Airborne Early Warning & Control: News & Discussion

Karan M · Post by **Karan M** » 02 Sep 2014 21:47

An AEW&C which can look out to 300 km and will be detected on RWR at similar if not more ranges, and will be escorted by a flight of dedicated fighters, needs to think about paint on its vital sensors because they "stick out". Brilliant.

srin · Post by **srin** » 02 Sep 2014 22:02

While we're looking to develop the bigger DRDO AWACS, I hope we buy around half a dozen more of these birds and not stop at just 3

member_23370 · Post by **member_23370** » 02 Sep 2014 22:55

The range is 300 km just like the displacement of P-28 was 2500 tonnes.

. I seriously hope they order at least 3-6 more to make up the numbers while developing the bigger AWACS.

RoyG · Post by **RoyG** » 03 Sep 2014 00:15

indranilroy wrote:There is reason why they are not painted.

what is the reason?

RoyG · Post by **RoyG** » 03 Sep 2014 00:18

Karan M wrote:An AEW&C which can look out to 300 km and will be detected on RWR at similar if not more ranges, and will be escorted by a flight of dedicated fighters, needs to think about paint on its vital sensors because they "stick out". Brilliant.

No need to draw down the pom pom's Karanji. I'm not knocking it's specs.

Indranil · Post by **Indranil** » 03 Sep 2014 02:52

RoyG wrote:
indranilroy wrote:There is reason why they are not painted.
what is the reason?

The black colour is because of the anti-erosion coating put on the fiberglass. Beyond this an outer coating of paint matching the aircraft colour can be used. However, this has to be done very carefully as the performance of the radar can degrade appreciably if the paint is too thick or if the application is uneven. Then once the plane is in the field, the paint degrades due to exposure to sun and rain, and abrasions due to sand blasting in flight. This leads to cracks/chips/pinholes, which along with the moisture contained in them degrades the performance greatly. In some cases, the performance was found to degrade to almost 50% (in civilian aircrafts). The normal desired performance of the radome is above 90% (recommended for civilian aircraft). So when the performance falls below this threshold, the paint has to be carefully removed and the radome has to be repainted. This is why with most military hardware (where aesthetics don't matter), you would find most radomes to be black, i.e. only with the anti-erosion coating. This becomes all the more important if the aircraft is going to be fielded in desert conditions. (Please read about what the US found with their aircrafts fielded in Afghanistan).

There was also a talk (in AI'13?) on AEW&C, how the dielectric performance and placement of arms holding up the antenna affect the overall performance of the antenna itself.

RoyG · Post by **RoyG** » 03 Sep 2014 04:10

Interesting. Thank you for the explanation.

Leo.Davidson · Post by **Leo.Davidson** » 03 Sep 2014 05:08

indranilroy wrote: The black colour is because of the anti-erosion coating put on the fiberglass. Beyond this an outer coating of paint matching the aircraft colour can be used. However, this has to be done very carefully as the performance of the radar can degrade appreciably if the paint is too thick or if the application is uneven. Then once the plane is in the field, the paint degrades due to exposure to sun and rain, and abrasions due to sand blasting in flight. This leads to cracks/chips/pinholes, which along with the moisture contained in them degrades the performance greatly. In some cases, the performance was found to degrade to almost 50% (in civilian aircrafts). The normal desired performance of the radome is above 90% (recommended for civilian aircraft). So when the performance falls below this threshold, the paint has to be carefully removed and the radome has to be repainted. This is why with most military hardware (where aesthetics don't matter), you would find most radomes to be black, i.e. only with the anti-erosion coating. This becomes all the more important if the aircraft is going to be fielded in desert conditions. (Please read about what the US found with their aircrafts fielded in Afghanistan).

There was also a talk (in AI'13?) on AEW&C, how the dielectric performance and placement of arms holding up the antenna affect the overall performance of the antenna itself.

This is BS. the fact of the matter is that with their existing technology (or lack of), they cannot paint the radomes. Any professional paint company will be able to paint primer + 2 (or more) paint + (2 or more) clear coat within the thickness of a sheet of paper. Radar performance is not affected with paint of this thickness. It's obvious that DRDO lungi's are painting with distemper and paint brush (pronounced brew-sh).

BTW, the anti-erosion coat is nothing but what is called clear coat in the automotive industry. DRDO does not have a work etiquette that encompasses beauty or functionality.

Hobbes · Post by **Hobbes** » 03 Sep 2014 07:20

Leo.Davidson wrote: This is BS. the fact of the matter is that with their existing technology (or lack of), they cannot paint the radomes. Any professional paint company will be able to paint primer + 2 (or more) paint + (2 or more) clear coat within the thickness of a sheet of paper. Radar performance is not affected with paint of this thickness. It's obvious that DRDO lungi's are painting with distemper and paint brussh (pronounced brew-sh).

BTW, the anti-erosion coat is nothing but what is called clear coat in the automotive industry. DRDO does not have a work etiquette that encompasses beauty or functionality.

Talking through our hat, are we? A little googling would have shown you that the paint does make a difference. Check out http://www.radome.com/generic.aspx?id=197268 for information on how paint on radomes interacts with radar. Some key points:

Any paint finish that has a pearlescent or "metal flake" appearance should be avoided, since many of these paints contain very small slivers of aluminum or bronze metal called leafing pigments which can have a significant effect on radar signal.
......
Anti Static Coatings. These coatings contain a graphite or carbon black particles to make them semi-conductive so that static charges do not build up on the radome. These coatings should be used with discretion since a heavy application can result in attenuation of the radar signal. Also ensure that the coating type being considered is suitable for radome use. Since some anti static coatings are more conductive than others.

Erosion Resistant Anti-Static Finishes. Special purpose protective neoprene (MIL-C-7439) and polyurethane (MIL-C-83231) finishes are recommended for radomes where rain erosion is severe. The US Military specification MIL-R-7705 requires radome rain erosion protection on aircraft that operate at speeds of 250 knots or above. This protection should be applied to the leading portin of the radome.

These coatings are available in two classes Type 1 rain erosion resistant and type II rain erosion resistant with anti-static properties.

How much paint should be applied to a radome? For best results with regular aircraft finishes, apply one good topcoat 4 to 6 mils thick over a 2 mil thick primer base. However when special erosion resistant neoprene or polyurethane coatings are applied the required thickness is 10 to 12 mils.

When refinishing a radome, do not paint over existing coatings as the cumulative thickness of the old and new finishes will reduce the radome’s efficiency.

Singha · Post by **Singha** » 03 Sep 2014 07:25

is there a global tender out to source the right types of coating and paints here ?

the mighty E3 sentry also has a black rotodome with a white stripe that says here I am ! our phalcons are black with a white triangle inside.

Karan M · Post by **Karan M** » 04 Sep 2014 02:41

RoyG wrote:
Karan M wrote:An AEW&C which can look out to 300 km and will be detected on RWR at similar if not more ranges, and will be escorted by a flight of dedicated fighters, needs to think about paint on its vital sensors because they "stick out". Brilliant.
No need to draw down the pom pom's Karanji. I'm not knocking it's specs.

What would anybody you even understand about AEW&C specs RoyG? Best go back to your color coded fashion blogs.

RoyG · Post by **RoyG** » 04 Sep 2014 02:50

Ha, better than those cheap color coded DODO and HAL posters. Marketing at its finest.

Karan M · Post by **Karan M** » 04 Sep 2014 03:01

Leo.Davidson wrote:
indranilroy wrote: The black colour is because of the anti-erosion coating put on the fiberglass. Beyond this an outer coating of paint matching the aircraft colour can be used. However, this has to be done very carefully as the performance of the radar can degrade appreciably if the paint is too thick or if the application is uneven. Then once the plane is in the field, the paint degrades due to exposure to sun and rain, and abrasions due to sand blasting in flight. This leads to cracks/chips/pinholes, which along with the moisture contained in them degrades the performance greatly. In some cases, the performance was found to degrade to almost 50% (in civilian aircrafts). The normal desired performance of the radome is above 90% (recommended for civilian aircraft). So when the performance falls below this threshold, the paint has to be carefully removed and the radome has to be repainted. This is why with most military hardware (where aesthetics don't matter), you would find most radomes to be black, i.e. only with the anti-erosion coating. This becomes all the more important if the aircraft is going to be fielded in desert conditions. (Please read about what the US found with their aircrafts fielded in Afghanistan).

There was also a talk (in AI'13?) on AEW&C, how the dielectric performance and placement of arms holding up the antenna affect the overall performance of the antenna itself.
This is BS. the fact of the matter is that with their existing technology (or lack of), they cannot paint the radomes. Any professional paint company will be able to paint primer + 2 (or more) paint + (2 or more) clear coat within the thickness of a sheet of paper. Radar performance is not affected with paint of this thickness. It's obvious that DRDO lungi's are painting with distemper and paint brush (pronounced brew-sh).

BTW, the anti-erosion coat is nothing but what is called clear coat in the automotive industry. DRDO does not have a work etiquette that encompasses beauty or functionality.

Before calling a polite post full of details BS, look therein to your own post. Go look at the Jaguar MMR, XV-2000 etc radomes sometime & about what technology is available inhouse and demonstrated already & the kind of design considerations involved to minimize loss.

http://www.nal.res.in/pdf/Computational ... ratory.pdf

Looks like the nail polish, color matching types are now upset about paint schemes, talking about AWACs radomes not being of their desired color when the only things that matter are whether the radar & onboard sensors can look the farthest with minimal signal loss & interference.

It doesn't even matter if they can be painted green, red and yellow because these are AEW&C aircraft. By their very purpose, they are highly visible, high value targets & will be substantially defended under the (viable) thought that they are emitting and hence known to the opponent who will field RWRs.

On the other hand, paint or any external source which can cause interference/losses in either transmit or receive paths is going to be frowned on, because thats what is vital.

Karan M · Post by **Karan M** » 04 Sep 2014 03:03

RoyG wrote:Ha, better than those cheap color coded DODO and HAL posters. Marketing at its finest.

Perhaps they should have approached you dodette, so that you could have given them valuable tips on matching colors with your nail polish and purse collection. That's what you'd be good for.

PS: What do you know of marketing of any sort? Go on, tell us of your "practical experience". You tend to talk big, go on, tell us the number of manhours of knowledge you have about marketing.

Karan M · Post by **Karan M** » 04 Sep 2014 03:10

Bheeshma wrote:The range is 300 km just like the displacement of P-28 was 2500 tonnes. . I seriously hope they order at least 3-6 more to make up the numbers while developing the bigger AWACS.

Range will be around 300 km class (exact numbers will be always classified) because that's what a radar of that class & size usually achieves. The usual RCS test target India uses is 2 Sq Mtr. Against a 5sq mtr target (say a loaded JF-17), the range will increase by around 25%.

Note though, the FOV & number of targets tracked, operator work stations to parse greater details, ECCM capability etc will be more versatile than smaller radars. In practical terms, a 300 - 400 km class airborne picket will be invaluable for the IAF because of the number of fighters it has that either lack a radar of that range or lack a radar entirely.

The IAF will likely order more of the type after the initial few prove themselves. There are 3 on order notionally, but actual number is 2, because the third item was planned to be used for further tech development, trials etc.

Leo.Davidson · Post by **Leo.Davidson** » 04 Sep 2014 06:21

None of the responses from hobbes or karan are relevant.

In regards to hobbes response, the article does speak of interference, but does not admonish painting of the radome; Just look at the LCA, isn't it's radome painted. In regards to karan's response, the fact sheet is from an Indian lab and does not even make a case.

Goddamn, look at the Erieye which is an equivalent AWACS and it has a painted radome. So, the fact remains uncontested that DRDO lacks the paint technology for radomes and they & people in this forum are finding excuses for not painting it.

member_22539 · Post by **member_22539** » 04 Sep 2014 07:09

^Here cometh the paintnazi.

Indranil · Post by **Indranil** » 04 Sep 2014 08:28

Leo.Davidson wrote:None of the responses from hobbes or karan are relevant.

In regards to hobbes response, the article does speak of interference, but does not admonish painting of the radome; Just look at the LCA, isn't it's radome painted. In regards to karan's response, the fact sheet is from an Indian lab and does not even make a case.

Goddamn, look at the Erieye which is an equivalent AWACS and it has a painted radome. So, the fact remains uncontested that DRDO lacks the paint technology for radomes and they & people in this forum are finding excuses for not painting it.

You are right. Plus guess what, we don't have the money either. What to do?

Hobbes · Post by **Hobbes** » 04 Sep 2014 08:44

indranilroy wrote:
Leo.Davidson wrote:None of the responses from hobbes or karan are relevant.

In regards to hobbes response, the article does speak of interference, but does not admonish painting of the radome; Just look at the LCA, isn't it's radome painted. In regards to karan's response, the fact sheet is from an Indian lab and does not even make a case.

Goddamn, look at the Erieye which is an equivalent AWACS and it has a painted radome. So, the fact remains uncontested that DRDO lacks the paint technology for radomes and they & people in this forum are finding excuses for not painting it.
You are right. Plus guess what, we don't have the money either. What to do?

member_26622 · Post by **member_26622** » 04 Sep 2014 10:03

Where is the follow on order for 3~6 more desi AWACS platforms? It takes 3 years to roll these planes out and need an order out this year to maintain continuity in deliveries.

Read some alternate platforms are been considered but unsure why we want to keep wasting time and donating money on new platforms. What's wrong with Embraer jets or are is it another repeat case of import drool for super expensive euro chamak challos.

merlin · Post by **merlin** » 04 Sep 2014 10:47

nik wrote:Where is the follow on order for 3~6 more desi AWACS platforms? It takes 3 years to roll these planes out and need an order out this year to maintain continuity in deliveries.

Read some alternate platforms are been considered but unsure why we want to keep wasting time and donating money on new platforms. What's wrong with Embraer jets or are is it another repeat case of import drool for super expensive euro chamak challos.

Perhaps the radar really is a success and they want a bigger platform now? I think the decision has been made for the bigger platform and hence no more Embraer are to be ordered? Operational cost wise these smaller platforms may be more cost effective so I'm not sure why the new platform order numbers are 6.

Aditya_V · Post by **Aditya_V** » 04 Sep 2014 12:00

Well why big platform ordered?

srin · Post by **srin** » 04 Sep 2014 16:29

It would be a huge program management mistake if they stop the AEW in the hope of getting the AWACS. They don't know (or have control over) the timelines for the new platform (Airbus or something) to be selected and contract signed. They don't know (or have control over) how long it will take for the modifications to be designed and completed (with flight testing). They may probably be under-estimating the time it will take to design the chappathi-style antenna on top (with cooling etc), weight restrictions etc. It will easily take atleast another 5 years for the first one to be IOC'ed.

I read on the wiki that we have options for 7 more. I think we should exercise those. By the time the AWACS platform is ready, we'd have a good fleet of less endurance and less capable but good enough AEWs that can be distributed across both eastern and western sectors with a good number in reserve.

abhik · Post by **abhik** » 04 Sep 2014 17:43

Also a dedicated manufacturer should be found. In the future the same entity can manufacture the follow on AWACS, MSA (which are already in development) and possibly mid air refuler in the future.

member_26622 · Post by **member_26622** » 05 Sep 2014 03:55

Who will we 'Export' an Indian built DRDO AWACS to if we keep changing the configuration so often ourselves. No one buys a small production run or end of life platform, in fear of exorbitant upkeep and future upgrade cost (except us - Indians going by the Rafale tamasha).

The market for a low cost AWACS is much bigger than a Big chapati dhamaka- plus we cannot compete in the medium or big category given our lack of experience in the first place (Israel Phalcon, US E3 and Euro Wedgetail?). Embraer jets are likely the lowest cost platform option over Euro shop or Canadian Bombardier. Now if sanity prevails and we ramp up to make 10 units, export potential will increase and lowers lifetime costs for us.

In hindsight, we should have gone for Wedgetail as it is on 737 platform - same as P8I's. It's 100 million $ plane versus a 20 million $ Embraer though. Ideally, we should field Wedgetail and Embraer with DRDO radar to maintain commonality + build higher nos (Paki midgets field 6 AWACS today in comparison).

Overall - Painful to see us repeatedly throw away all the hard work and investments. But MOD\IAF have shown a particular affection to 'variety' going by our acquisition history. More opportunities to be fleeced over contracts and spare parts i guess.

member_26622 · Post by **member_26622** » 05 Sep 2014 04:00

Adding on the Paint discussion -

American Airlines 'never' painted their Boeings, except the logo. The jets were eyesore bare shiny aluminium - weight reduction from not using paint added up to millions of $$$ in fuel savings. They even ordered Airbuses without full paint job and realized that the composite body is black and inconsistent in color - ended up painting them to match up with the Boeing fleet.

Don't see a good reason to paint the DRDO built radome cover - just replace the composite cover sooner!

Eric Leiderman · Post by **Eric Leiderman** » 05 Sep 2014 05:14

Have any of the forces asked for a Embracer and what are their projected numbers, Maybe a small Jstar could evolve.

Singha · Post by **Singha** » 05 Sep 2014 09:26

we do have a nasty habit of fiddling around with small lots, numerous changes and never tend to produce anything in volume properly with exception of ongoing Akash production run.

our navy except for the sarayu and sukanya class does not have any class of more than 3 ships. and even within these 3 there are certain diffs as I believe in the delhi class.

Karan M · Post by **Karan M** » 05 Sep 2014 09:54

Leo.Davidson wrote:None of the responses from hobbes or karan are relevant.

In regards to hobbes response, the article does speak of interference, but does not admonish painting of the radome; Just look at the LCA, isn't it's radome painted. In regards to karan's response, the fact sheet is from an Indian lab and does not even make a case.

Goddamn, look at the Erieye which is an equivalent AWACS and it has a painted radome. So, the fact remains uncontested that DRDO lacks the paint technology for radomes and they & people in this forum are finding excuses for not painting it.

The brilliance of your response does not even deserve a thoughtful answer.

JTull · Post by **JTull** » 05 Sep 2014 16:12

This conversation is hilarious. Certain lobbies are scraping the (paint) barrel to paint Indian products badly.

Prem Kumar · Post by **Prem Kumar** » 06 Sep 2014 09:28

Please don't be harsh on Leo Davidson. He is earning his secular stripes & is rightfully concerned why the radome is not painted green

Yagnasri · Post by **Yagnasri** » 06 Sep 2014 16:28

In the evil rule of NM all peaceful secularists are getting harassed.

abhik · Post by **abhik** » 06 Sep 2014 19:25

Prem Kumar wrote:Please don't be harsh on Leo Davidson. He is earning his secular stripes & is rightfully concerned why the radome is not painted green

I guess he didn't get the memo because black is the new secular colour

.

SaiK · Post by **SaiK** » 07 Sep 2014 03:05

http://timesofindia.indiatimes.com/indi ... 897554.cms
We have got a big loop hole!

srin · Post by **srin** » 07 Sep 2014 10:21

We don't know. All that is confirmed is that it wasn't known to ATC. But it had an active transponder (otherwise TCAS wouldn't have generated an alert).
We don't know if IAF also missed it - unlikely, but they won't be advertising it. Or if it actually was an IAF plane.

member_20317 · Post by **member_20317** » 07 Sep 2014 11:46

SaiK wrote:http://timesofindia.indiatimes.com/indi ... 897554.cms
We have got a big loop hole!

Link says:

gave the jitters to some international commercial flights flying over the Arabian Sea about 450 to 480km from Mumbai's coastline

<snip>

Since the warning came from planes flying at 36,500 feet, chances are the unidentified aircraft was on a reconnaissance flight as fighter jets don't fly that high.

Mentions Diego Garcia which I checked is 1800 km from Mumbai coastline.

Don't know where the loophole is but it is clear where the hole is.

BTW read the comments they are quite funny same as the reportage.

member_27164 · Post by **member_27164** » 07 Sep 2014 12:07

There is mistake in the article. The last line says the plane was at 36500ft and should be on recce because fighter planes dont fly at that height. Overall i dont think the plane would not have been caught on military radars. how come all air force, naval - coastal and ship borne radars fail at same time specially near city like mumbai?

member_27164 · Post by **member_27164** » 07 Sep 2014 17:32

indranilroy wrote:Beautiful pictures from CABs (courtesy Tarmak007).

Which plane is that in the middle?

sattili · Post by **sattili** » 07 Sep 2014 17:56

^^^^^^
That is a HS-748(Avro) flight test bed http://drdo.gov.in/drdo/labs/CABS/Engli ... light.html

JaiS · Post by **JaiS** » 28 Sep 2014 09:02

DRDO ready to deliver AEW&C to Air Force

Defence Research and Development Organisation (DRDO) is ready to deliver the Brazilian Embraer aircraft-based, indigenously built Airborne Early Warning and Control (AEW&C) to the Indian Air Force as soon as it is ready to receive it. At the moment, the IAF is training its personnel who can operate the systems of the aircraft, at Bangalore-based Centre for Airborne Systems (CABS). The process should be over by February of next year.

Dr K Tamilmani, the director general of aeronautical systems and Dr S Christopher, programme director (AEW&C) and director, CABS said on Thursday that the laboratory has developed an indigenous Active Electronically Scanned Array (AESA) radar that has been fitted on the aircraft and is actually functioning for almost a year. The air-to-air function of the radar has been tested and certified, while air-to-sea functions are being tested.

Christopher stated that the ‘technical readiness level’ of the AEW&C is of the order of eight on a scale of ten. In a crowded environment, the aircraft system can ‘correlate, identify, classify and threat response of 500 airborne targets can be tracked, out of which 16 enemy targets can be simultaneously designated.’

There are five work-stations where operators can sit and work, with one being solely for dedicated for ‘communication support measure.’ The aircraft can loiter for five hours independently and with refueling, another four hours can be added to the sortie. It will need some friendly fighter aircraft support, with satellite communication link directly to Vayu Bhavan, IAF headquarters.

The Embraer system has data links, voice communication facility, 32 fighter aircrafts can remain connected while in air, and the ‘air support picture’ created by the operators. It can reach altitudes of 25,000 to 30,000 with a range of 300 kms. Significantly, the AESA radar will have ‘look down’ ability. The radar has 1,257 amplifiers.