post, but all the translating takes too much effort. No more from me.

[Zynda]

JayS, good post as usual. A couple of minor corrections.

Almost since 1920s, with the application of monocoque design approach, aircraft skins are always loaded structural members. It shifted to semi-monocoque design soon where skin has underlying reinforcements in the form of stringers and frames. In modern design for civil jet liners for example, upper and lower wing skin form the top and bottom part of the wing torsion box, the other two parts being front and rear spar. Likewise the fuselage skin is loaded completely.

Skin being thin metal/composite panels they don't take shear.

Actually membrane elements can resist in-plane shear...what you are referring above is transverse shear which membrane elements are not effective. Further, aircraft skin elements do not behave as pure membrane or as pure plate elements. Their actual behavior, just like many things in real life, is some where between the two.

They only take up in-plane forces i.e. tension and compression. While its easy to load them under tension (think of stretched cloth), for compression they have reinforcing structural components below them (not the airframe structure but longerons circular frames, stingers etc >> semi-monocoque design)

Up to limit load, usually skin elements are effective in both tension and compression. Beyond LL, skins lose their effectiveness in compression, however skins in tension continue to be effective. As you have mentioned, longerons & stringers will continue to bear additional compressive load in fuselage while in Wing, the job is taken over by the spar & stringers.

In actual practice, it depends on what you are assumptions are during design phase about skin effectiveness (hence testing is necessary to validate your assumptions/mathematical models ).

However now the parts are being manufactured in Pvt industry.

Saar, which Pvt. entity in India is fabricating composite panels?

The above post may be OT for LCA in general....

[JayS]

Actually membrane elements can resist in-plane shear...what you are referring above is transverse shear which membrane elements are not effective. Further, aircraft skin elements do not behave as pure membrane or as pure plate elements. Their actual behavior, just like many things in real life, is some where between the two.

Didn't want to being in all the details unnecessarily, plate theory and all. I assumed Marten was referring to transverse shear. So only mentioned as such. Easier to imagine a plate in tension/compression than it under in-plane shear.

Up to limit load, usually skin elements are effective in both tension and compression. Beyond LL, skins lose their effectiveness in compression, however skins in tension continue to be effective. As you have mentioned, longerons & stringers will continue to bear additional compressive load in fuselage while in Wing, the job is taken over by the spar & stringers.

In actual practice, it depends on what you are assumptions are during design phase about skin effectiveness (hence testing is necessary to validate your assumptions/mathematical models ).

Yes. My context was only under designed load, normal operation. Beyond LL is a failed condition.

Saar, which Pvt. entity in India is fabricating composite panels?

The above post may be OT for LCA in general....

TASL (or TAML, I get confused between the two) makes a lot of parts for LCA. They are our suppliers. Recently a few colleagues went to see mfg facility, but they didn't allow in LCA section.

You might like this very nice PPT on NAL's Composite capabilities, really impressive.
http://www.icas.org/media/pdf/Workshops ... padhya.pdf

HAL's own composite division manufactures lot of other composite parts.

[tsarkar]

Uttam has a packaged cooling system that fits into the space. It is designed for the nose of LCA. Actually, the cooling package was pointed out at the unit displayed at AI17. It was the actual flight ready unit I am told.

What is the amplification of "flight ready"?

Is it -

A. Hardware that fits in the designated space within the power & cooling capabilities available, and has undergone some degree of shock & vibration testing, that the plane can fly with?

Or

B. A radar prototype with A2A & A2G modes having undergone some degree of testing on the ground and air on Do-228/Hs748 hack?

[JayS]

Uttam has a packaged cooling system that fits into the space. It is designed for the nose of LCA. Actually, the cooling package was pointed out at the unit displayed at AI17. It was the actual flight ready unit I am told.

What is the amplification of "flight ready"?

Is it -

A. Hardware that fits in the designated space within the power & cooling capabilities available, and has undergone some degree of shock & vibration testing, that the plane can fly with?

Or

B. A radar prototype with A2A & A2G modes having undergone some degree of testing on the ground and air on Do-228/Hs748 hack?

Not sure about A completely, vibration part especially. Yes they have designed it keeping in mind the existing LCA config so it should be direct fit for all the interfaces. I asked about the cooling requirement as well. LDRE folks told no mods require as such. Also not sure if they tested current version that is waiting to go on LCA on Do-228 or HS748, but its roof-top tested for sure. What I was told during AI17, they have already gone through one full design iteration with a smaller AESA system where they test flew it on Helicopter. So they are quite confident that they can debug Uttam on LCA in 1-2yrs, because as per the LDRE folks the one major unknown area for them is high speed testing. Having a dedicated test platform would have really helped, I suppose. I was talking to a young lady who was involved in the SW for quite a while and she seemed very confident on the algorithms and overall SW. Take it FWIW.

[Zynda]

Beyond LL is a failed condition.

Not entirely true saar but as you have mentioned, its TMI/OT for this thread

[Dileep]

>> We have not really seen Serial production quality so far from up-close

I did (SP3). It is great. Not sure if it is made by the subcons or NAL. I also saw later serials in the jig (not up close). Also, the LSPs are actually very good in fit and finish.

VEM is another supplier for composites.

Uttam "flight ready" simply means CEMILAC have cleared it to be mounted on the LCA. Not sure what level the software will be. I am told that it has worked well tracking targets of opportunity on the 'rooftop' (which BTW is not a rooftop)

[JayS]

>> We have not really seen Serial production quality so far from up-close

I did (SP3). It is great. Not sure if it is made by the subcons or NAL. I also saw later serials in the jig (not up close). Also, the LSPs are actually very good in fit and finish.

Jingo khush hua..

[suryag]

Dileep sir any idea on SP5 first flight ?

BTW on the software part am pretty sure they have channel propagation models that simulate pathloss and associated receiver characteristics for different altitude, speed combos and would have tested the signal processing algos using the same. They would have obtained a lot of this data from the hybrid on MK1, fingers crossed now hoping for the best!! am pretty sure they will miss catching some UAV during testing and that is when we have to see how all the stakeholders take it forward to fruition

[tsarkar]

Thanks, Jay & Dileep, for the information.

Indeed it would not be a rooftop otherwise nearby resident's balls would be popping like popcorn in a microwave - that we all know was invented while testing radar magnetrons.

While the hardware installation is indeed good news, I would be a bit cautious regarding the timelines - the AEW&C testing did take time and basically volume search & track and doesnt have dogfight modes like lookup/lookdown/high-g modes with associated clutter/jamming rejection as well as missile guidance modes for LOBL/LOAL.

I'm not sure how many readers have read Phanishwar Nath Renu's Panchlight to get the gist of hardware vs software. That story was written much before software became prevalent.

Is there a datalink capability on Uttam? Please answer only if its not confidential.

[JayS]

While the hardware installation is indeed good news, I would be a bit cautious regarding the timelines - the AEW&C testing did take time and basically volume search & track and doesnt have dogfight modes like lookup/lookdown/high-g modes with associated clutter/jamming rejection as well as missile guidance modes for LOBL/LOAL.
.

Yeap. So I said take it FWIW. But definitely the work done on various things elsewhere will be feeding in to expedite the process.

Flight tests to start soon, FB admin tells. Don't ask me how soon exactly though. But seems like things are moving in right direction with good speed.

[tsarkar]

Yes, I too hope for the best for both Uttam & LCA. Personally I consider the LCA Navy having the best curves visually among all contemporary fighters.

And a compact land and sea fighter with full capabilities will be a game changer in war.

[Gyan]

1. Mk1s will keep coming with the 2032.
2. As I have told this earlier, the fuel probe is not a big problem. They will not delay FOC with regards to that. IAF only wants the envelop cleared with it before FOC.
3. Gun firing will happen shortly
4. The confidence in Uttam stems from the success of AAAU. I am being told the latter works beautifully. They are modifying LSP2 to carry on the tests. Another factor is the Israelis played up with ADA regarding the BVR testing. ADA wanted some modifications and they were not responding quickly enough and/or favourably enough
5. This is absolutely great news if the decision has been made and going by the number of tenders going out regarding Uttam, I think the rubber has hit the road finally
6. However, it worries me too. This gives the feeling of "we have time". LCA production should be brought up to speed of 16-25 aircraft per year ASAP, and the single engined imported fighter shelved. Mk1 and Mk1A program numbers should be adjusted accordingly.
7. Mk2 program should not be shelved. It will be the proof that we have really gone through at least one cycle of design-build-refine cycle. Let HAL run with Mk1A and ADA with Mk2. Make sure they interact.
8. UB sir, composite parts cannot be hammered, but they can be (and are) trimmed.

The huge delay in integration of Israeli missile with Israeli Avionics & Radar does seem odd.

[ramana]

Which one Gyan?

There is no limitation on the text you can post!

El-2032 and Derby are already integrated. Test firing with live round already completed.

[Gyan]

They are integrated only now. IIRC it took almost 10 years to integrate R73 and Derby to LCA radar.

[Manish_Sharma]

http://wap.business-standard.com/articl ... 231_1.html

Anonymous letter threatens vital Tejas 1A project
By Ajai Shukla | New Delhi | 26 Jul 2017 00:59 am

Not for the first time, an anonymous letter to the ministry of defence (MoD) threatens to delay, if not derail, a vital defence programme: in this case, the Rs 20,000 crore project to develop and build 83 Tejas Mark 1A light combat aircraft, which the MoD sanctioned in November.

On Tuesday, MoD officials, led by Additional Secretary Surina Rajan, met to discuss an unsigned petition the MoD had received against the decision to import a radar for the Tejas Mark 1A fighter. This alleged that national resources were being frittered away in importing an airborne active electronically scanned array (AESA) radar, even though the Defence R&D Organisation (DRDO) had developed indigenous AESA radar.

The anonymous complaint follows a DRDO letter, dated January 5, informing the MoD that it was “working on development of AESA radar” that fully complied with the Tejas Mark 1A requirements. The DRDO requested that it also be given the tender that HAL had issued to global manufacturers of AESA radars.

The letter, which Business Standard has reviewed, makes it clear that the DRDO AESA radar is still far from ready. It notes that two Tejas prototypes are being allotted for “installation and flight evaluation” of its AESA radar. This essential testing process is typically an extended one.

The MoD’s cognizance of the anonymous complaint is already delaying the fast-track development of the Tejas Mark 1A by Hindustan Aeronautics Ltd (HAL); and, thereby, the entry of four Tejas Mark 1A squadrons into the Indian Air Force (IAF) fleet.

As Business Standard first reported (August 13, 2015 “With Tejas Mark II years away, HAL asks air force to buy Tejas Mark 1A”), the Tejas Mark 1A was conceived as an upgraded Tejas Mark 1, with four specific improvements to meet the IAF’s requirements as an operationally capable fighter.

Four key stakeholders – MoD, IAF, HAL and DRDO – agreed together that HAL would enjoy a free hand, including resorting to global purchases, in expeditiously making those four improvements to the Tejas Mark 1. After demonstrating the upgraded fighter to the IAF’s satisfaction by 2018-19, HAL would quickly build 83 fighters (four squadrons) of Tejas Mark 1A.

Of the four upgrades, the most operationally crucial involved equipping the Tejas with AESA radar, in place of the Tejas’ manually scanned Israeli Elta EL/M 2032 radar; and a “self-protection jammer” (SPJ) carried in an external pod under the Tejas’ wing.

Two other upgrades – improving the “maintainability” of the fighter, and fitting it with external refuelling capability are already well in hand.

AESA radar enjoys battle-winning advantages over traditional “manually steered” radar. In the latter, the antenna moves manually to let its radar beam scan the sky for enemy targets. In AESA radar, the beam moves electronically, switching rapidly between many different objects, in effect scanning multiple targets simultaneously. Thus, the “multi-tasking” AESA radar can simultaneously track different enemy aircraft, guide missiles to those, and even radiate electro-magnetic pulses to jam enemy radios and radars. The IAF has concluded that AESA radar would add enormously to the Tejas’ combat capability.

With the DRDO still struggling to miniaturise the AESA enough to fit it in the Tejas fighter’s nose cone, HAL issued a global tender for AESA radars to vendors that included Raytheon (USA), Thales (France), Saab (Sweden) and Israel Aerospace Industries. HAL is currently evaluating the bids that were submitted.

“We must place our order within a couple of months. If we start exploring the DRDO route, we can never meet the deadline of 2018-19”, says a senior HAL executive, speaking off the record.

For now, however, it remains unclear whether the MoD will ignore the anonymous letter, or whether yet another lengthy investigation will ensue.

Disruption of the Tejas Mark 1A time line would also result in the HAL production facility lying unemployed after 2019, when the current order of 20 Tejas Mark 1 fighters would have been delivered.

HAL, which will produce eight Tejas fighters this year, is also implementing a Rs 1,231 crore project to upgrade its production line capacity to 16 Tejas fighters per year. At that production rate, it would complete delivery of 83 Tejas Mark 1A fighters by 2023-24.

[ramana]

Anonymous letter and MoD is ready to derail?
Why not buy 1/2 the order from Israel with option for other half.
Meantime if Uttam shows up don't exercise the option. If Uttam fails the go ahead..
Holding plane for the radar decision is moronic.

[Karan M]

The tone and tenor of the report clearly indicates Shooklaw is batting for an import. Prima facie, there is nothing wrong in DRDO asking for the tender to be open to Uttam too. Wonder why he is conflating that with the anon letter. Next, the claim flight trials will be an extended challenge. Yes, but why wouldnt they be for the Israeli solution whose hardware has to be redesigned for the LCA or the Swedish one, which doesnt even exist!!
HALs import and call it done deal approach is also not optimal. All their "own" programs are a menagerie of imports which rarely if ever involve significant HAL contribution. By all means import when necessary, but progress Uttam in parallel on another two LCAs what is the harm in that? Either split the order or make the call a year from now based on progress.

[ramana]

Better use option for second order. Use business sense.

[ArjunPandit]

raytheon se advance payment aa gai hai shukla saab ko

[alexis]

let us not be hasty in our criticisms. Shukla has been reasonably supportive of Tejas.

[nash]

As per Minister of state for Defence Subhash Bhamre statement in Parliament, FOC of LCA delayed to June 2018, may be FOC will be with MkIA configuration.

[tsarkar]

They are integrated only now. IIRC it took almost 10 years to integrate R73 and Derby to LCA radar.

R-73E was fired 25 October 2007. Derby was delayed because of radome attenuation issues. How will one use BVR missile if radar signal not transmitting/received properly?

http://wap.business-standard.com/article-amp/current-affairs/anonymous-letter-threatens-vital-tejas-1a-project-117072501231_1.html

One good step Manohar Parrikar took was not entertaining anonymous letters/emails/news report or similar BS. Sadly, looks like MoD has relapsed into their old habits.

My take - Uttam will take time - and its criminal to delay Mk1A further.

Best approach is divide 80 odd Mk1A in 5 blocks of 16 each manufactured in a Financial Year. Block 2020, Block 2021, Block 2022, Block 2022, Block 2024. Let the radar decision be taken 1.5 years before each block to enable manufacturer build and ship the radar to HAL assembly line. If Uttam is ready 1.5 years before each block, then let it fit the Mk1A.

Best Practice for foreign radar - shortlist and qualify two - and invite price bids for each block 1.5 years before. That will protect against steep price escalation done by vendors after initial batch.

IN solved the problem quite easily regarding DRDO AIP. They allocated last two Scorpenes. However, when AIP program was delayed, they took a decision NOT to delay the Scorpene and proceeded with build minus AIP. Now AIP is proposed for Project 75I.

Same template can be followed for Uttam.

[sum]

As per Minister of state for Defence Subhash Bhamre statement in Parliament, FOC of LCA delayed to June 2018, may be FOC will be with MkIA configuration.

As feared and predicted....
So,a good data point to ensure the FB LCA admin shouldnt be taken as a gospel since he had repeadtly mentioned that FOC was on track and there were no hitches even very recently.

Derby was delayed because of radome attenuation issues. How will one use BVR missile if radar signal not transmitting/received properly?

I know this has been discussed on BR earlier but im still unable to wrap my head ( despite all the explanantion provided by the experts here) around how we made a meal out a "simpler" element like the Radome when we so much experience in the RF field.
The issues with a RADAR i can understand but a radome i cannot ( given our extensive design base in these matters)

Anyways, hope there is a happy ending for all these hardwork put in since every nation has to go through these curves the 1st time

[Kailash]

Certification of radar based weapons and the radome (re)certification/modifications will come to bite the Uttam. Better keep Uttam aside for next few years and let it mature. A half baked Uttam won't help with operational numbers, and HAL will use it as an excuse for any delays in delivery.

[Viv S]

IN solved the problem quite easily regarding DRDO AIP. They allocated last two Scorpenes. However, when AIP program was delayed, they took a decision NOT to delay the Scorpene and proceeded with build minus AIP. Now AIP is proposed for Project 75I.

Why haven't they opted for the DCNS AIP solution (MESMA?) for the last two boats? Its a major planning failure, if that's the case.

Definitely a lesson in there for us vis a vis the Tejas and the Uttam.

[sum]

^^ IIRC, i recall reading long time ago( when the Scorpene deal were being finalised) that the DRDO had put its foot down and assured that no matter what, the AIP would be ready by the 5th boat and so, the import should be fully avoided since there was sufficient time to get it done.

I think the blame should be on DRDO and not on the IN which acted in good faith and showed trust in DRDO words that they didnt bother keeping backup ready. They put the money where the mouth is but were let down, i guess.

[Gyan]

Uttam should be used to upgrade a batch of Jaguars and then later for LCA. LCA is heavily delayed that using uttam in 83 aircraft does not make sense. Use Uttam for mk2

[Gyan]

It seems that apart from Gun, the integration of Derby & Python 5 is also work in progress and not fully concluded. No wonder IAF is internally livid. HAL is also not helping the cause by its snail pace.

[Gyan]

83 MK1A should be assembled as soon as possible even with imported Radar/components. Preferably by 2023. Order another batch of 80 MK1X where maximum indigenisation is the aim while perfecting MK2 & AMCA

[Marten]

It seems that apart from Gun, the integration of Derby & Python 5 is also work in progress and not fully concluded. No wonder IAF is internally livid. HAL is also not helping the cause by its snail pace.

Sir, could you please substantiate two items that you've said here:
1. IAF is internally livid.
2. HAL's snail pace.

[Bala Vignesh]

Uttam should be used to upgrade a batch of Jaguars and then later for LCA. LCA is heavily delayed that using uttam in 83 aircraft does not make sense. Use Uttam for mk2

Right, take a radar almost custom designed to fit the LCA and test it on a platform which has nothing even remotely similar to it!!
Gyanji, if you want things to proceed faster with Uttam then you can increase the no of aircrafts it is mounted on but not change the type completely. Furthermore, why would Uttam be stopped with just 83Mk1A?? We can and most probably will use it even on Mk2 with upgrades and any other upgrade program that comes along.

[Kakarat]

Saurav Jha‏ @SJha1618

2:55 PM - 26 Jul 2017 - The Uttam AESA though designed for the LCA is scaleable and is also meant for future mid-life upgrades of other aircraft like the Mig-29K.

[A Deshmukh]

If and when the Uttam is ready,
Order another 80 numbers of LCA Tejas Mk1B with Uttam radar.

[Pratyush]

Wow but knowing the penchant for overcommitment by DRDO I would believe it when the is accept Uttam as a viable radar.

[Manish_Sharma]

I think the blame should be on DRDO and not on the IN which acted in good faith and showed trust in DRDO words that they didnt bother keeping backup ready. They put the money where the mouth is but were let down, i guess.

Exactly!

Porkis are operating aip augusta subs for more than a decade, while we will be waiting for it a another 10 to 15 years due to DRDO's habitual overpromising. That too after so much delay in scorpene production. How casually they play with national security.

[Cain Marko]

As per Minister of state for Defence Subhash Bhamre statement in Parliament, FOC of LCA delayed to June 2018, may be FOC will be with MkIA configuration.

Source? Horrible news if confirmed. But dileep Saar did imply this.

[Indranil]

Although, sad if true, FOC doesn't matter. LCA MK1 is on a guide path. No structural modifications are foreseen. So they are ramping up production as planned. Qualification and addition of features will continue in parallel. This is exactly how it should be.

There are other things too.
1. Supersonic tanks of various sizes
2. Plumbing midboard pylon
3. Astra integration
4. Qualifying centerline pylon for things other than a DFT.
5. Better shaped (pinched) DFTs
6. Qualification with other smart weapons like SAAW

The plane is here for next 30-50 years. The list will go on. Production numbers shouldn't be held up because of such lists.

[Kartik]

Although, sad if true, FOC doesn't matter. LCA MK1 is on a guide path. No structural modifications are foreseen. So they are ramping up production as planned. Qualification and addition of features will continue in parallel. This is exactly how it should be.

There are other things too.
1. Supersonic tanks of various sizes
2. Plumbing midboard pylon
3. Astra integration
4. Qualifying centerline pylon for things other than a DFT.
5. Better shaped (pinched) DFTs
6. Qualification with other smart weapons like SAAW

The plane is here for next 30-50 years. The list will go on. Production numbers shouldn't be held up because of such lists.

Indranil, is that the list of items being worked upon by ADA/HAL/NFTC based on your discussions with sources or is it the list of things that you feel will need to be worked on?

I too agree that while disappointing to hear about the slide in FOC, one needs to keep in mind that even without an internal cannon or IFR, the Tejas Mk1 is a capable fighter. it is the production at desired rates that needs to be achieved and nothing should come in the way of that. Many of the much vaunted 4th gen fighters didn't get to their FOCs till they were well into squadron service.

[Cybaru]

Either Uttam is ready and that's great news or it's a rue to get a good price on the April tender.