LCA News and Discussions

[geeth]

Many of the marine GTs are aero derivatives, including the Olympus engine used in Concorde aircraft. It is not too difficult and saves time&money

[vic]

IIRC

F404 J series Max power 78Kn but max war setting 84kn

F404 IN 20 Max power 84kn but max war setting 91kn

F414 S6 Max Power 98kn but war setting ?? Can be upto 104-108kn

[Singha]

HAL must have moved people into Tejas mk2 project. there seems to be a team from project director downward for it. without success in Tejas mk2 , the AMCA is a impossible goal in many respects.

Cheen went through that curve working on the J-10a,b,c......they are about a decade ahead of us in aerospace and throwing more resources into it.

[NRao]

23.04.2013
India's Ministry of Defense has suspended the implementation of the project fighter of the fifth generation AMCA to accelerate the completion LCA «Tejas"

HAL must have moved people

Yes, and we discussed the topic when it was announced too.

without success in Tejas mk2 , the AMCA is a impossible goal in many respects.

How so? Do we have data points for us to make such statements? Curious, that is all. I have not come across much commonality outside of materials to make the body and a few other items. The AMCA is a FbL (as far as we know) and that by itself has to make the two very, very, very different - computers, hardware, etc. Even the cockpits (again, from what we know so far) is night and day apart.

Outside of very few items I just do not see any dependencies. If people know what they are I would appreciate more info (A topic for the AMCA thread for sure - not here). TIA.

[SaiK]

Yes.. we have plenty of data points to provide NRao.. we can only graduate learning from one device going operational to another. We are talking capability that can only be measured from actual use. It is very valuable dataset that is mandatory for the next platform.

Rest is all R&D, and not platforms.

[NRao]

My question still stands.

[Sagar G]

The applications are basically for missiles, to lower weight & make them more compact. They are the volume, weight, space constrained designs that critically need SOCs with as many functions combined.

In contrast, the LCA's MC will have to be more complex and powerful, it has to handle all the nav-attack computations with multiple sensors in real time (as versus preprogrammed waypoints and only executing those), but it also drives display symbology, controls more sensors and does functions like data fusion (intended for MK2 per reports).

You are right garu, what caught my eyes was the word "mission computer". I have never come across any article using that word for a missiles computer and RCI chief also doesn't mention specifically that the SOCs are missile specific only. Sample this old article by Anantha Krishnan M.

Indian missiles are set to go lighter and smarter with the Defence Research and Development Organisation (DRDO) on the verge of launching a System on Chip (SOC) component, to be embedded on to the onboard computer (OBC). The SOC will give a tech advantage to the scientists to either increase the range of the missile or the warhead, depending upon the mission. The processing speed also will go up by 6-7 times with SOC.

A five-member team of young scientists with average nine years of experience are eagerly waiting for the final product, which will replace the PCB-based hardware consisting of various integrated components (IC) on single board. A missile typically carries huge number of such ICs making the total weight of the OBC close to 4-5 kilograms. The SOC with its power supply unit and connecters will weigh less than 200 grams.

DRDO scientists claim that it will be for the first time India will equip its missiles with such state-of-the-art component, though the US, Israel and China have made inroads in similar technologies. SOC will be a match-box size unit with high computing intense application and very low power requirement. The efficiency of the missile will also be increased by many folds.

S K Ray, Director, Research Centre Imarat (RCI), tells Express that miniatirisation of systems makes the missile high-performance in nature. “Smaller avionics means, more options for warhead with more propulsion. Ours chips can be used for avionics applications in future too and we have a huge cost advantage having made them indigenously. It will be an integral part of all future navigation and homing guidance seekers,” says Ray.

B H V S Narayana Murthy, Director, Real-Time Embedded Computers, RCI, says that the might of India’s futuristic missiles will largely depend on miniaturization of onboard systems. “The key developing smaller and efficient components and India is in striking distance in achieving this. Tactical missiles will be the biggest beneficiaries and we are now aiming to standardize and offer SOC to more platforms in future,” Murthy said.

As you can see that it hasn't been clearly stated that the SOCs are meant for the missile avionics only but they are talking about "future avionic application" and "offering SOC to more platforms". I think there is a fat chance that LCA might get SOC based avionics (in the future of course).

[SaiK]

you should get answers from no data points exists within the country. so we need to build it up. we have already burned ourselves in establishing the baseline capabilities.. and now we want to stage it from there. operational platform gives tremendous capabilties,.

from public sources, f-16 is the best example, that from which other capabilities and platforms were developed.

[vishvak]

So we are bankrolling Boing engine F414 from USA now. Hopefully the Govt should be providing at least more than this much to the Kaveri engine project, and not stop looking at other options available for LCA/AMCA.

[NRao]

So we are bankrolling Boing engine F414 from USA now. Hopefully the Govt should be providing at least more than this much to the Kaveri engine project, and not stop looking at other options available for LCA/AMCA.

Thanks to the EADS folks, of course. Else we would be "bankrolling" them instead.

BTW, the Kaveri project was detached from the LCA some time back. Best hope now is the AMCA-Kaveri hookup. Perhaps Kaveri-LCA in mid-life upgrades? But WRT the GE they are two different accounts.

And, WRT "bankrolling" the F414 - nope. The USN has already done that part and GE IIRC has also come out with a alternative fuel engine that they tacked on to a F-18 (it worked, but IIRC it was found to be too expensive for the moment). So the INS6 was specifically modified for the ADA - the dev work is done, the cost being paid is what it is and I do not thin anyone else is using this engine.

[vishvak]

If I am not mistaken, cost of engine RnD is paid for by sales during its lifetime. Especially if no one else is using it as also if it is used elsewhere. It is like saying we are paying for Rafael as it is, however cost of development is part of price of product.

[NRao]

Fundamentally you are right, no two ways about it.

But, it is not as bad as it looks. The INS6 was an extrapolation of an very reliable existing engine - so the dev costs were low, low enough to be L1 (EADS may/will contest that). I agree with what you are saying, just that the INS6 is not an AL-55I, where India paid for everything, the product was not debugged and the developer potentially can still make more money with India getting nothing out of it.

[Brando]

HAL must have moved people into Tejas mk2 project. there seems to be a team from project director downward for it. without success in Tejas mk2 , the AMCA is a impossible goal in many respects.

Cheen went through that curve working on the J-10a,b,c......they are about a decade ahead of us in aerospace and throwing more resources into it.

Iterative development and improvement of a system is far easier than building it from scratch. Once FOC is achieved for the Mark 1, the Mark 2 will inevitably materialize. The AMCA project in contrast is FAR more ambitious (at least on paper) to what they have done so far and it will require them to dig deep to deliver.
With the cost of 5th generation platforms sky rocketing to obscene heights, the wisdom of going it alone on the AMCA is somewhat suspect. There are a LOT of other nations sitting on the fence with their own "5th generation" fighter aircraft like the SoKo's, the Nipponese and even the Turks. The combined resources of one or even two of these nations could produce something quite substantial and offer these countries an alternative to American dependence - something all these American "allies" are keen to achieve.

The Chinese aerospace environment has been carefully nurtured and designed to provide a robust industrial base along with healthy competition. Unfortunately the progenitors of the Indian Republic decided to hide behind slogans and rhetoric rather than behind tangible firepower. As Mao is so often quoted as saying "Political power flows out of the barrel of the gun", so does national power it would seem .

[SaiK]

there is nothing lca++ platform modification would not provide that needs a special amca venture. just keep improving on lca versions itself the right way to reach amca. add a twin engined lca-3, and see where we land.

[NRao]

The AMCA project in contrast is FAR more ambitious (at least on paper) to what they have done so far and it will require them to dig deep to deliver.

++.

A quantum leap in technologies. No way the LCA can contribute in most respects. Just no way.

On digging deep - I think they had started work on many technologies some time back.

The key will be FBL. There is only one plane that is FBL - a civilian. The entire hardware would have to be new - nothing common with the LCA. That by itself is challenging.

[neerajb]

Gas turbines used for aircraft propulsion are not the same as those used for shaft power production. You'd have to carry out some serious modifications to a jet engine to be able to do that and the cost may very well outweigh the benefits.

You started with this which is incorrect.

The turbines of a jet engine are meant to produce just enough shaft power to run the compressor whereas ground based GT's are designed to power both the compressor and the auxiliaries. One cannot simply extend the shaft of a jet engine and connect it to an electric generator. Even if you were to you'd never get optimal fuel efficiencies because that would not be the design point.
A separate power turbine behind the nozzle would be a minimum and that is not a minor modification

Then you said this which is obvious.

The casing even doesn't have to be of the same radius.

They have to be of the same radius. If you expand the casing diameter you lose the Ke of the flow (like a diffuser) and turbines make use of the flow kinetic energy..

And no, not 'just an addon' like a new cover for your mobile phone. Will you be willing to design and build a power turbine for an gas generator whose useful life is close to an end? Is it worth all the effort?

Again, Im not saying its impossible, but just not worth it.

Yes it's an add on and there is no other major difference between J79 and LM1500 other than the power turbine section which is available commercially from multiple sources. Moreover yes the power turbine is bigger than the general duct. I do agree with your last time that a new power turbine will have to be developed if a MiG-21 engine is to be used for power generation but it is not that big deal as you make it out to be. Generally industrial GTs are derivatives of aircraft engines like J79/LM1500, CF6/LM2500.

Cheers....

[Singha]

^ I dont see why you are so hung up on FBL. even pulleys and wires will work inside a 5th gen VLO fighter if used properly..a means to an end...we are not trying to achieve anything huge with FBL other than a few weight savings (at the cost of more headaches with new relatively uncommon stuff).

the biggest challenges are
- getting the shape & size right and mating it to right engine for performance
- getting in enough of internal fuel and volume of internal bay to make a useful product
- meeting IAF reqs of airborne performance
- engine
- radar
- self protection spherical suite and side scanning radars
- materials techs for all the above
- reliable production of all these new stuff
- tools and machines for all this production
- meeting timelines
- flight test program

[SaiK]

Getting to FBL is nothing more than replace the 1553 wires with fiber for 1773, get the adaptors and connectors at the bare minimum.. and then, if you want to get exotic, then make the actuators and sensors interact with dedicated embedded sytems (if they are not already done it), and only send only the control signals from cockpit. i would do that. just an example say for the fligth control surfaces.

^add to the above:
passive tracking and scanning - vital for stealth.

e.g: twin engine LCA:

[NRao]

even pulleys and wires will work inside a 5th gen VLO fighter

Absolutely !!!

The question was related to what from the LCA can be carried over to the AMCA.

However,:
1) Is that what is proposed for the AMCA? I have not been keeping up with this project, but, the last time I check it was FBL. For better or worse that is what it is - as far as I know. So, that is my reason for being "hung up"
2) IF FBL is still the proposed technology, then, my contention is, that pretty much nothing from the LCA can be reused in the AMCA. As a stopgap measure, perhaps yes. But as a one-to-one transfer, no. They will need a better everything - radar, engine, etc. It is really no use having a super sensitive set of surface controls and a 10 year old engine (a predicament that the PAK-FA seems to be in - super body/design, but waiting for a compatible engine, till then making do with an older engine)

Yes, replacing wire with a different 4 digit number (that I do not understand), actuators, etc is understood. But so will the computers, other hardware, all software, sensors, radar, etc, etc, etc.

Or, of course, they can use everything from the LCA and run the FBL at a much (much) slower speed.

And, from what I have seen the AMCA seems to me further along than where the LCA was at the same point in time. And, the design - to me - is very, very different.

Thanks.

[ArmenT]

^ I dont see why you are so hung up on FBL. even pulleys and wires will work inside a 5th gen VLO fighter if used properly.

On an inherently unstable aircraft? Really? Just curious.

[SaiK]

wires are good enough to get the response. why are you curious? 1553 bus i guess can go upto 20 mbps.

what is the architecture in your thoughts?

btw, arment.. singha means bombing missions for pulleys. good enough, rather say high speed chase and dogfights.

[ArmenT]

^^^^
Oh, I thought he was saying that the control surfaces would be driven by pulleys and wires (and wires not used to convey electrical signals either). My mistake. Thanks for clarifying.

[SaiK]

perhaps you are the right person to start BR idioms similar to dictionary.

[nits]

Hmmm...have been reading the LCA forum everyday after Avinash Chander's high profile LCA commitments/Bangalore visits last month but zero updates on the LCA progress, especially on the leaking radome, AoA limits extension and the series production hiccups at HAL.

Other than updates on number of flights, there is really no progress on the LCA front. Same for the IJT. Disappointing, to say the least.

No one goes on a Long Drive on LCA just because weather of Banglore is awesome... Increased # of flights means they are testing \ fine tuning more parameters and work is in full swing to achieve IOC 2

[suryag]

another mig crashed - pilot died

[Singha]

I meant if the wires and pulleys connecting the cockpit stick and pedals to the control surfaces can act quickly enought to match FBW actuators why not? plus they are inherently VLO being made of wood and jute fibers.
all these are means to an end , not the end itself.

what is the huge advantage of FBL over FBW that we must adopt increased risk on top of a raft of other risks?

the pakfa and f22 seem to fly ok with FBW.

northrop grumann and LM have classified facilities both indoor and outdoor in the SW deserts of mongolia where subscale to full scale models of flying machines can be subjected to all manner of radar and IR detection and reflection under controlled conditions with nothing nearby to disturb the pristine EM env.....these are infra challenges we need to close gaps on more than FBW imo(components from moog types are available..its not considered a sensitive product).
we have no proven track record in IR suppression of exhaust plumes or in 2D flat nozzles. panda stole the first for longsword for a PIO engineer based in hawaii.

[Lalmohan]

by moving to FBL, you can achieve greater weight savings and more redundancy in distributing your controls around the a/c
analogue wire and pulley is made redundant/inefficient by FCS to actuator digital controls - if you're using an FCS then translating that to a mechanical signal to the wire and then having the hydraulics around to power it - are less efficient than electronically sending the control instruction to an actuator at the control surface itself - which may or may not require hydraulics to move it

[SaiK]

stats please: what is the weight gained? just guesstimate.

BTW:
regarding wire: we are talking the wire that is existing in LCA now. I am pretty possitve it is 1553 based bus, not a wire and pulley should be viewed under an idiom rather than anything else.

still, the feedback control loop should embedded within the system that is "sandwiched" part of the actuator assembly for all things considered.. and the joysticks to actuators are simple codes that sends the position of the control rather anything else. the feed back signals will be again not sent via wire here.

i am sure, they will cover redundancy of the electronics.. and complete SoC chips as redundant systems.. these are dedicated dim-a-dozen value now-a-days.

So, there is not much other health data, and control signals reaching over the fiber. all depends on the architecture. how much of the federated mission computer needs info, etc.

[Lalmohan]

saik - you appear to be confused

1. wire and pulley is the traditional mechanical way of controlling aircraft (wire means steel wire bearing a mechanical load)

2. fly by wire = databus connecting flight control system (computer) to the actuators on each control. i cannot remember if 1553 is used for this purpose or for general data flow around the aircraft's numerous other systems

3. fly by light = use fibre optic cable instead of copper wire databus as 2; same flight control system, but digital to light converters and vice versa. you save weight by replacing databus with optical cable, but may lose it in the converters

you might also get higher clock speeds on the FBL system, potentially allowing for 'smoother' control law application to the actuators

[SaiK]

we are corroborating same here (tomato/tamoto). LCA is not on wire and pulley is what I am saying..

you have to track back to discussions, that we dont need fbl for LCA++ on the higher priority is what we are saying. The data sent on these lines is very minimal within the existing architecture.

but if at all, fbl is what we have to prioritize, none other than LCA TD platform helps to get that going parallel. concurrent tasks can begin.. but we are ignoring that is important to schedule, and find the critical path for the project done in time.

engines and kaveri takes very much the core. we need that kaveri-9 on the TD and test out the parameters. we can't just ignore it.. this is a national shame if we do that. we are not that dumb to accept what is tested out success in russia, can't be put on the platform.

priority one: get that k9 on board lca platform. should have done last year.

[vipins]

According to this CSIO annual report PDF FBL was under development at that time as per point 37 of ongoing projects

37 Dev. of Fly-By-Light Tail Rotor Control System for Advanced Light Helicopter (ALH)

And this 2002 tribune article mentions that FBL for Dhruv was developed at CSIO.

link

Chandigarh, December 22
A hi-tech fly-by-light (FBL) system for the Advance Light Helicopter (ALH) has been developed by the Central Scientific Instruments Organisation (CSIO) here. A team of scientists left for Bangalore this week to install the system in the aircraft for trials.

The FBL is used for sending signals from the cockpit to various instruments and sub-systems which control flight parameters of an aircraft. The ALH, developed indigenously by the Defence Research and Development Organisation, is undergoing user trials with the IAF and the Navy. All three services will have their own versions.

Sources told TNS that the project, initiated last year, was completed some time ago, but non-availability of an ALH had held up trials. The system will enter production once it is cleared and an indigenously produced unit is expected to cost as little as Rs 50,000-60,000, a top CSIO official said. The system would also be modified to be installed in other choppers in service with the forces, including the Chetak and the Mil series.

The FBL system is a further development of the now commonly used fly-by-wire (FBW) system. While signals are transmitted through electrical impulses to various control surfaces from the cockpit in an FBW system, the same is done through light impulses passed via Optical Fibre Cables (OFC) in the FBL system. Prior to the development of these two systems, the controls were operated mechanically.

The ALH will be the first Indian aircraft to be equipped with the fly-by-light system. Even the Light Combat Aircraft (LCA), which made its maiden flight earlier this year, is equipped with a fly-by-wire system. While the technology was earlier restricted to combat aircraft, now civilian airliners, specially the Airbus series, also incorporate the Fly-by-Wire system.

The use of optical fibre cables, instead of copper wires, gives the FBL system several advantages over the FBW system. Besides being considerably lighter and cheaper, the FBL systems had the capacity of transmitting a greater number of signals and data simultaneously. Moreover, optical fibre cables are immune to electro-magnetic interference or electrical conduction and result in better gyro control of an aircraft.

As far as the working principle of the system is concerned, experts say that in FBL systems, signals from the cockpit are converted into light impulses and focussed on the control surface concerned. Control signals between the pilot stations, flight control computer and actuators for rotor blade controls are not transmitted electrically, via wire, but optically, via hair-thin optical glass fibres.

[Singha]

The short distance within a plane can be easily spanned by short range cheaper optics but eventually electrical conversion has to take place at both ends, so one loses one of main advantage of optical fiber which is relatively error free over long distances and lightweight cable. Secondly the vast data capacity of coloured dwdm optics to multiplex wavelengths onto long distance fiber is not needed inside a plan as you wont be needing 100s of gbps for fcs or sensor fusion.

To me fbl looks like a solution looking for a problem.

[NRao]

Unless something has changed in the past year or so, AMCA is FBL. As far as my recollection goes they have conducted substantial research. That has got to mean designing, manufacturing and testing all sorts of gizmos. IIRC they had planned on distributed computing too - localized decision making with central coordination. Conformal sensors, etc, etc, etc. Things that cannot even exist on the LCA IMHO.

Going back should mean consciously tossing the baby with the bath water. A topic for the AMCA thread.

[Lalmohan]

IIRC FBL is also EMP resistant?

[Katare]

^ I dont see why you are so hung up on FBL. even pulleys and wires will work inside a 5th gen VLO fighter if used properly.

On an inherently unstable aircraft? Really? Just curious.

Yes! What's the big deal in unstable AC that needs FBL?

It'll be at the bottom of the list of priorities for AMCA or anyother 5th gen aircraft.

[SaiK]

IIRC FBL is also EMP resistant?

true.. but redundancy needs big time planning.. i am thinking at least 4 to 8 backup fiber lines, that seemlessly plays in, and each of these have separate circuitry integrated with control system. I am currently only discounting the weight of the copper/gold plated wires. optical to electronic signals to electrical(or hydraulic) actuators circuitry will remain.

btw, the only other enemy to light is light.

[jaladipc]

IIRC FBL is also EMP resistant?

It is still vulnerable based on the grade of electronics used for conversion such a lasers/LED for emission and photo-diodes for receivers.

The main disadvantage is the flexibility and loss of reflexion at deep bends. OF`s cant be routed like conventional wiring.Not to mention the maintenance issue.I bet a multi-mode fibre can get ride of a huge stack of conventional wiring that only does data transfer.

With the new strides in photo-detectors, especially the multi-layered avalanche type reached conversion efficiencies of ~60% which means, betting big on data cum electricity transfer

But the added advantage is, using the same fiber as smart skins. Means when there is a relative stress applied on the fiber, the change in angle of reflexion and wavelength can be corresponded to the stress occurred at a specific point on the body of the aircraft

Edited Later: Not to forget the awesome cockpit illumination

[SaiK]

fiber skins !? not mecahnically feasible for aircrafts. i don't know jumping to fiber itself a good money well spent now. there are ton of other things to focus and get lca-mk2 going. btw, nothing stopping from researching though. we have the lca platform -- our own. none can deny tech transfer here. neither the french and khans nor the russkies. see the freedom! this is what we get. now imagine doing that on a pak-fa frame? before even they demo, they have jacked up the prices.

apologies to those firang men and middle agents for this post. unfortunately, we have classified ourselves as seekers than givers. unless that threshold is crossed, this subduing attitude will continue. the more they delay lca FoC, the more is the fraction that happens against going amca.

[RKumar]

Flight update

From
LCA-Tejas has completed 2265 Test Flights Successfully. (09-July-2013).
(TD1-233,TD2-305,PV1-242,PV2-222,PV3-366,LSP1-74,LSP2-275,PV5-36,LSP3-154,LSP4-90,LSP5-196,LSP7-51,NP1-4,LSP8-17)

To
LCA-Tejas has completed 2270 Test Flights Successfully. (15-July-2013).
(TD1-233,TD2-305,PV1-242,PV2-222,PV3-366,LSP1-74,LSP2-275,PV5-36,LSP3-155,LSP4-90,LSP5-198,LSP7-51,NP1-4,LSP8-19)

[NRao]

The fact that they have pretty much shut down the AMCA program and moved most, if not everyone, to the LCA MK-I certification effort shows where their newly formed focus is - so that topic should be laid to rest.

WRT MK-II, I hope the MK-I effort would provide some momentum and at least that effort does not lean on the AMCA group (too much?).

While the LCA program is very, very important (from maintaining squadron strength), so is the AMCA (from technology).

The issue - as I see it - is testing. It is not designing, fabricating, manufacturing, producing, re-engineering, etc. India has no real data points when it comes to testing. The LCA being the very first product that they have jumped into. And throwing bodies at testing will NOT solve the problems. Nor will a Mantri demanding that the IOC be brought in in time. Nor will posters expectations. That is all childish and silly. Even mega vendors fail when they bring out new products (AL-50I or Boeing Dreamliner issues). It does not help matters when there is no one willing to share testing data (which is why the FGFA was so important).

I think, seriously, that the IAF should accept a rolling IOC/FOC (something they have done when it comes to foreign efforts - MKI in particular). IF the MoD + IAF (and others) are going to insist on a hard date for IOC/FOC, the LCA (and perhaps even the AMCA) are doomed to fail. Sadly something we seem to be witnessing WRT the Arjun. Heck even the likes of Toyota have recalls with years of experience under their belt.

Testing a product for the first time takes time - and constant failures are normal. Testing a complex system like the LCA for the first time is even more time consuming. That does not even include the fact that the LCA has to be tested under the lowest of risks - no crashes, no fires, no failures of any kind. Bailgaddis fail folks.