AMCA News and Discussions

[abhik]

Compensating for lack of precision for warhead weight is a prohibitively expensive proposition because of the non linear relationship between the explosive yield and the radius of destruction. The blast wave would dissipate by a factor of ^3 of distance(or so). One can see this in action in this charthttp://s1116.photobucket.com/user/benne ... ort=3&o=60 (showing the relationship between yields of nuclear weapons and their destructive power) which was linked earlier elsewhere. So a doubling of explosive power will result in an increase in destructive radius of only 20-25% and 10x increase will result in the destructive radius by a little more than 2x.

[NRao]

Compensating for lack of precision for warhead weight is a prohibitively expensive proposition because of the non linear relationship between the explosive yield and the radius of destruction. The blast wave would dissipate by a factor of ^3 of distance(or so). One can see this in action in this charthttp://s1116.photobucket.com/user/benne ... ort=3&o=60 (showing the relationship between yields of nuclear weapons and their destructive power) which was linked earlier elsewhere. So a doubling of explosive power will result in an increase in destructive radius of only 20-25% and 10x increase will result in the destructive radius by a little more than 2x.

Those are some of the basic factors that any MIC will have to deal with. Physics cannot be overcome by politics or anything else.

The question is is it worth the while to overcome, from a weapons point of view, such problems. Does any of teh services have a dire need for some product like that and what is teh cost associated with overcoming the physics.

A few years ago, I recall, the story of Nag. There were people rather skeptical about that missile - we have no sensors, we have no this and no that. I really have not paid close attention to it in the past few years, but I suspect it is doing rather well. Only because of people (scientists and politicians and others) who kept at it. Perhaps there is more to improve, but that is teh game one has to play. One cannot be concerned with people who laugh or post smilies - such people have no meaning or existence.

Sorry. OT, but ...........

[Viv S]

I think it should not be forgotten that the American SD(S)B is a glide weapon that has standoff ranges that are advertised as about 100 km. That would mean a waiting period of 10 minutes between designation of target, launch and hitting the target. This may be fine for a truck on an Afghan or Pakhtunkhwa road but totally useless for moving vehicles in an evolving battle scenario. Plus 9 kg explosive may be good for vehicles and hangars but it won't even take out a decent sized bridge despite the kinetic energy. Forget about runways.

The SDB II will take out any moving vehicle or radar with ease. For static targets, the SDB-I packs a 95 kg warhead. With a hardened casing to punch into fortified targets. The L-SDB should also pack a fairly heavy warhead.

[brar_w]

For time-critical moving targets they aren't going to launch a weapon at 40 nautical miles..The best way is to get to the area faster and that means getting closer to the target at launch. The SDB III will most likely feature some sort of propulsion particularly if the Spear requirements are merged (Britain buys an interim SDBII and co-develops an SDBIII with Raytheon and the USAF that may have some sort of use for it for time critical CAS). Despite that, a tank, truck, or other vehicles are going to find it tough to outrun a munition launched from a high subsonic, or supersonic fighter and gliding to target especially if they don't know they are being targeted.

The maximum range at altitude would be used for shots at fixed, or slow moving targets such as radar sites that need a while to get mobile. This is true for any glide munition regardless if it is 250 pounds, 500 pounds or 1000 pounds.

[Austin]

^^^
If Vayu Shakti are anything to go by, the IAF typically uses 1000lb in dive mode or CCIP for individual targets, like aircraft shelters. 250kg and 100kg are carried in multi-carriage and used for attacking an area, such as railway yards. PGMs (typically 1000lb LGB while other AGMs hardly seen) are few and so are used judiciously for high value targets.

So a 150-200 kg warhead would suffice for say 60 % target, while we need guidance that gives CEP of 5-10m without relying on external sensors need cheap INS plus EO guidance for terminal homing , if the aircraft navigation and sar are good it would boost accuracy of Indian 150-200 kg glide bomb

DRDO has multiple sensor/guidance hardware but many are for high end missile relying on cheap reliability of satellite aided navigation is not good as they can be denied or jammed

[srai]

Youtube: CAS Press Conference – Air Force Day 2015
Listen from this point for couple of minutes.

As per CAS Raha, AMCA is the Indian FGFA. Plan is to work on it for the next 15-years and will be the replacement for existing MRCA types in service like MiG-29 and Mirage-2000.

[SaiK]

How do these guys know GTRE Kaveri K-10 will be the one powering the AMCA?

http://thediplomat.com/2015/12/who-will ... hter-race/

India

The final major indigenously developed Asian fifth-generation fighter is India’s Advanced Medium Combat Aircraft (AMCA), currently under development by Hindustan Aeronautics Limited. As opposed to Japan and South Korea (and China, if the espionage reports are accurate), India doesn’t currently and likely won’t in the future have access to the F-35’s technology. Furthermore, as part of Prime Minister Narendra Modi’s “Make in India” campaign, much of the technology and hardware installed in the AMCA will be indigenously developed. However, there are speculations that HAL will be able to acquire some of the necessary technology from Russia, which is in the testing stages of its own fifth-generation fighter, the Sukhoi PAK-FA T-50.

The AMCA is supposed to supplement, rather than outright replace, many of India’s current platforms. Like the F-35, the AMCA is supposed to be a multirole fighter, able to conduct both air-to-air combat and air-to-ground sorties. It will be powered by twin GTRE K-10 turbofans, the successor of the cancelled Kaveri engine. This will be designed and produced with help from a undecided foreign company (the odds are that this will either be the French Snecma M88 or U.S. General Electric’s F-414.) HAL is planning to design a carrier-based platform of the AMCA as well. These would probably operate from the new Vikrant-class aircraft carrier. According to the Times of India, the AMCA will be ready for testing in 2023-2024.

The next-generation battle for Asia’s skies is on. Which of these birds will prevail over the continent?

[SaiK]

sorry, to up the ante, I need to put this OT link

http://sputniknews.com/military/2016011 ... ement.html
Formidable Boost: China to Produce Cutting-Edge Aircraft

[NRao]

What and where is this?

[brar_w]

What and where is this?

Thats BaE's replica or its offshoot.

[JTull]

Seems fake. Those guys don't look like SDRE types. And that white van and the high viz jackets for everyone is so western!

[shiv]

What and where is this?

Dull, cold, grey day. Lemon green hi-visibility jackets, R hand drive van. Britain

[Cosmo_R]

^^^ Low (very) speed taxiing trials. Upside down.

[SaiK]

perhaps x2 can join us. modiji can wave his wand.
http://www.upi.com/Business_News/Securi ... 453994994/

[brar_w]

^^^ Low (very) speed taxiing trials. Upside down.

Pole testing..

[PratikDas]

^^^ Low (very) speed taxiing trials. Upside down.

Pole testing..

Speaking of which, could someone please tell me how they test aircraft for stealth, which I presume involves aiming radar-like transmissions at the aircraft on the pole, when the aircraft is mounted on a huge metal pillar that is sure to bounce every kind of electromagnetic signal?

[Indranil]

You now the pillars signature.

[PratikDas]

You now the pillars signature.

Right, but due to atmospheric fading the response will not be so exact as to allow a complete cancellation. Then there is the issue of dynamic range. Even after the best cancellation, the remnant signal from the pillar may not be so miniscule/quiet that you can accurately profile an aircraft whose radar signature is compared to that of a golf ball. Receiver blocking and/or the dynamic range of measurement instruments would become the bottleneck.

[member_26622]

Here is the correct picture to test stealth characteristics....

[PratikDas]

Exactly, nik, I've seen that picture before. This begs the question, what was the ultra-modern F-35 doing inverted on that hunk of a pillar anyway?

[Cosmo_R]

^^^ Low (very) speed taxiing trials. Upside down.

Pole testing..

Joking

[brar_w]

Exactly, nik, I've seen that picture before. This begs the question, what was the ultra-modern F-35 doing inverted on that hunk of a pillar anyway?

It was the HALO model developed for lockheed by a third party and not the F-35. They were probably validating its signature from the bottom or were trying to narrow down some testing requirements and models right before the actual design was sent off to the lockheed facility for more thorough RCS testing much later in the process. There was also a picture of the X-35 doing the rounds on a similar pole back in the day. Since Lockheed is the most experienced RCS tester in the world (they did RCS testing for most of the stealth designs initially, and supplied RCS test equipment and poles to even northrop and boeing) one would imagine there is a perfectly good explanation for this. There is an indoor test facility at Fort Worth (factory) and Cameri Italy where each F-35 has its signature validated prior to delivery (second picture). A similar one would also be made in Japan.





http://thehowlandcompany.com/radar_stea ... d_F-35.htm

I have posted this before, but its worth mentioning here since it gives a good summary into Lockheed Martin's company owned RCS facilities -

http://www.otherhand.org/home-page/area ... -facility/

[PratikDas]

Thanks, brar_w! That first image of the inverted F-35 with the vast grey expanse is ridiculously impressive - like something straight out of Independence Day or Men in Black.

[member_29267]

Although not quite related to AMCA, Japan unveiled a downscaled prototype of its 5th gen aircraft.

Japan unveils first homegrown stealth fighter prototype

[member_22539]

^Notice how they painted it quite SDRE instead of the TFTA "Fifty shades of Gray" F35/Han copy, etc.

[member_29190]

All these 5gen jets been produced makes me think. No right angles, no engine blade expose and internal bay and you get a stealth jet!

Any country with decent RCS test facility, having a history of build a fighter jet and able to structally copy a F-22/ F-35 can build a low observable jet?

So what's so great about building one.

[brar_w]

With stealth, shaping is only a part of the deal. Not only do you have to shape the aircraft to be low-observable, but you also have to use low-observable materials, RAM and once you do that you have to then go back and do the same while still meeting performance, range, payload, weapons carriage, and sensor requirements. Throw in Supercruise, and your material choices and shape are affected. Throw in long range, and again you have to optimize differently.

Essentially, each trade you make in favor of a lower RCS, affects the other metrics, so the first thing to do is understand these things so that an optimized design can be created. This is where decades of testing various shapes in the tunnel, advanced prototyping etc come in. If you take Boeing for example, they would have flown at-least 3-4 small scale tech demonstrators (X-36 and BoP among others), prototypes before they build a single full scale tech. demonstrator for the 6th generation F-X or FA-XX fighter. This doesn't count countless models and configurations they must have tested in the tunnel or on the polel.

All in all plenty of conflicting priorities must be juggled and RCS targets met despite of that. This is before one gets into avionics and electronic systems for low-observable aircraft. These have been a focus of research for well over 3 decades now. Absolutely, no point in designing a hard to detect shape, only to give yourself up by other means (IR or passive RF). The design conflicts have been described elsewhere as the RCS guy wanting a B-2, the fighter jock wanting an F-16, the Bomber jock wanting an F-111 and the sensor guy wanting an E-3 . Once you have all these things in place, then there is a huge problem of integration and as the F-22, and F-35 program's have shown, integration has been as challenging as actually developing these systems. In fact developing the systems and technologies may have in certain cases been much easier.

It will be impossible for anyone to articulate how tough these things are in a forum post. Best to read up on the work of folks that have done this. The book linked below is one of the best for such a description. I have referenced it on several occasions here and it is a must have for those that are really looking to see what lies ahead of the AMCA and what capability the Indian MIC will have by the time the AMCA is ready and deployed.

http://www.amazon.com/Advanced-Tactical ... al+fighter

[member_22605]

DL jodhpur has a very good near field rcs test facility which has great facilities to convert it into near accurate far field values.and it has been in use for almost a decade.
The real complexity with stealthy aircrafts is the intake which causes massive SBR returns and the rivets which glow up. Managing specular reflections and diffraction is done easily by most people these days. The USA is ahead in addressing these issues and their RAM/RAS and production quality control is probably very good. Btw the ridiculous rcs numbers of 0.001m2 etc are accoreing to me and most EM tools, only for the airframe i.e. not including returns from the rivets, intake etc, else getting almost -40db is almost impossible and this is where the Russians are frank with their numbers and an rcs value of around 0.1 to 0.5 is what the f35 and f22 would manage in the real world. Also these numbers are mostly not mentioned with the frequency and fov and again my feeling is that the lm numbers are all in 2 to 12Ghz range while we Indians and Russians are interested in 1 to 18Ghz and managing the low freqs is extremely difficult.
Here i would want to stress that f22 despite what lm and usaf claims, must have a lower rcs than the f35 and no amount of serration or dsi can compete with a square exhaust and serpentine intakes. Again all this is from the little study that i have done and i may be off the mark.
Cheers!

[brar_w]

DL jodhpur has a very good near field rcs test facility which has great facilities to convert it into near accurate far field values.and it has been in use for almost a decade.
The real complexity with stealthy aircrafts is the intake which causes massive SBR returns and the rivets which glow up. Managing specular reflections and diffraction is done easily by most people these days. The USA is ahead in addressing these issues and their RAM/RAS and production quality control is probably very good. Btw the ridiculous rcs numbers of 0.001m2 etc are accoreing to me and most EM tools, only for the airframe i.e. not including returns from the rivets, intake etc, else getting almost -40db is almost impossible and this is where the Russians are frank with their numbers and an rcs value of around 0.1 to 0.5 is what the f35 and f22 would manage in the real world. Also these numbers are mostly not mentioned with the frequency and fov and again my feeling is that the lm numbers are all in 2 to 12Ghz range while we Indians and Russians are interested in 1 to 18Ghz and managing the low freqs is extremely difficult. The more and more an adversary is reliant on lower-frequency sensors, the easier it is to not only trick those sensors and confuse the SA picture but also to counter them through various other means. No one is going to be able to jam their way through an enemy that has extensive sensor coverage covering the VHF through to
Here i would want to stress that f22 despite what lm and usaf claims, must have a lower rcs than the f35 and no amount of serration or dsi can compete with a square exhaust and serpentine intakes. Again all this is from the little study that i have done and i may be off the mark.
Cheers!

# The USAF or LM have not provided confirmed RCS numbers for any of their aircraft. Those have been estimates based on reporters that have been fishing for them on their own

# The frequency range discussion has also not been a factor, since these numbers are not openly discussed. Here we know that certain aircraft are designed at breaking fire-control kill chains while using stand-off tactics against much lower-frequency sensors while others have been designed for a much broader range of RCS targets and emitter threats. Horses for courses, a fighter fights other fighters and uses speed, maneuverability and its weapons suite in a different way to a bomber or a strike UCAV. A strike fighter in the USAF also performs a subset of the overall strike mission since the mission is spread over larger manned bombers, other stand-off strike figthers, and UCAV's.

One of the biggest advantages of RF stealth has been to deny an adversary the effective tactical superiority in the 2-12 Ghz frequency range and force greater and greater investments towards lower frequency sensors and the SA obtained through them. This in turn has an effect on sensor size, weight, quality of data and cost and opens up a lot of opportunities for targeting this SA picture both through EA/EW and through kinetic options. Prior to this the B-2's, F117's and perhaps a few stealthy cruise missiles could only deny these sensors over a small tactical battle-space and for a limited conventional conflict (given fleet sizes). With the F-22, and F-35 this essentially scales this capability up to the majority of the fleet even if it is more geared towards a narrower frequency range compared to the B-2.

# I wouldn't trust Russsian numbers on US aircraft just as I wouldn't trust US number estimates on Russian aircraft unless those were aircraft or systems the US had extensively tested (Such as the various mig's over they ears or the Su-27).

# The F-22 and F-35 RCS can only be known by LM or the USAF among others with a need to know. It is entirely possible that some angles the F-35 is stealthier while the F-22 has better all aspect RCS reduction. Material technology has also advanced to a point, where effective RCS i.e. the RCS on any given day is better on the F-35 since it relies on much less patchwork and coating monitoring in favor of its FiberMat approach. This is before we get into any active stealth features on both aircraft. That the F-35 had a lower RCS to the F-22 was claimed by the man in charge of all fighter combat aircraft in the United States air-force and was neither confirmed, nor denied by LM.

[JTull]

You forgot to mention engine and the super-cruise, AFAIK, the main sticking point on FGFA.

[brar_w]

You forgot to mention engine and the super-cruise, AFAIK, the main sticking point on FGFA.

Yes that issue is there as well since we are now seeing a move from 5th generation propulsion technologies and materials to sixth generation ones with far more conflicting requirements leading to adaptive engine technology being funded by huge amounts. Propulsion is the single most important enabler of advanced combat aircraft.

[member_28397]

^Notice how they painted it quite SDRE instead of the TFTA "Fifty shades of Gray" F35/Han copy, etc.

Japanese Flag?

[NRao]

^Notice how they painted it quite SDRE instead of the TFTA "Fifty shades of Gray" F35/Han copy, etc.

That plane, in particular, is a tech demo, meant to test/validate almost all their proposed techs. The final plane will make it to teh drawing board after they get some results from this.

[brar_w]

This is a scaled technology demonstrator. Its not even the size they eventually want to be at, nor does it include the new engines that they have just started working on. An excellent way to de-risk some of the technologies particularly TVC and the controls. Most tech demonstrators aren't painted in military schemes unless the point is to test/validate a particular visual scheme to enhance stealth (BoP did that) or if the tech demonstrator is more like a prototype with a particular service embedded in the process.

[SaiK]

nit, ayyoooo it is so easy to produce stealth jet if we can make the skins totally permeable!

howdy kevlar! shape science is an internal bijnej. give me a bunch of good aero-engineers, and I will create one on the fly

[member_26622]

By the way the pic I posted was for F117 testing, very likely 20 years old!

Here is what pisses me off big time about our dumbness -

China - Develops 2 stealth planes on its own, rumors of stealing F-35 blueprints, spends all $$$ on indigenous efforts
Japan - Develops 1 stealth plane after buying limited F-35 copies (likely got access to working prototypes to build know how), Spends $$$ on indigenous efforts

India - total Jumritalia approach - straight out of a sick comedy show >> Donate 8 billion $ to Russia and 100% repeat of Gorkshov stinker, Wants to buy 4.5 gen Rafale from France to make into what god knows, runs Desi AMCA program on pittance $ budget. All of this idiot like dance for getting where?

Why don't we just buy a working stealth jet F-35 (or 30 copies), learn and adapt key aspects into AMCA. Isn't this the lowest risk and costly approach? Hard fact is US has the most knowledge and experience in stealth like 2 decades more than nearest competitor China. Russia, Japan and France are all history in terms of 5+ gen Aviation capabilities.

[Gyan]

That is why I think a lot of persons on BRF are recommending that we buy only LCA and Su-30MKI while spending money on UCAV, AMCA, LCA MK-3 rather than frittering it away on FGFA and Rafale.

[member_29294]

^

The problem is that there is such obvious tensions between HAL and IAF, where IAF blames HAL for all their failings. IAF just wants to cut them out of the picture at this point, hence their obsession with buying phoreign maal and stalling indigenous development at HAL.

For example, IAF Air Chief will make statements such as "There is no Plan B for Rafale", directly undermining MoD position during negotiations that were and are still ongoing. http://www.spsshownews.com/news/?id=172 ... -IAF-Chief

Old Scamgressi government also liked to keep low transparency in the military establishment to keep their corrupt kickback deals a secret, Scamgressis might have gotten voted out but it will be years before all their moles and foreign agents are routed out of the military. MMRCA was conducted under their watch, and you can bet there must have been substantial kickbacks involved. Who knows how many people have already gotten paid under the table by Dassault to support this deal.

IAF and military as a whole needs a lot of in-house cleaning and anti-corruption measures to be taken, otherwise Tejas and Arjun story will continue to repeat itself.

[member_26622]

For saving 8 billion $$$, I am willing to have ISRO send IAF and HAL to deep space - oblivion. India does not need this bullshit infighting, otherwise we will have another foreign flag flying from Rajpath in a matter of time (lessons from History should not be forgotten)

Millions of Indians over 10+ generations gave up their lives to free us from 1000 years of slavery. HAL and IAF have no business to put our freedom at risk.

India needs 1000 plus fighters at reasonable cost to deter any aggression. Our economy is a quarter of China, so need to use our money wisely.

[Gyan]

Can BRF generate a list of leading Empires in the history of Mankind which depended on "imported arms"? My list = NIL.

Paying some other Nation to do research on your behalf is height of absurdity. A JV means that India should contribute "in kind" by doing research of components that fall to India's share in Indian Labs with Indian Scientists and Engineers.

PAKFA R&D contract is of USD 4 Billion with Rafale coming near USD 10 Billion (give or take a couple). Why not spend USD 5 Billion on 200 LCA, USD 3.5 Billion on 50 Su-30MKI and Balance USD 5.5 Billion on aggressively pursuing AMCA, LCA Mark-3, UCAV, turbine engines etc.