Bharat Rakshak Forum Announcement

Hello Everyone,

A warm welcome back to the Bharat Rakshak Forum.

Important Notice: Due to a corruption in the BR forum database we regret to announce that data records relating to some of our registered users have been lost. We estimate approx. 500 user details are deleted.

To ease the process of recreating the user IDs we request members that have previously posted on the BR forums to recognise and identify their posts, once the posts are identified please contact the BRF moderator team by emailing BRF Mod Team with your post details.

The mod team will be able to update your username, email etc. so that the user history can be maintained.

Unfortunately for members that have never posted or have had all their posts deleted i.e. users that have 0 posts, we will be unable to recreate your account hence we request that you re-register again.

We apologise for any inconvenience caused and thank you for your understanding.

Regards,
Seetal

LCA: News & Discussions - October 2016

All threads that are locked or marked for deletion will be moved to this forum. The topics will be cleared from this archive on the 1st and 16th of each month.
Dileep
BRF Oldie
Posts: 5095
Joined: 04 Apr 2005 08:17
Location: Dera Mahab Ali धरा महाबलिस्याः درا مهاب الي

Re: LCA: News & Discussions - October 2016

Postby Dileep » 01 Aug 2017 06:48

Indranil wrote:
Dileep wrote:You people don't get it. MK2 ain't happening in any form. Plug, no plug, 0.5M plug, 1M plug, nothing. I get increasingly the feel that the mandate now is to finish the current platform. We have enough problems left with that one itself.

Maybe AamKa will get the required focus now, as some of the teams will be relieved from LCA side.

Dileep sir,

I know you can't speak of most things you know. But your sentences will be taken out of context here. Dooms day will forecasted. HAL/ADA would chastised. You know the drill :D


Indranil, anything said here at BRF has ZERO EFFECT, other than on jingo minds (and the jazoos who trawl here). I am pretty sure that the Netas, Babus and Soljers make their decisions based on the R&D we do here.

I am yet to see any connection to PAK-FA, but as Ramana put it, AamKa is the MK2. But the debate is still going on at the highest circles, so the fat lady hasn't sang yet.

One data point I can share about PAK-FA is that ADA folk pretend to barf when the name is mentioned. Mindsets are difficult to change you see? Uttam is still NIH at ADA as I notice.

NRao
BRF Oldie
Posts: 15866
Joined: 01 Jan 1970 05:30
Location: Illini Nation

Re: LCA: News & Discussions - October 2016

Postby NRao » 01 Aug 2017 07:08

Marten wrote:
ramana wrote:marten, What Dileep is telling us is LCA Mk2 will be AMCA.
No point is waiting for a marginal utility plane. By moving the design folks to PAK-FA and on to AMCA ensures design expertise is built up and not lost.

LCA Mk2 is a chance to redo the plane all over again.

Should have done it when moving from TD to Mk1.
That mid section 1 meter plug thing will effect aerodynamics all over again.

Its time now not money that is the driver.

Would be happy to see AMCA FSED being funded first. 90 cr from what I was told. And even that is being criticized. I understand the reason but developing the second iteration single engine MK 2 would always be the shortest delivery path. Whether the IAF sees potential or gain is a different matter. If MK1a would meet IAF requirements for a single engine fighter, nothing like it. At the moment, it appears otherwise.

AMCA deserves focus and energy but one wouldn't be surprised to see it cast aside in five years. I simply cannot see ADA back pedal on the path breaking all aspect stealth and related technologies. My limited and perhaps illiterate point is that we can and should go in for another twin engine jet without the trappings of stealth. Let us rapid prototype what we can make with technology on hand. From MK 1, 1a and if it happens, MK 2.



Feb 5, 2017. GoI clears funds for AMCA. Read somewhere that the work common to both teh Ghatak and AMCA has commenced.

I do NOT believe the AMCA is MK2. They are two totally different beasts -as they should be (I think there are two distinct teams - LCA and AMCA). What I do see transferring over is the knowledge gained from the LCA - management of real-state, etc, not so much the technologies.

UlanBatori
BRF Oldie
Posts: 8683
Joined: 11 Aug 2016 06:14

Re: LCA: News & Discussions - October 2016

Postby UlanBatori » 01 Aug 2017 07:40

After reading all these miles of posts these past several dins, my respect for the Indian system of defence secrecy has risen higher than the Doklam Ridge. Sooo much noise, yet not a single postor seems to have a clue about the real forces / compulsions behind the various announcements, alliances etc. And far be it from me, a simple yak-herder to reveal what one hears on the breezes rising from where the Royalty bee.

But for the same reasons, I worry a lot about the LCA. If you think way back to 1992/94, do you recall announcement of joint development of LCA? As price for India "giving up" ICBM development? Do you know what that was all about? I guessed much of it and I was right.

The development of the LCA has much in common with the story of the Mouse On The Moon. The poor thing was an orphan from birth.
Last edited by UlanBatori on 01 Aug 2017 07:43, edited 1 time in total.

Singha
BRF Oldie
Posts: 60468
Joined: 13 Aug 2004 19:42
Location: Lupine but moderately dharmic

Re: LCA: News & Discussions - October 2016

Postby Singha » 01 Aug 2017 07:43

it is too late to design and build a 'definitive' 4.5 gen fighter ie Mk2 for FOC in 2025 isnt it.

whatever we name it , the next fighter IOC 2030 latest has to be feature internal bays, LO, updated aesa radar, the best spherical defensive aids and a family of domestically owned munitions with only the engine being license made and a few things like MFD and ejection seat cots.

so AMCA it has to be and they have to get cracking. its a tough schedule from design freeze to 1st flight with proven systems in 7 yrs.

whatever is inadequate in the Tejas will need to be fixed in the next. but its too late for a Tejas MK2 to enter volume production. they could still run it as a science project to test the AMCA concepts and subsystems to speed things up for which Mk1A airframe will suffice. the internal bay could be tested using a SU30 if they are creative.

NRao
BRF Oldie
Posts: 15866
Joined: 01 Jan 1970 05:30
Location: Illini Nation

Re: LCA: News & Discussions - October 2016

Postby NRao » 01 Aug 2017 07:57

I just do NOT see why the LCA and AMCA cannot share "stuff". The LCA MK1A does not have to stop exactly at the last alpha in the last sentence in the last para of some report sitting some place. What is preventing them from developing smaller and more sensitive sensors that can be shared by both - flush mounted sensors? The potential for the MK1A is humongous. And, so is it for the AMCA. Just hope they do NOT tie them up, nor restrict them to some preconceived ideas. With the end of a Mk2 - in any form - the LCA has another 40 years of life. Let it live with newer and greater things every year!!! Do not see a need for any doom-N-gloom for the LCA. It has a very bright future - as long as one does not stick to some old thinking.

To be SURE - they both (LCA and the AMCA) are two totally different planes. So far, they also have two totally diff teams too.

UlanBatori
BRF Oldie
Posts: 8683
Joined: 11 Aug 2016 06:14

Re: LCA: News & Discussions - October 2016

Postby UlanBatori » 01 Aug 2017 08:03

Singhaji, I don't see why India does not crank out a few hundred LCAs just for the heck of it- of course after the indigenous engine is available. Send them spread out all over the nation and the Lakshadweep and Andaman-Nicobar. These don't have to be stealth/Gen5 airsuperiority fighters, just deadly interceptors that can destroy various kinds of threats. I don't see the point of this endless deliberation like the Search For The Real Princess. If you have to send up a couple of fighters to catch a biz-jet, you don't need a Gen5 fighter. Anything with an aimable gun will do.

NRao
BRF Oldie
Posts: 15866
Joined: 01 Jan 1970 05:30
Location: Illini Nation

Re: LCA: News & Discussions - October 2016

Postby NRao » 01 Aug 2017 08:17

UB ji,

I had refrained, in the SE thread, to make this comment.

There are essentially three phases to this "process": the MIC, the production (including scaling up) and the user/client.

The problem with what you are proposing is that in the "user/client" domain the mantra is see first, shoot first. Can your solutions/proposals do that? And, i do not mean plane v. plane. I am not comparing a 4th gen LCA with some 5th gen, LO plane. Can Indian assets - under ANY circumstances - "see first"? IF they can then, yes, then build only 4th/3rd gen planes.

UlanBatori
BRF Oldie
Posts: 8683
Joined: 11 Aug 2016 06:14

Re: LCA: News & Discussions - October 2016

Postby UlanBatori » 01 Aug 2017 08:24

The US maintains a huge force of aerial assets. Very few of these are F-22s or F-35s, all formally inducted into USAF first-line squadrons. The bulk of the heavy lifting is done by F-15s and F-16s which are 1960s designs. Many of the planes are actually given to state National Guard units, but can be called up when needed. Thus there is a huge dispersed force. In India, outside the IAF active units, what is there except a lot of mouths yakking?
Yes, if an LCA goes up to pursue a subsonic biz-jet or a smuggler's dhow or 3 pakis in a dinghy, I sure hope the LCA can see and shoot first.

vnms
BRFite
Posts: 165
Joined: 15 Aug 2016 01:56

Re: LCA: News & Discussions - October 2016

Postby vnms » 01 Aug 2017 08:33

NRao saar, wouldn't awacs/ground radar systems help to see/paint tangos? Otherwise, what exactly is the point purpose of awacs etc.? They should be able to feed data to any bvms on the lca. What am I missing here?

NRao
BRF Oldie
Posts: 15866
Joined: 01 Jan 1970 05:30
Location: Illini Nation

Re: LCA: News & Discussions - October 2016

Postby NRao » 01 Aug 2017 08:33

Let us keep the "US" out of this discussion (actually, IMHO, a US 5th Gen is more about sharing info than not being seen). That is a totally diff beast - designed to fight far from their shores. Not even the Russians or Chinese are as good at it yet (including Russia is Syria) - in fact let me go out on a imb and state that even Israel is better than these two).

Leave Pakis out too - they are a province of China (might as well grant that if we can grant Tibet).

So, you thing a LCA will "see first"? India has sufficient assets to detect intrusion at sufficient distance to tackle a problem and therefore not field a "5th gen" (whatever that means) to counter?

NRao
BRF Oldie
Posts: 15866
Joined: 01 Jan 1970 05:30
Location: Illini Nation

Re: LCA: News & Discussions - October 2016

Postby NRao » 01 Aug 2017 08:42

vnms wrote:NRao saar, wouldn't awacs/ground radar systems help to see/paint tangos? Otherwise, what exactly is the point purpose of awacs etc.? They should be able to feed data to any bvms on the lca. What am I missing here?


Well ......................

The question is who sees whom first.

Indian opponents have AWACS too. So, do Indian AWACS see the opponents first or do they see Indian assets first?


Which brings us to the crux of the discussion: Is it better for India to field 1000 4+/4++ gen planes of some 200/300 5th Gen planes (given that China will field some 100+ 5th gen planes)?



I, humbly, would add sensors and network to the list provided by GD.

Manish_Sharma
BRF Oldie
Posts: 3870
Joined: 07 Sep 2009 16:17

Re: LCA: News & Discussions - October 2016

Postby Manish_Sharma » 01 Aug 2017 08:52

I have posted a question here:

viewtopic.php?f=3&t=7261&start=4040#p2193243

vnms
BRFite
Posts: 165
Joined: 15 Aug 2016 01:56

Re: LCA: News & Discussions - October 2016

Postby vnms » 01 Aug 2017 08:54

If the f-22 is more or less used as an awacs platform, then which type of planes would be fed this info? Surely, they would be < 5 th gen aircraft. Then, we end up in the same situation where the enemy might not detect the f-22, but will be able to detect the others. No country can afford to have only 5th gen. As long as there are other 4/4.5 gen aircraft, equivalent fighters will have a role and a chance

NRao
BRF Oldie
Posts: 15866
Joined: 01 Jan 1970 05:30
Location: Illini Nation

Re: LCA: News & Discussions - October 2016

Postby NRao » 01 Aug 2017 08:59

Do not know about you guys, but here is my thinking on the Mk1A:

2018-19: native radar
2020: LCA weight loss due to 3-d printing of landing gears. Native missiles
2021: Flush mounted sensors
2021-22: 360 degree radar coverage. Integration of Kaveri (f404 specs)
2022: 5th Gen composite skin
2024: missile to counter A2A missile
...........................................

negi
BR Mainsite Crew
Posts: 12908
Joined: 27 Jul 2006 17:51
Location: Trying to mellow down :)

Re: LCA: News & Discussions - October 2016

Postby negi » 01 Aug 2017 09:02

If we do not 'COMPLETE' LCA and jump onto AMCA it will be just another science project and the deficiencies which have not yet come to light will become blockers in a new project , I have seen this too many times in product development . Teams that have delivered successful working products are fine leaving projects half done due to viability or technical reasons for they can take that judgement call based on experience but a team that is developing it's first maiden fighter should not get distracted by a future fighter project this is where we fail . Everyone wants to only do Research>Development>Operationalise>Manufacture in that order of precedence . We are stuck in first 2 stages and with Tejas we have only mastered first 2 stages the last 2 are yet to be mastered without doing that for Tejas we should not even move to another fighter unless the platform is deemed constrained or nonviable for production otherwise we will repeat same shit with AMCA.

ISRO never moved to GSLV until it had established a reputation with the PSLV even to this day it continues to improve the PSLV , although it is a slightly different space than military AC but the point is one needs to first learn how to crawl and walk before committing to run. Our budgets will always be small , we will never have multiple R&D entities like LM, Boeing, GD there will be only one ADA and HAL for foreseeable future then how do you suppose parallel projects will be delivered ? Sure designers and researchers will be happy for they will get to hop on and off from one project to another and that is why these will only lead to science projects.
Last edited by negi on 01 Aug 2017 09:14, edited 1 time in total.

NRao
BRF Oldie
Posts: 15866
Joined: 01 Jan 1970 05:30
Location: Illini Nation

Re: LCA: News & Discussions - October 2016

Postby NRao » 01 Aug 2017 09:04

vnms wrote:If the f-22 is more or less used as an awacs platform, then which type of planes would be fed this info? Surely, they would be < 5 th gen aircraft. Then, we end up in the same situation where the enemy might not detect the f-22, but will be able to detect the others. No country can afford to have only 5th gen. As long as there are other 4/4.5 gen aircraft, equivalent fighters will have a role and a chance


The problem I have with quoting F-22/F-35 is that that US designs things to be used way out from their shores. They have their entire systems geared for global deployment. I just do not know of any other nation that has that in their thinking, forget designs, etc.

For that reason alone I would keep the F-22/F-35 out of the discussions.

NRao
BRF Oldie
Posts: 15866
Joined: 01 Jan 1970 05:30
Location: Illini Nation

Re: LCA: News & Discussions - October 2016

Postby NRao » 01 Aug 2017 09:15

: )

negi ji,

Understand your frustration. But, would like to beg to differ. In the three-phase mode I posted above (MIC/production/client), I think, the first (MIC) (granted there are some teething issues with the MK1A) and third (IAF) are fine, it is the second that has issues. Unable to throttle scaling. ??????

The AMCA is in the first stage. And, if at all, it is the best one in India. Let them drive and let us see what happens. The entire (three phase) system is not rotten (actually none of them are). In fact, I would argue that the MIC/design is THE best one.

Singha
BRF Oldie
Posts: 60468
Joined: 13 Aug 2004 19:42
Location: Lupine but moderately dharmic

Re: LCA: News & Discussions - October 2016

Postby Singha » 01 Aug 2017 09:57

Tejas M1A can continue to be improved on with new sensors and weapons just like the F16 has gained its bulges and CFTs but the basic airframe and wing and FCS has remained the same. so costly and time consuming stuff like fuselage plug and new big wing can be deleted but rest including engine change can be tried out, with some bigger inlets. call it 1B, 1C .... 1F
and naturally all the AMCA sensors must first be tried out on Tejas 1x and Su30.

production run in this mode can be 400 and replace all the jaguar, Mig29 and mig27 also not just the Bisons. anything in that size the tejas can do better if developed and funded properly. NO MORE RAFALES SHOULD BE PURCHASED.

Tejas can be rigged as a flying testbed to test the FCS of the AMCA also, which will help us get exp in that domain and build our own zhukovsky, nasa dryden flight research lab. no more F16XL leasing.

by the time AMCA chassis is flight tested and engines qualified, the rest of building blocks should all be ready via Tejas1x

monkey in ointment is the MII F-solah which can take a lot of numbers out of that 400 !!

Manish_Sharma
BRF Oldie
Posts: 3870
Joined: 07 Sep 2009 16:17

Re: LCA: News & Discussions - October 2016

Postby Manish_Sharma » 01 Aug 2017 10:39

Image

How about a joint program with LM to develop Tejas XL, on lines of Brahmos between Bharat and Russia?

Original Tejas fly by wire was tested on f16xl and performance was better then it's own FBW.

With f135 engine from f35.

While ADA and LM develop it and Tata-LM mfr it. We can place order of 270 fighters plus 45 twin seat trainer.

LM produces 16 in USA per year and 16 in Bharat per year with f35 composites.

Singha
BRF Oldie
Posts: 60468
Joined: 13 Aug 2004 19:42
Location: Lupine but moderately dharmic

Re: LCA: News & Discussions - October 2016

Postby Singha » 01 Aug 2017 11:29

thats not a bad idea if we can rope in LM for Tejas XL but the deal is peanuts when they have 4000 JSF to make. and too many congress imposed laws on tech sharing that not even a friendly potus can bypass. americans are tigerish about safeguarding their crown jewels.

Saab might be onlee one interested, I assume you do not want Mig :) but then if we want Saab why not make them consultant for AMCA, the swedes might also be interested in a new design post gripen and we can share the work and risks. amca is not too small or too big and should be ok for sweden needs. we can definitely have a common chassis and fcs and electrical system and perhaps american engine. beyond that sensors and weapons can be country specific pkgs with some common core engines.

russia, france, usa are just too strong technically to ever tolerate a junior partner or throw meaty chunks. all we will get is bones like FGFA leftovers.

brar_w
BRF Oldie
Posts: 5997
Joined: 11 Aug 2016 06:14

Re: LCA: News & Discussions - October 2016

Postby brar_w » 01 Aug 2017 15:35

Lockheed obviously won't be interested in producing anything since they have their portfolio but of course under the right circumstances they have worked with foreign OEMs and countries on 5th generation technology which they have control over. Both South Korea and Japan requested and obtained 5th generation test data (wind tunnel data) and design engineering support as part of their F-35 offsets and as the article posted by kartik in the Int. thread shows, they have a few dozen engineers permanently embedded with the KAI design team.

But for such a path to be pursued with Lockheed or any other global player the MOD must first move away from the SE program that they currently plan on pursuing and begin to think about how to accelerate the AMCA so that it can arrive by the early to mid 2030s. From prototype to IOC is a good 15 year process for 5th generation aircraft even for the most experienced OEMs out there so efforts should be initiated now to make sure that the IAF has the AMCA at the squadron level by the early to mid 2030s. The way things are going, unless AdA and HAL can design, develop and test at a pace not shown by any other advanced fighter program out there, the AMCA appears to be a mid 2030 - late 2030s platform. This may be an area where one can cooperate and move things along.

Manish_Sharma
BRF Oldie
Posts: 3870
Joined: 07 Sep 2009 16:17

Re: LCA: News & Discussions - October 2016

Postby Manish_Sharma » 01 Aug 2017 17:07

Singha wrote: I assume you do not want Mig :) but then


But mig won't have bigger engine like F135.

Maybe 117S of FGFA might work. But do Russian mic have experience with Tejas / f16xl styled cranked Delta platform? I wouldn't mind a Brahmos type jv with russkies on this too....

I mean what an amazing range of possibility:
. The increase in internal volume (both by lengthening the fuselage and expanding the wing) allowed for a 82% increase in internal fuel capacity, while the increased wing area allowed the incorporation of up to 27 stores stations. :shock: Despite the apparent lengthening of the fuselage involved with the program, the new XL designation does NOT stand for "extra large".
Through wing planform improvements and camber optimizations, the final configuration offered a 25% improvement in maximum lift-to-drag ratio over the F-16 supersonically, and 11% improvement subsonic. The handling of the F-16XL was reportedly quite different from that of the standard F-16, offering a much smoother ride at high speeds and low altitudes. The configuration had matured into a very competent fighter with a large wing that allowed low-drag integration of large numbers of external weapons.
http://www.f-16.net/f-16_versions_article1.html


27 stores; imagine spice, garuthma showering on porkis

UlanBatori
BRF Oldie
Posts: 8683
Joined: 11 Aug 2016 06:14

Re: LCA: News & Discussions - October 2016

Postby UlanBatori » 01 Aug 2017 17:27

GE F136 engine. I think Orange Bandar will sell that to India. Also, F136 production in India will be approved, and even USAF may buy that back for some applications. LCA with F136 can be a very potent combo.

JayS
Forum Moderator
Posts: 2718
Joined: 11 Aug 2016 06:14

Re: LCA: News & Discussions - October 2016

Postby JayS » 01 Aug 2017 17:30

Manish_Sharma wrote:
Original Tejas fly by wire was tested on f16xl and performance was better then it's own FBW.



It wasn't F16XL, but regular F16 with modified version called VISTA - (Variable Stability In-Flight Simulator Test Aircraft). F16XL itself was a Science project with limited maturity. How could it be used for testing FBW for other aircrafts..?

Dome details here:

http://www.calspan.com/wp-content/uploa ... v-1-13.pdf

Manish_Sharma
BRF Oldie
Posts: 3870
Joined: 07 Sep 2009 16:17

Re: LCA: News & Discussions - October 2016

Postby Manish_Sharma » 01 Aug 2017 19:47

UlanBatori wrote:GE F136 engine. I think Orange Bandar will sell that to India. Also, F136 production in India will be approved, and even USAF may buy that back for some applications. LCA with F136 can be a very potent combo.


Is it that contra rotating design that you mentioned in Turkey jsf thread?

UlanBatori
BRF Oldie
Posts: 8683
Joined: 11 Aug 2016 06:14

Re: LCA: News & Discussions - October 2016

Postby UlanBatori » 01 Aug 2017 20:58

I think GE136 is also contra-rotating. Only way to reach such extreme T/W, but it makes sense: you basically halve the mass by eliminating the stators, and you can probably push the stage pressure ratio a lot higher. The oft-cited show-stopper is resonance, but apparently that can be fixed. For instance, Kamov and Sikorsky X2 are now contra-rotating (much lower speed I agree) and seem to have no resonance issues. GE 136 is basically in the doghouse, Pentagon flatly refused to consider it as a "second source" for HSF. So GE is sitting on $$B worth of R&D investment. Ripe for export to friendly nation.

vina
BRF Oldie
Posts: 6018
Joined: 11 May 2005 06:56
Location: Doing Nijikaran, Udharikaran and Baazarikaran to Commies and Assorted Leftists

Re: LCA: News & Discussions - October 2016

Postby vina » 01 Aug 2017 21:51

UlanBatori wrote:I think GE136 is also contra-rotating. Only way to reach such extreme T/W, but it makes sense: you basically halve the mass by eliminating the stators, and you can probably push the stage pressure ratio a lot higher. The oft-cited show-stopper is resonance, but apparently that can be fixed. For instance, Kamov and Sikorsky X2 are now contra-rotating (much lower speed I agree) and seem to have no resonance issues. GE 136 is basically in the doghouse, Pentagon flatly refused to consider it as a "second source" for HSF. So GE is sitting on $$B worth of R&D investment. Ripe for export to friendly nation.


The stators are very much there. What gets recovered is the rotation losses in the gas path (giving better efficiency and hence thrust and fuel burn) and better gyroscopic imbalances. That is good for single engine planes and also in fact if don't need to dedicated engines on the left and right for multiengine planes (like they make the props spin in opposite directions on the left and right) .

In fact rather than the Kamov / Sikorsky, the engine you really want to look as the model for the PW 119 , the PW 135 and the GE analogs is the Rolls Royce-Bristol Pegasus engine of the Harrier (yes, the IN used it too). It flew first around 50 years ago nearly and it uses a contra rotating spool. The LP spool spins one way, the HP spool spins the other way. So yeah, not exactly "new" . But that Pegasus engine was truly an engineering marvel back then and so does it remain to this day. Brit engineering innovation at it's best.
Last edited by vina on 01 Aug 2017 21:57, edited 1 time in total.

UlanBatori
BRF Oldie
Posts: 8683
Joined: 11 Aug 2016 06:14

Re: LCA: News & Discussions - October 2016

Postby UlanBatori » 01 Aug 2017 21:57

OT, but I can draw the velocity diagrams with no stators for these (as they say, everything is possible in computer graphics..), hain? If the swirl can be recovered, and the rotors are, say, "50% reaction", the static pressure rise is also achieved, IIRC with no need for stators. May be difficult to do over a range of conditions in a compressor but certainly feasible in a turbine. True that the old engines may have used LP and HP in opposite directions, that would be purely to remove the torque. Are reliable pics of either F135 or F136 available? The patents show counter-rotating but very confused about the rest of the details. The usual PR pics are exactly that. I don't think the engine core is advertised much.

vina
BRF Oldie
Posts: 6018
Joined: 11 May 2005 06:56
Location: Doing Nijikaran, Udharikaran and Baazarikaran to Commies and Assorted Leftists

Re: LCA: News & Discussions - October 2016

Postby vina » 01 Aug 2017 22:12

UlanBatori wrote:OT, but I can draw the velocity diagrams with no stators for these (as they say, everything is possible in computer graphics..), hain? If the swirl can be recovered, and the rotors are, say, "50% reaction", the static pressure rise is also achieved, IIRC with no need for stators. May be difficult to do over a range of conditions in a compressor but certainly feasible in a turbine. True that the old engines may have used LP and HP in opposite directions, that would be purely to remove the torque. Are reliable pics of either F135 or F136 available? The patents show counter-rotating but very confused about the rest of the details. The usual PR pics are exactly that. I don't think the engine core is advertised much.


Yes. But the heavy multi stage part is the compressor and that is where the biggest gains in weight come if you manage to reduce stators. The turbines are rather small and light weight in comparison. Like you said, the compressors will need a few stator stages for sufficient surge and stall margins against distorted flow, especially in a fighter. Probably fewer stators than earlier, but not zero maybe.

In addition to the torque effect, the gyroscopic effects are also there. The fast spinning high rotational inertia stuff sets up huge gyroscopic effects and makes the plane super stable in one direction . Like the Rotary engines of the WW1 days, where the entire engine cylinder block rotated while the crankshaft was fixed (the prop was fixed to the cylinder block) . That kind of thing sets up humongous rotational inertia and gyroscopic effects.

For e.g., the Sopwith camel would do a roll in an blink of an eye in one direction and simply be resistant to roll in the opposite (when radial engines came about, with cylinders fixed and crank rotating, the effect got mitigated largely, but still exists) . You really don't want that kind of stuff in a nimble fighter . For the harrier with all the hovering and stuff it was important and they went that way.

UlanBatori
BRF Oldie
Posts: 8683
Joined: 11 Aug 2016 06:14

Re: LCA: News & Discussions - October 2016

Postby UlanBatori » 01 Aug 2017 22:26

Never thought about the rotational inertia. Yes, counter-rotation is the way to go then.

Manish_Sharma
BRF Oldie
Posts: 3870
Joined: 07 Sep 2009 16:17

Re: LCA: News & Discussions - October 2016

Postby Manish_Sharma » 09 Aug 2017 19:15

idrw.org .Read more at India No 1 Defence News Website http://idrw.org/tejas-continues-to-face ... ry-delays/ .



Tejas Continues To Face Delivery Delays

Published August 8, 2017

SOURCE: ULTRA NEWS



Hindustan Aeronautics Ltd or HAL continues to run well behind schedule in delivering India’s first indigenous jet fighter, Tejas Mark I. The government-controlled company was supposed to have delivered four Tejas Mark I aircraft by March 2016, and a total of 12 by March 2017, and the entire 20 in the first lot were supposed to have been delivered by March 2018. Instead, according to defence ministry data, the company has delivered only four Mark I aircraft so far. It has another 12 under production. India needs around 300 light combat jets, out of which HAL is supposed to supply 40 in the form of Mark I jets — the first ‘generation’ of the aircraft. From 2019 onwards, HAL is supposed to work on supplying another 83 upgraded version of the model, called Mark 1A. However, according to current timelines, the company is likely to start production of the improved version only by 2021. Instead of Mark IA, HAL was supposed to have worked on the larger and more advanced Mark II. However, the company in 2015 told the government it didn’t have the manpower to focus on the production of the Mark I and, at the same time, develop the second generation. As a result, the responsibility for the second generation is being handled by Aeronautical Development Agency or ADA, a wing of the Defence Research and Development Organization. There has been considerable competition between the DRDO and HAL on the project. Last month, the defence ministry even got an unsigned letter alleging that HAL’s move to float a global tender to buy an electronic array radar instead of waiting for DRDO’s version amounted to wastage of public money. Meanwhile, DRDO’s ADA wing is going full speed on developing Tejas Mark II, and HAL faces the risk that if Mark II is ready by 2022-23, it could affect the demand for the IA version.

idrw.org .Read more at India No 1 Defence News Website http://idrw.org/tejas-continues-to-face ... ry-delays/ .

Indranil
Forum Moderator
Posts: 5853
Joined: 02 Apr 2010 01:21

Re: LCA: News & Discussions - October 2016

Postby Indranil » 09 Aug 2017 20:22

The above report is full of mistakes.

Khalsa
BRFite
Posts: 1015
Joined: 12 Nov 2000 12:31
Location: NZL

Re: LCA: News & Discussions - October 2016

Postby Khalsa » 10 Aug 2017 01:45

No. 1 defence site ??
Ahem Cough Okay Jee

Kartik
BRF Oldie
Posts: 3508
Joined: 04 Feb 2004 12:31

Re: LCA: News & Discussions - October 2016

Postby Kartik » 11 Aug 2017 05:28

Ignore the rubbish about "further delays" and concentrate only the important snippets from this article on Janes

link

The Indian Ministry of Defence (MoD) has revealed further delays in the country’s programme to produce the Tejas Light Combat Aircraft (LCA) for the Indian Air Force (IAF).

The MoD said in a statement on 4 August that state-owned Hindustan Aeronautics Limited (HAL) has delivered just four aircraft to the IAF out of 40 ordered in 2005. All these aircraft were previously scheduled to be delivered to the IAF by 2017–18.

The four aircraft so far delivered are from a batch of 20 designated for initial operational clearance (IOC), while the remaining 20 aircraft were designated for final operational clearance (FOC).

The MoD said that 12 remaining aircraft under the IOC batch are at the production stage and four more aircraft, which will be used as trainers, will be produced following necessary approvals by the MoD’s Aeronautical Development Agency (ADA).


It added that production of the 20 FOC aircraft will also depend on clearance by the ADA, which has led the Tejas development programme for the past three decades.

The MoD said that HAL has undertaken a raft of initiatives to increase the production rate of the Tejas LCA.

These include, it said, HAL obtaining authorisation in March 2017 from the government to ramp-up production capacity from eight to 16 aircraft per year, and the establishment of a second manufacturing line to support “structural and equipping activities”.

HAL has also increased the number of jigs involved in manufacturing the aircraft’s front fuselage, centre fuselage, rear fuselage and wings, and reduced the manufacturing cycle time by improving supply chain management and boosting workforce.



SaiK
BRF Oldie
Posts: 35369
Joined: 29 Oct 2003 12:31
Location: NowHere

Re: LCA: News & Discussions - October 2016

Postby SaiK » 11 Aug 2017 05:36

Delays, corrections, changes are perfectly valid. But what we have learned from them, and how we have successfully avoided redoing the same mistakes should be given prime importance. Production Engineering is the area we need to advance a lot.

Rakesh
Forum Moderator
Posts: 4109
Joined: 15 Jan 2004 12:31
Location: Planet Earth
Contact:

Re: LCA: News & Discussions - October 2016

Postby Rakesh » 11 Aug 2017 06:06

SaiK: I agree with you, however Kartik is referring to delays mentioned in the article. Much ado about nothing.

ArjunPandit
BRFite
Posts: 650
Joined: 29 Mar 2017 06:37

Re: LCA: News & Discussions - October 2016

Postby ArjunPandit » 11 Aug 2017 06:23

Khalsa wrote:No. 1 defence site ??
Ahem Cough Okay Jee

As per server owner's mom!
That said, with every passing day the SE fighter deal does not happen, the chances of tejas brightens. If this govt gets 2019 (which it would), then the propsects of Tejas would be even brighter

samirdiw
BRFite -Trainee
Posts: 91
Joined: 18 Jul 2017 22:00

Re: LCA: News & Discussions - October 2016

Postby samirdiw » 11 Aug 2017 08:32

Considering the IAF has high standards for LCA, can the LCA Mark 1 be useful for IA in CAS role? If yes this could really help our strike corps ?

Also, why can't IAF ask for a couple more squadrons of LCA1, get training in it, give feedback and then rotate them out with Mark 2 or get them upgraded similar to early Sukhoi's as and when the tech/integration becomes available?

Gyan
BRFite
Posts: 913
Joined: 26 Aug 2016 19:14

Re: LCA: News & Discussions - October 2016

Postby Gyan » 11 Aug 2017 08:50

What is the Status of SP-5? Any news??

Bhaskar_T
BRFite
Posts: 233
Joined: 13 Feb 2011 19:09

Re: LCA: News & Discussions - October 2016

Postby Bhaskar_T » 13 Aug 2017 10:47

Bro SP-5, at least do a LS/HS taxi run on 15th August. Jai Hind.


Return to “Trash Can Archive”

Who is online

Users browsing this forum: No registered users and 1 guest