Airborne Early Warning & Control: News & Discussion

The Military Issues & History Forum is a venue to discuss issues relating to the military aspects of the Indian Armed Forces, whether the past, present or future. We request members to kindly stay within the mandate of this forum and keep their exchanges of views, on a civilised level, however vehemently any disagreement may be felt. All feedback regarding forum usage may be sent to the moderators using the Feedback Form or by clicking the Report Post Icon in any objectionable post for proper action. Please note that the views expressed by the Members and Moderators on these discussion boards are that of the individuals only and do not reflect the official policy or view of the Bharat-Rakshak.com Website. Copyright Violation is strictly prohibited and may result in revocation of your posting rights - please read the FAQ for full details. Users must also abide by the Forum Guidelines at all times.
ldev
BRF Oldie
Posts: 2006
Joined: 06 Nov 2002 12:31

Re: Airborne Early Warning & Control: News & Discussion

Postby ldev » 05 Jan 2020 22:13

And as for numbers game the JF-17 Block 3 made it's maiden flight a few days ago:

Sino-Pakistani JF-17/FC-1 Block III prototype makes maiden flight

A further development of the Block II variant, the JF-17/FC-1 Block III version appears to be the result of a comprehensive upgrade of the aircraft that is set to include a new active electronically scanned array (AESA) radar.

From the few images that have emerged so far – which show the aircraft armed with two PL-5EII short-range air-to-air-missiles (AAMs) – the most visible changes in the Block III variant are a new wide-angle holographic head-up display – similar to the one used in China’s fifth-generation J-20 fighter aircraft – and an imaging infrared (IIR)-based missile approach warning system – the sensors of which are located behind the engine air intakes as well as on top of the vertical tail fin, similar to those fitted on China’s J-10C fighter.


Production is estimated at 25 units per year.

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 05 Jan 2020 22:22

There is a lot of discussion here about the S-400 as a counter for PAF AEW coverage. I should point out that the intent of the PAF in a wartime scenario should be considered when looking at this. What is the defensive goal of the PAF? They need to maintain coverage over their border (without ever peering deep into India), and accomplish their objective of detecting any IAF strike package that enters their airspace. And given that their fighters are going to be flying directly above their home airbases during this scenario, they can be available on shorter notice than any IAF support that can be brought in from far away. So the defensive scenario favors the PAF AEW fleet.

Consider the possible S-400 coverage on the Indian border during wartime (red circles). The detection range for a ground-based S-400 radar in the mountains is terribly constrained, and hence the smaller red circles in the J&K region. However, and AEW flying at 35k feet altitude will still detect other airplanes at 20k altitude and higher, and so their ranges are not as severely affected.

Image

You can see from this "theoretical" plot that even if the IAF forward-deployed its S-400 systems (which, BTW, is not a given considering their strategic anti-ballistic missile usage), the PAF still is able to maintain coverage over its borders by flying outside the coverage perimeter of the S-400. Obviously they cannot peer deep into India from these positions.

Also note: any large support aircraft (turbo-prop or jet-engined) caught inside the kill-zone of a SAM is going to go down to a volley of missiles. The speed difference between a jet engine and a turboprop will only be key at the perimeter of the SAM coverage where they can peek in and peek out before a SAM volley is launched at them.

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 05 Jan 2020 22:27

abhik wrote:I remember a decade or so back somebody had taken a compass and drawn 3 circles of 500 km on the Indo-Pak border, to naively show its coverage and how awesome it would be. When its time comes I'm sure S400 will turn out to be as equally disappointing as against it gold plated expectations as the Phalcons were.


I took the lead this time to naively generate the range circle plots for this discussion! :D

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 05 Jan 2020 22:29

fanne wrote:Boy what a way to start your day - with higher BP


Its what I do best. :rotfl:

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 05 Jan 2020 22:53

nam wrote:PAF does have more AWACS and is said to be able to monitor 24/7. If that was the case, what happen on Feb 26? when our Mirages had a free run! How could a coverage of 24/7 not detect bogies coming in!

Compare that to our monitoring on Feb 27. Did any PAF jets managed to get in?


I think the plots and analysis I posted previously was to do with "surge" situations in wartime. Obviously nobody is going to wear out their expensive airplanes by flying continuous 24x7 coverage during peacetime. 24X7 surge operations cost a lot in both operational expenses as well as from the lifetime of the airframe. Expect surging to be used only for 2-3 weeks maximum before even the flight crews are completely exhausted.

So yes, any preemptive surprise strike package without declaration of war will get through at the mercy of the available ground-based radar coverage. The IAF had minimal opposition during its strike on Feb 26 for this reason. It would have been the same if the PAF was doing that to us.

On Feb 27, everyone was in surge mode and all assets were in the air. That is where the IAF AEW coverage deficiency became glaringly visible.

nam wrote:Imagine we had lot more AWACS on station and we were able to detect all PAF bogies. Then what? What we lack is ways to counter the long range targets.


That is a good problem to have, isn't it? The idea that we have all the AWACS coverage we need and we are now ready to move to the next problem of using that coverage to do other stuff? I do think that these two questions should not be conflated and used interchangeably. You need both problems to be solved.

VKumar
BRFite
Posts: 581
Joined: 15 Sep 1999 11:31
Location: Mumbai,India

Re: Airborne Early Warning & Control: News & Discussion

Postby VKumar » 06 Jan 2020 00:08

Can the Do228 be equipped with early warning system and used as a 'trip-wire' ? We can manufacture these afresh.

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 06 Jan 2020 00:16

VKumar wrote:Can the Do228 be equipped with early warning system and used as a 'trip-wire' ? We can manufacture these afresh.


Nope. It has neither the internal space nor the engine power to host an external radar beam. Think bigger. C295 might be an option.

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 06 Jan 2020 01:23

Look, there is a simple first-principles approach to choosing airplane types for airborne radar systems. I will lay it out here for discussion purposes.

Think in terms of power. If you google the radar range equation, you will notice that the maximum range for a radar is determined by the 4th root of the power supplied to it. On a ground system, you can pump in as much power as needed, and so you are primarily constrained by the terrain (eg. mountain ranges, curvature of the earth etc.). On an airborne system, that power has to come from the airplane. Now, either you carry an onboard source of power, or you hook up generators to the airplane engines to divert electrical power to the radar.

But the airplane also needs power from the engines to fly. So you cannot divert all the engine power to the radar. This brings in the power-to-weight ratio of the airplane. The higher the power-to-weight ratio, the more juice you can extract for your radar system.

Now, as a mathematical exercise, let's use the E-3D AWACS as a reference point. We know from its public data that the electrical generator attached to each of the 4 engines generates 1 MW of power for the radar. So a total of 4 MW for the radar system. Going back to the radar equations, let's also assume that for comparison purposes, all of our airplanes will have the same radar capability (Gains, frequency, target RCS etc.). In other words, we are assuming a world where all of the different AEW/AWACS designs have the same radar technology (which obviously is not true). So this is a conservative comparison.

If you then compute the percentage of the power available that is used in the E-3D for its radar as a function of its overall available power and weight, then with the above assumptions, you can plot for all airplanes the maximum range of the radar that they will have (as shown here):

Image

Notice how quickly the turbofan/turbojet engine airplanes separate themselves into a different bubble from the propeller airplanes. Both in terms of radar ranges as well as power-to-weight ratios.

Some noticeable items from the above plot:
1. The Chinese ZDK-03 is the most powerful propeller-powered airplane with a radar on top (not counting some C-130 mods in the USA). But we know its radar range is much smaller than what the plot above shows. This is because we are assuming the E-3D radar tech is inside the ZDK-03. Obviously that isn't true, and the Chinese radar tech is poorer quality, so despite the potential of the airplane, its actual capability is lower.
2. Do-228 is not an option as I have mentioned in my previous post. You can see that clearly here.
3. C-295 will barely make the grade as well.
4. Notice that the Phalcon has a lot of power to play with, but because of its poor endurance and unsuited airframe, loses out.
5. Notice where the A-330 AWACS(I) would fall on that plot! As I said before, this project needs to be advanced on high priority. The closest in terms of capability to it would be the E-3D and the E-767 (Japan).

brar_w
BRF Oldie
Posts: 8756
Joined: 11 Aug 2016 06:14

Re: Airborne Early Warning & Control: News & Discussion

Postby brar_w » 06 Jan 2020 01:32

Where are the data for that chart coming from? A cursory look shows a few errors. Also, not all the sensors on that chart operate in the same band or are optimized for the same mission. You have frequency diversity there extending from 800 MHz through 5 GHz so efficiency and how the available power is utilized is going to be different as is what the sensor is optimized for.

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 06 Jan 2020 01:36

brar_w wrote:Where are the data for that chart coming from? A cursory look shows a few errors. Also, not all the sensors on that chart operate in the same band or are optimized for the same mission. You have frequency diversity there extending from 800 MHz through 5 GHz so efficiency and how the available power is utilized is going to be different as is what the sensor is optimized for.


The power-weight ratio is for the airplane, not the radar.

I am sure there will be a lot of generalization and other errors in this plot relative to the real physical airplanes. I am assuming very basic first-principles rules here. Also note my assumptions: I am assuming that the same E-3D tech is being put on all airplanes shown here. Also assuming the maximum power for the E-3 electrical generators as my data point. Just to even the playing field. The real requirements will obviously vary substantially. If I start adding frequency diversity and all that on top of it, the analysis becomes a mess real fast. And most of that data would be unavailable anyway.

Just treat this as a simplified energy analysis.

brar_w
BRF Oldie
Posts: 8756
Joined: 11 Aug 2016 06:14

Re: Airborne Early Warning & Control: News & Discussion

Postby brar_w » 06 Jan 2020 01:41

But without that it becomes quite meaningless. For example, an AWACS pushing a C-band sensor is optimized for different trade-offs vs something pushing an L-band or UHF band sensor which is going to be way more efficient. Designers have made those trades and have chosen efficient ESA's within SWaP constraints by choosing sensors in the UHF or L band. When choosing those, power limitations may not even matter to the same extent as one might think by simply looking at power availability of the two platforms.

Similarly, those turboprop aircraft fly very different profiles (altitudes) and have radar horizon limitations (just like every other aircraft on that list but more severe given the difference in optimal cruising altitude). Additionally, at very very long ranges you are essentially looking at things like rocket launches or ballistic missiles as the altitude you are covering is so limited that tactically you will be placed at a different location if SA at those ranges was valued enough to matter tactically. Same thing with frequency diversity and how efficiently these diverse sensors surveil airspace. You have some sensors there that are optimized for surveiling large swaths of airspace for things like cruise missiles (smaller RCS) against clutter. Others are designed for different missions with higher level of discrimination afforded by their sensor choice. Also, in the AEW realm raw ranges are quite meaningless as the focus is on airspace volume and efficiently covering that with the available workstation footprint onboard. There is quite a bit of multi-tasking going on and you are unlikely to be responsible for airspace over such large swaths of airspace..

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 06 Jan 2020 01:50

brar_w wrote:But without that it becomes quite meaningless.


I disagree. There is a lot of general insight to be gained by looking at simple energy/power analysis. Especially when all the assumptions have been laid out for clarity.

brar_w wrote: For example, an AWACS pushing a C-band sensor is optimized for different trade-offs vs something pushing an L-band or UHF band sensor which is going to be way more efficient. Similarly, those turboprop aircraft fly very different profiles (altitudes) and have radar horizon limitations (just like every other aircraft on that list but more severe given the difference in optimal cruising altitude).


Fully agree.

But assuming that all airplanes are using (for the sake of argument):
1. Same C-band sensor (or any other sensor suite, but kept common across airplanes for the analysis).
2. Same electrical systems and generators.
3. Fly over the same terrain and altitude profiles

Would the design then not be limited by available power?

Note that you can design one system for an L-band radar on a turboprop for oversea operations that is much different than a C-band AWACS on a turbo-fan airplane for overland operations. But that is missing the point with what I posted above.

brar_w
BRF Oldie
Posts: 8756
Joined: 11 Aug 2016 06:14

Re: Airborne Early Warning & Control: News & Discussion

Postby brar_w » 06 Jan 2020 01:55

vivek_ahuja wrote:But assuming that all airplanes are using (for the sake of argument):
1. A C-band sensor (or any other sensor)
2. Same electrical systems
3. Fly over the same terrain and altitude profiles

Would the design then not be limited by available power?


Because you pick the sensor that is best optimized for the mission needs, and the platform that you can afford or field in a sizable number. If one were just looking at one very specific metric (raw range against X RCS) then one can open up a sizable sensor trade space and match that to the available platform footprint. This is done by radar designers all the time and has for decades. Even on ground surveillance sensors, when you have a hard to meet surveillance volume target but at the same time also have to fit the sensor within a space limitation for deployability (like say a C-130) and power generator (fuel required) footprint then you exercise more efficient parts of the spectrum. One such example of that trade is THIS. Similarly, the E-7 represents a similar trade on the AEW side of things. The need for a more affordable, and efficient platform along with a low drag tophat design moved them to a fixed L band sensor which is obviously different from the C-band sensor on the E-3. The pocket AWACS is is still probably getting better than 2/3 the performance of the much larger E-3 within a very narrow scope of performance metrics despite being significantly less endowed when it comes to SWaP. In other times when you have very rigid requirements that force you towards a very inefficient part of the spectrum, but you still need very high performance you just have to suck it up and produce something that is large and consumes an insane amount of power. Something like this SBX-X-band sensor for example.

So the difference is much more nuanced than just a raw look at power generation ability as each sensor and sensor-platform is optimized for one other. Very rarely, if ever, does one design a radar and then go looking for a suitable platform. Most often, if not always, you start with a requirement, cost, logistical footprint, and performance need and then optimize accordingly. In that case, each system on that chart represents different trades made based on unique needs and use cases for those operators or those that influenced its design. A very direct SwAP for SwAP comparison is practically meaningless..

In other words, if you have a competent sensor design team, and access to cutting edge technology, you can negate much of the raw power generation advantage, as it applies to a very specific metric like sensor surveillance performance, by optimizing the sensor. Lockheed built a sensor on the E-2D that has a stated range in excess of 500 km despite very little SWaP to play with given the platform limitations. If you speak to those in the know, they usually look at bottlenecks which are the computing power, the # of work-stations, crew fatigue and rest, the sensor density and the ability to execute multiple tasks concurrently over a reasonable sized air-space. You are either well equipped in that department (with growth) or are compromised and therefore forced to prioritize missions. Very rarely would you have an operator tell you that they wished they had additional sensor performance. With second and third generation of solid state sensors you can get very very good sensor performance and coverage within tight SWaP tolerances because you have access to lower frequency sensors that can now (thanks to advancement in signal processing and other advancements) come into play in a way unlike choices available decades earlier..
Last edited by brar_w on 06 Jan 2020 04:36, edited 2 times in total.

Karan M
Forum Moderator
Posts: 19508
Joined: 19 Mar 2010 00:58

Re: Airborne Early Warning & Control: News & Discussion

Postby Karan M » 06 Jan 2020 04:00

vivek_ahuja wrote:You can see from this "theoretical" plot that even if the IAF forward-deployed its S-400 systems (which, BTW, is not a given considering their strategic anti-ballistic missile usage), the PAF still is able to maintain coverage over its borders by flying outside the coverage perimeter of the S-400. Obviously they cannot peer deep into India from these positions.


Which is the point of both the Meteor and the S-400 (and hopefully soon, the RVV-BD) that they will allow the IAF to push the PAF AEW&CS fleet back into the PAF hinterland, preventing them from looking deep into India.

This has 2 advantages:
1. Prevents them from adequately monitoring IAF ops in peacetime learning from our tactics and surge capabilities.
2. At times of conflict, reduces the capability of doing airspace management on "the cheap" via looking deep into India, which was possible by flying defensive AEW&CS round the clock but surging fighters only when necessary, hence avoiding expensive wear and tear on the fighter fleet.

Further:
3. I believe as DRDO programs scale up (Akash NG, HPR, XRSAM, AWACS-India) and DRDO has more radar designs to quickly develop variants off of, the IAF will also ask DRDO to look at aerostat radars to supplement its AEW&CS fleet and enhance the coverage of its SAM/BMD network.
4. DRDO is already developing mountain radars (long range, weather resistant, weight/volume optimized) but aerostats would partly address the challenges caused by terrain masking.

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 06 Jan 2020 04:23

Karan M wrote:3. I believe as DRDO programs scale up (Akash NG, HPR, XRSAM, AWACS-India) and DRDO has more radar designs to quickly develop variants off of, the IAF will also ask DRDO to look at aerostat radars to supplement its AEW&CS fleet and enhance the coverage of its SAM/BMD network.
4. DRDO is already developing mountain radars (long range, weather resistant, weight/volume optimized) but aerostats would partly address the challenges caused by terrain masking.


I am a big fan of the Aerostat approach. It is relatively cheap to produce, easier to maintain and you can have very long loiter times at station. I think the big issue with Aerostats is where to store the power supply. The issue, I think, is that if you provide on-board power, then its limited by the fuel capacity of the generators producing the electrical power. And after that you have to lower the Aerostat down, refuel and launch again. The ascent and descent from high altitude is also not very fast (is that correct?) for such systems.

Simple Wiki search gives this for the US Tethered Aerostat Radar System:
Image

The hull of the aerostat contains two parts separated by a gas-tight fabric partition. The upper chamber is filled with helium and provides the aerostat's lifting capability. The lower chamber of the hull is a pressurized air compartment. The hull is constructed of a lightweight polyurethane-coated Tedlar fabric. An airborne engine drives the generator, supplied by a 100-gallon diesel fuel tank.

Beginning in the late 1990s, the aerostat sites were equipped with Lockheed Martin 420K aerostats. This blimp carries the Lockheed Martin L-88 as its primary payload, a surveillance radar with a range of 370 km (200 nm). The 420K's envelope shape, fin design, and cable attachment points are further optimized for high aerodynamic stability and easy ground handling.

...

Operational availability is generally limited only by the weather (60 percent standard) and routine maintenance downtime. The aerostats are stable in winds below 65 knots (120 km/h). Aerostat and equipment availability averages more than 98 percent system-wide.

For security and safety reasons, air space around Air Force aerostat sites is restricted for a radius of at least two to three statute miles and an altitude up to 15,000 feet (4,600 m).


The weather is not an issue up in the desert of Rajasthan and Gujarat. And 15,000 feet (roughly) over that flat terrain would serve just fine, I think. I wonder what the endurance of these things is like before the on-board electric generators for the radar have to be refueled.

Supposedly, the DRDO guys also have the "Akashdeep" Aerostat up at the trials stage, but that is for EO ISR activity only.
DRDO Akashdeep Aerostat

I do think the radar power issue will be a limiting factor for Aerostats compared to fixed-wing AEW aircraft...unless they figure out how to transmit power from the ground station to the Aerostat without losses along the way. Its part of the same problem for the Hybrid-electric airplanes as well.

Karan M
Forum Moderator
Posts: 19508
Joined: 19 Mar 2010 00:58

Re: Airborne Early Warning & Control: News & Discussion

Postby Karan M » 06 Jan 2020 04:37

The issue has been of gas leakage post deployment. You periodically have to lower the aerostat, refill, redeploy.
We have 2 Israeli aerostats. US supplied aerostat, Israeli radar. One was damaged because of mishandling and was to be repaired.

The other issue in mountains, is weather. Heavy wind conditions would be a challenge. As would be deploying the unit in a compact form factor.

The power has not been mentioned as a significant concern. As the PSU is static, and ground based, you have leeway, provided you have space but then again, you could deploy in the plains and due to altitude of deployment still get some coverage over mountainous areas, valleys.
A 370-400km ROA is very very useful for us but will likely be reduced in the above case (mountain deployment).

However, the biggest issue why IAF hasn't gone overboard (IMHO) with aerostats, is that they are relatively fixed and till a S-400/MRSAM/Akash deployment occurs, vulnerable. They need to be carefully protected as they are, for our budgets, quite expensive.

brar_w
BRF Oldie
Posts: 8756
Joined: 11 Aug 2016 06:14

Re: Airborne Early Warning & Control: News & Discussion

Postby brar_w » 06 Jan 2020 04:43

Power supply via a fiber optic tether to a ground station did not prove to be a challenge in even the largest aerostat based projects (either exclusive/primary or supplemental). The challenge has been and continues to keeping the thing performing in adverse weather and over time and to keep the tether in tact as they get larger, heavier and more used (constant orbits for 30-60 days at a time) i.e 3-5 metric ton payloads. The JLENS mounted a rotating 5000+ T/R module X band AESA on one of the systems while the other carried a huge VHF AESA radar along with data-link transmitters and IFF systems. I used to drive past it on my way to work for a couple of years when it was up and running as a prototype system..Then it de-tethered and flew a few hundred miles and landed in Amish country...

Smaller aerostats then that with lower frequency sensors (less power hungry) are operational the world over. The problem there is to get reliable constant surveillance in all weather and keeping them up and running during war..as would be required to have them as part of a reliable air-defense system. They are also usually not re-deployable, making their locations known and being prime targets.. The future of advanced AEW is clearly unmanned aircraft and "sensor carriers" that operate with very high bandwidth next gen. long range data-links (current AWACS architecture is the way it is because separating the sensor data from the Command and Control and processing and tasking has been a huge technical hurdle and beyond current level of mature tech) ..we should begin to see those come online within the next 10-12 years..you need something that is small, survivable, yet can generate large amounts of sensor-data and transmit it rapidly for organic processing (processing at the source of consumption as opposed to status quo).

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 06 Jan 2020 05:03

brar_w wrote:Power supply via a fiber optic tether to a ground station did not prove to be a challenge in even the largest aerostat based projects. The challenge has been and continues to keeping the thing performing in adverse weather and over time and to keep the tether in tact as they get larger, heavier and more used (constant orbits for 30-60 days at a time).


Very interesting. I haven't looked into this at all and wasn't aware that this issue was resolved. So they have ditched the onboard power sources (aside from backup/secondary requirements) in lieu of the ground-based fiber optic power transmission?

Do you have some good places to read up on the operational side of this? The 30-60 day orbit sounds fascinating for an AEW platform.

brar_w wrote: I used to drive past it on my way to work for a couple of years when it was up and running as a prototype system..Then it de-tethered and flew a few hundred miles and landed in Amish country...


:D

I do agree, though, about their vulnerability in any active wartime scenario. I think they work well in peacetime to keep and eye on the border or to prevent drug smugglers etc. But their static nature is a death sentence for real war scenarios.

Unmanned distributed sensor platforms are probably realistic as the next step in evolution.

brar_w
BRF Oldie
Posts: 8756
Joined: 11 Aug 2016 06:14

Re: Airborne Early Warning & Control: News & Discussion

Postby brar_w » 06 Jan 2020 05:07

vivek_ahuja wrote:Very interesting. I haven't looked into this at all and wasn't aware that this issue was resolved. So they have ditched the onboard power sources (aside from backup/secondary requirements) in lieu of the ground-based fiber optic power transmission?


It depends upon the application. If your sensor and supporting equipment is large, weighs in the 6-8K lbs class, and the system is required to establish a constant 30-60 day orbit without any downtime then it gets difficult to rely on exclusive organic power supply. You'd run out of fuel most likely. But if you have a very highly efficient surveillance sensor that is operating at low power requirements over a relatively smaller volume of air-space (as you would if you are using it for border protection against drug traffickers for example) then you can probably get away with it as you can overlap coverage and refuel. The JLENS was tasked with both surveillance and Fire-Control-track generation against cruise and ballistic missiles at medium to long ranges given its roughly 3K meter altitude. That basically amounts to the sensor footprint of a medium range SAM floating up at 10,000 ft. That gets complicated very rapidly.

putnanja
BRF Oldie
Posts: 4460
Joined: 26 Mar 2002 12:31
Location: searching for the next al-qaida #3

Re: Airborne Early Warning & Control: News & Discussion

Postby putnanja » 06 Jan 2020 07:14

Why isn't Boeing 737/Airbus A320 class planes insufficient for AEW roles? I still think A330 is a bit oversized for the AEW role. A321/B737s can now fly for upto 4000nm and can stay in air for 6-8 hours.

arvin
BRFite
Posts: 358
Joined: 17 Aug 2016 21:26

Re: Airborne Early Warning & Control: News & Discussion

Postby arvin » 06 Jan 2020 08:17

^^
Due to Engine power I guess. Engines for 180 seaters could have less power and than 250 seaters. Same time using a B777 350 seater would be a overkill.

chola
BRF Oldie
Posts: 4607
Joined: 16 Dec 2002 12:31
Location: USA

Re: Airborne Early Warning & Control: News & Discussion

Postby chola » 06 Jan 2020 08:26

Vivek, Brar, that is a fantastic discussion on a topic I had never really looked into. Now I am intrigued!

Actually the whole AWACS discussion over the past pages is very good. Thank you for driving it, Vivek. (I appreciate the S400 range circles.)

SBajwa
BRF Oldie
Posts: 5360
Joined: 10 Jan 2006 21:35
Location: Attari

Re: Airborne Early Warning & Control: News & Discussion

Postby SBajwa » 06 Jan 2020 08:38

Thank you Vivek, Brar and rest!!! Keep up the good work

manjgu
BRF Oldie
Posts: 2333
Joined: 11 Aug 2006 10:33

Re: Airborne Early Warning & Control: News & Discussion

Postby manjgu » 06 Jan 2020 09:03

what vivek provided was AWACS 101..basic issues/constraints and a simplified model for understanding. that there were two distinct sets was interesting. systems like S400 and HQ9 etc are not silver bullets which will solve all the problems. they have to be part of a multi tiered AD network so survive in a war situation. but S400 as part of a multi tiered/dense AD network will be v formidable. a S400 unit itself needs to be protected by AD assets to protect it from surge/ saturation attacks. so all in all a very very complex issue. PAF becoming JF17 heavy force which is being touted as a point defence ..does PAF have enough assets to carry out missions inside Indian Air space is the Q??

manjgu
BRF Oldie
Posts: 2333
Joined: 11 Aug 2006 10:33

Re: Airborne Early Warning & Control: News & Discussion

Postby manjgu » 06 Jan 2020 09:06

publicly advertised ranges of S400 are anywhere from 400 to 500 km. the longest ranged missile advertised is 400 km !! if u draw circles with a 400 km radius along 3 well choosen points on indo pak border, it covers everything from north to south including mumbai. http://freemaptools.com/radius-around-point.htm is a good tool to chk that.

Karan M
Forum Moderator
Posts: 19508
Joined: 19 Mar 2010 00:58

Re: Airborne Early Warning & Control: News & Discussion

Postby Karan M » 06 Jan 2020 09:20

Vivek, that's a brilliant chart. Completely agree with your reasoning and the approach you have taken.

nam
BRF Oldie
Posts: 3570
Joined: 05 Jan 2017 20:48

Re: Airborne Early Warning & Control: News & Discussion

Postby nam » 06 Jan 2020 13:12

putnanja wrote:Why isn't Boeing 737/Airbus A320 class planes insufficient for AEW roles? I still think A330 is a bit oversized for the AEW role. A321/B737s can now fly for upto 4000nm and can stay in air for 6-8 hours.

IAF wants longer on station.

And we will never have enough tankers to feed awacs. Better off with A330.

rohitvats
BR Mainsite Crew
Posts: 7726
Joined: 08 Sep 2005 18:24
Location: Jatland

Re: Airborne Early Warning & Control: News & Discussion

Postby rohitvats » 06 Jan 2020 14:50

habal wrote:my guess is IAFs priorities lie in obtaining western platforms for maximum baksheesh and safe sorties. I mean a pilot has to log x flying hours any given year, and their reasoning may be rather than using russian or Indian systems the best, most risk averse and safest possible option is to use western platforms like m2k & rafale for logging these flying hours. Also there is the added advantage of not being included in f16 threat library western platforms are also nato platforms and voila this is the best for us. They have now become comfortable and used to the thinking under UPA that these politicians will never authorise a war on pakistan, so it is meaningless to think about quantity of aircraft because it will never be used in battle anyways so let us just live our everyday lives better and safer.


You open BRF hoping to see some good discussion but it never surprises to live up to expectation!

^^^The kind of thankless idiots which pilots from all streams have died defending since 1947..........

rohitvats
BR Mainsite Crew
Posts: 7726
Joined: 08 Sep 2005 18:24
Location: Jatland

Re: Airborne Early Warning & Control: News & Discussion

Postby rohitvats » 06 Jan 2020 15:42

vivek_ahuja wrote:
“The need for more AWACS was acutely felt post the Balakot air strike, with Pakistan being able to deploy its SAAB AWACS 24x7 in the north and south sectors and India being able to cover the two theatres only for 12 hours each day,” one of the officials cited above said.


A good example of how in the near future, we are going to get swamped by lower level Pak and Chinese tech while our "gold-plated" assets struggle to plug gaping holes because of their extremely limited numbers.

<SNIP>


Can we please parse the above statement as to how PAF is able to maintain 24 x 7 coverage in North and South with 4 x SAAB AEW&C systems?

What is the time-on-station for each SAAB AEW&C? As per an article by Center for Air Power Studies (CAPS), India would require 20 x AWACS to ensure it can maintain 4 x AWACS in air for 24 x 7 surveillance. And this will also happen during peak operation time. No country, except USA, can maintain 24 x 7 AWACS led air surveillance.

So, it is most likely that with 4 x SAAB AEW&C, PAF can maintain 24 x 7 surveillance in ONE sector . And this too assuming its has 100% aircraft availability. Further, this kind of geographic dedication of resources will happen only in case of operation like Swift Retort. Otherwise, those AEW&C will be providing coverage over an area for specific period of time. Pakistan will not commit such resources only in a specific sector and leave rest of the country disadvantaged.

Yes, one can argue that second sector will be covered by Chinese AEW&C systems. But how good these are, is open for debate. Further, we have the issue of these being able to talk to other assets on ground and on air.

In case of a full blown shooting match, these 4 + 4 AEW&C system would be spread across 3 to 4 nodes. These could be as follows:

1. Islamabad - Lahore - Multan - This is the heart of Pakistan and home to their prime assets - both within the army, air force and strategic forces. Not to forget that Multan - Bahawalpur - Fort Abbas - Bahawalnagar quadrilateral is going to be scene of intense ground war.

2. RYK - Sukkur (Central Pakistan) - Again, this is going to be battleground for intense ground operations. PAF has developed air bases in this region to provide better coverage.

3. Hyderabad - Karachi: Land operations and Naval Operations.

1st node itself will consume the 4 x SAAB AEW&C systems. And they will be stretched further if multiple SAAB AEW&C are required to be in air simultaneously. A Phalcon can most probably manage 2x or 3x of the workload/battlespace management as compared to SAAB.

PAF will most likely try to manage everything south of 1st node with Chinese airplanes.

While PAF seems to have done OK, lets not overplay the hand.

nam
BRF Oldie
Posts: 3570
Joined: 05 Jan 2017 20:48

Re: Airborne Early Warning & Control: News & Discussion

Postby nam » 06 Jan 2020 15:49

In terms of radar at higher altitude, which a aerostat provides, we should actually consider deploying a high powered radar in one of the J&K region at say.. 17000 feet!

If we can create a engineering marvel in Siachien... at 20k feet.. even better :D

A radar which looks along the length of Pak, deployed at those height will have fabulous advantage. J&K, Ladakh is a great place for ABM radars...

rohitvats
BR Mainsite Crew
Posts: 7726
Joined: 08 Sep 2005 18:24
Location: Jatland

Re: Airborne Early Warning & Control: News & Discussion

Postby rohitvats » 06 Jan 2020 16:05

vivek_ahuja wrote:<SNIP>On Feb 27, everyone was in surge mode and all assets were in the air. That is where the IAF AEW coverage deficiency became glaringly visible.<SNIP>


And how did the lack of AWACS or AEW&C impact the outcome of the air battle?

By all accounts, the PAF strike package was detected the moment various aircraft took off from their respective bases. And the air battle over Kashmir was handled by a lady fighter controller sitting in Barnala, Punjab.

How would've presence of AWACS altered the outcome on 27th February?

Both countries have decent surveillance capability with Indian radar network now becoming increasingly dense and much more modern than what PAF has in its inventory, save for long range AN/TPS-77. We now have radars across all levels and most of them are state of art with still more modern radars expected to enter in service over next 2-3 years.

The real strength of AWACS lies in battle space management and managing large force engagements. Like how PAF did on 27th February. And like how IAF intends to use its AWACS. Surveillance is just one of the roles. Further, please don't forget that in Kashmir sector, PA/PAF don't have good surveillance assets - notwithstanding they moving out their MPDR-45/90 radars. That is another reason they needed SAAB AEW&C system in the air.

rohitvats
BR Mainsite Crew
Posts: 7726
Joined: 08 Sep 2005 18:24
Location: Jatland

Re: Airborne Early Warning & Control: News & Discussion

Postby rohitvats » 06 Jan 2020 16:07

nam wrote:In terms of radar at higher altitude, which a aerostat provides, we should actually consider deploying a high powered radar in one of the J&K region at say.. 17000 feet! If we can create a engineering marvel in Siachien... at 20k feet.. even better :D A radar which looks along the length of Pak, deployed at those height will have fabulous advantage. J&K, Ladakh is a great place for ABM radars...


We already have medium power radars sited on top of mountain(s) to look deep into Pakistan.

nam
BRF Oldie
Posts: 3570
Joined: 05 Jan 2017 20:48

Re: Airborne Early Warning & Control: News & Discussion

Postby nam » 06 Jan 2020 16:16

rohitvats wrote:
nam wrote:In terms of radar at higher altitude, which a aerostat provides, we should actually consider deploying a high powered radar in one of the J&K region at say.. 17000 feet! If we can create a engineering marvel in Siachien... at 20k feet.. even better :D A radar which looks along the length of Pak, deployed at those height will have fabulous advantage. J&K, Ladakh is a great place for ABM radars...


We already have medium power radars sited on top of mountain(s) to look deep into Pakistan.


Good to know. I guess some of the HPR will go in this region. That will be a tremendous boost.

nam
BRF Oldie
Posts: 3570
Joined: 05 Jan 2017 20:48

Re: Airborne Early Warning & Control: News & Discussion

Postby nam » 06 Jan 2020 16:30

Our Netra is a S band radar. Able to monitor 300KM airspace. With A330 if we manage a similar S band and ability to monitor 600-700KM that is a phenomenal capability.

It obviously allows larger coverage, however A330 AWACS being jet powered can move in a new sector much faster. Not to mention the fact that AESA allows longer sector specific scan. Netra's regular 300KM becomes 400KM+ in sector specific scan! Wedgetail has a better antenna design, so A330 will be restricted on how fast it can go.

There is lot of advantages of having a jet based, 360 degree AWACS. A320 like platform would be cheaper, but then you have to spend money on buying additional tanker. Cheaper to go for A330.

Pak's 240 degree, propellers is all fine for restricted fights and peace time. In wartime their 240 is a handicap in battle space management. You have to fly a specific pattern, putting it closer to adversary fighters.

Increasingly our ground radars, SAM & AWACS are Indian. With S band A330 should be able to cue ground based SAM towards incoming targets in the future. Just like Mf-Star, a S band radar does. All these allows of a level of integration, PAF can only dream off..

Karan M
Forum Moderator
Posts: 19508
Joined: 19 Mar 2010 00:58

Re: Airborne Early Warning & Control: News & Discussion

Postby Karan M » 06 Jan 2020 17:34

rohitvats wrote:The real strength of AWACS lies in battle space management and managing large force engagements. Like how PAF did on 27th February. And like how IAF intends to use its AWACS. Surveillance is just one of the roles. Further, please don't forget that in Kashmir sector, PA/PAF don't have good surveillance assets - notwithstanding they moving out their MPDR-45/90 radars. That is another reason they needed SAAB AEW&C system in the air.


The main advantage of airborne radars is the line of sight one. In mountainous regions in particular, even radars sited on mountain tops can't always look down into parallel valleys or paths of ingress. A high flying radar OTOH can do so. In short, AWACS proceeding with formations can detect and forewarn high flying aircraft against ambushes.

rohitvats
BR Mainsite Crew
Posts: 7726
Joined: 08 Sep 2005 18:24
Location: Jatland

Re: Airborne Early Warning & Control: News & Discussion

Postby rohitvats » 06 Jan 2020 18:44

^^^Agreed.

abhik
BRF Oldie
Posts: 2833
Joined: 02 Feb 2009 17:42

Re: Airborne Early Warning & Control: News & Discussion

Postby abhik » 06 Jan 2020 19:37

@brar_w IIRC DARPA was working on a stratospheric rigid hull air ship - anything come out of it?
Link from DARPA site (although not 100% sure it was this one or another project):
https://www.darpa.mil/program/integrate ... -structure

vivek_ahuja
BRF Oldie
Posts: 2223
Joined: 07 Feb 2007 16:58

Re: Airborne Early Warning & Control: News & Discussion

Postby vivek_ahuja » 06 Jan 2020 20:18

rohitvats wrote:And how did the lack of AWACS or AEW&C impact the outcome of the air battle?


You mean the one battle that has happened when our AEW airplane was on station and waiting? Come on. I find this kind of argument to be a non-sequitur and worse, it misses the main point of the posts above: we do not have enough airplanes to do the job on a 24x7 basis for just two critical sectors (not the whole border) that would be required in a real war. This battle of Feb 27 (and more importantly the aftermath of it with lots of surge CAP missions from both sides) was a giant red flag for the IAF that revealed the shortage of AEW/AWACS numbers.

It does not matter how good or amazing the desi AEW is compared to the Paki one when the Paki ones are able to stay in the air while yours are on the ground or in another sector. The MoD and IAF officials have stated how they could maintain only half as much coverage as was needed. With almost 11 AEW airplanes, the PAF did not have the coverage problem on those days.

Also, we are not referring to the entire border at all times. But if the coverage cannot be maintained for the entire border at all times, perhaps a decision needs to be made as to how many sectors the IAF wants covered at any time. Are we okay with covering one sector and leaving others at the mercy of static ground radars?

So, it is most likely that with 4 x SAAB AEW&C, PAF can maintain 24 x 7 surveillance in ONE sector . And this too assuming its has 100% aircraft availability.


I think you need the read the posts I made earlier in more detail. The entire analysis converts these into numbers that we can use for comparison. At the moment, the PAF can maintain 24x7 coverage in two or more sectors. The IAF can do two sectors for 12x7 hours, by its own admission.

Also, the PAF now has 6 (and possibly 7) SAAB AEW, not 4. See my post in the Pak mil thread about this. Add 4 of the Chinese numbers to this. All of these have higher endurance to the Embraer AEW on account of the propulsion systems that I have also discussed. Higher endurance on station (without soaking up the limited tankers) is a force multiplier for the Pakis.

brar_w
BRF Oldie
Posts: 8756
Joined: 11 Aug 2016 06:14

Re: Airborne Early Warning & Control: News & Discussion

Postby brar_w » 06 Jan 2020 21:23

nam wrote:There is lot of advantages of having a jet based, 360 degree AWACS. A320 like platform would be cheaper, but then you have to spend money on buying additional tanker. Cheaper to go for A330.
.


You can get very good TOS and performance from the 737/320 sized aircraft if you built around it like Boeing and Northrop Grumman did with the E-7. But there, the top-hat configuration, and sensor frequency was chosen to match that and to provide a low drag solution that could make the *pocket AWACS* go out and do a vast majority of the missions the big AWACS used to do. The sensor was purposed built (*sort of* though it was purpose built for a different but very similar reason) to allow for that as the Australians wanted a platform that was lower cost to buy and operate, could take off and land from a wider selection of runways yet still go out and perform missions that the E-3 was expected to perform without compromising a whole lot on vital performance metrics.

RAAF crews have been routinely getting 14-15 hours of airborne time with one refueling only and have managed to get 17+ hours with two. This is not very different from the E-3 which can get anywhere from 7.5-9 hours without a tanker hit depending upon the mission and altitudes it is flying. That is a lot given the fact that in the context of the IAF the route to the desired orbit would be quite small. I don't know from the top of my head what the longest duration AWACS mission has been but if I'd guess that most desirable long range platforms for the said mission would be in the 7-9 hour un-refueled class which you can probably meet with either an A320/737 sized aircraft or a larger A330/767 sized platform as long as you optimize the overall platform for that performance (as was done on the E-7).

However, with an S-band chappati configuration a hypothetical 737/320 sized aircraft would be compromised given the aerodynamics and probably also the power generation payload onboard and its associated weight and volume. What would be interesting to see is the TOS with and without refueling that the A330 gets with that radar configuration. If I were to venture a guess, I'd guess it too would require at least 1 refueling for a 15 hour mission much like the E-7 and the E-3. I therefore agree with the A-330 decision. Time to get this contract signed and for the parties involved to get on with it. A full up AEW EMD program generally takes about a decade to bring about so they should be targeting a 2028-2032 timeframe for operational capability of this program...but for this they need all the contracts signed in the next few months.
Last edited by brar_w on 06 Jan 2020 21:44, edited 1 time in total.

nam
BRF Oldie
Posts: 3570
Joined: 05 Jan 2017 20:48

Re: Airborne Early Warning & Control: News & Discussion

Postby nam » 06 Jan 2020 21:43

The only silver lining in this saga is that DRDO already has the radar and radome ready.

I would hazard a guess that it will take 3 years for aircraft modification and install. Another 3 years for testing. So this kit not coming before 2026.

Airbus had also offered a similar configuration to UK. So I am hoping they have done the studies required and reduce the time required.


But then our next fight with Pak is not going to wait for 6 years...
Last edited by nam on 06 Jan 2020 21:47, edited 3 times in total.


Return to “Military Issues & History Forum”

Who is online

Users browsing this forum: pravula, Sanju and 45 guests