AWACS Performance in electronic warfare environment?

[Todjaeger]

ESA vs. radome

Going in a different direction, but related to "Best AEW&C"... I'd rather this not degenerate into a "size" contest...

What are the advantages and disadvantages of Electronically Scanned Arrays and radome-based AEW&C radars. Which of the two technologies is better overall, or in specific areas? i.e. does one type of technology generally have longer range than the other, is one more or less sensitive to ground clutter, etc.

If it can be determined which type of AEW&C (ESA or radome) is generally better, then it might be possible to estimate which AEW&C program that is currently running is the "best"... As a general rule I have to agree with what Totoro wrote.

As far as working in high jamming, high clutter electronic enviroment, rule of thumb is that newer is better, due to software/hardware.

GF, I'd be very interested in your thoughts (those that you can or feel comfortable relating...) on radome vs. ESA

 

[knightrider4]

Mesa

From what I understand its main advantage is that the mesa's scan and update rates are much quiicker than a mechanical array. It is also less maintenance intensive than a mechanical array ie; no bearings to wear out. It also has the benefit of being able to scan a sector at twice the nominal range of what would normally be covered at 360 degrees.

 

[gf0012-aust]

From what I understand its main advantage is that the mesa's scan and update rates are much quiicker than a mechanical array. It is also less maintenance intensive than a mechanical array ie; no bearings to wear out. It also has the benefit of being able to scan a sector at twice the nominal range of what would normally be covered at 360 degrees.

basically correct.

its also complicated by the type of ESA config, eg some beam models don't have any forward or rearward scanners, so the primary ESA is more or less a butterfly config. the only way to deal with the blind spot is to either weave then plane in and out - or take the phalcon approach (which is actually a legacy USAF design) and place a forward scanner in the nose.

MESA is different again as it does actually have arrays in the bow and stern of the beam as well as the flanks. so its an autonomous 360 scan, but with less power forward or rearward.

 

[gf0012-aust]

GF, I'd be very interested in your thoughts (those that you can or feel comfortable relating...) on radome vs. ESA

I'll see if I can drag up one of the Ewarfare guys, I'm still a member of AOC but there are others in here who are far more qualified, I'm more of a generalist.

For instance there's one Ewarfare bloke in here who prefers analogue over digital, whereas the "new turks" would probably yell louder for any derivative of ESA, be it PESA, MESA etc etc...

 

[Totoro]

gf0012, i don't mean to go off topic too much and would love to PM you but am not allowed to. Says I don't have permission to acces send PM page. Who should i contact about that issue?

As far as ESA versus mechanical scanned arrays, It would appear that general shift is towards ESA. I do believe USAF, too, said the modernization of E3 will include an ESA inside of the radome. Other planes too have 'conventional' radomes but with ESAs inside, like A-50I/E or KJ-2000.

While both arrays should in theory have same max range, due to steering of the beam on ESAs its range/resolution starts to somewhat degrade due to changed beam. That is why in many articles it is mentioned that anything over 60 deg off bore is of little use in ESAs. Basically it makes the beam half as big at 60 deg.

Thing is, one doesn't really need huge ranges in most situations. Or, sure, its good to have them but when you can get at least half the range and most of the time even more than that, in return for other benefits - ESA seems more effective.

Depending on frequency and wave length, both can be sensitive or not sensitive enough to ground clutter. Beyond freq./wavelength its all in the software/hardware as far as various filtering and resolution sharpening is concerned.

In addition to that, ESAs provide greater reliability, much faster scanning, more tracked targets.
They're more expensive and the whole system requires more power. When adding active ESA, it further increases size and weight as it needs additional cooling. It does offer even better multitasking and a vast increase in number of tracked targets.

 

[gf0012-aust]

gf0012, i don't mean to go off topic too much and would love to PM you but am not allowed to. Says I don't have permission to acces send PM page. Who should i contact about that issue?

probably due to the fact that web implemented a "wait and see" limit on new members. that was originally designed to stop spammers who were PMing everyone as soon as they joined.

you can get me on schitt.magnet at gmail dot com. make sure you put your name in the subject line so that the filter doesn't boot you straight into the delete bin.

I'll then send you my real email addy.

gf

 

[chrisrobsoar]

Most important difference would be in higher altitude offering greater radar horizon range. Helicopters flying up to 5 km would see low flying targets maybe 250 km away while awacs at 10 km would have a theoretical reach of some 430 km for same targets.

Other than that, i dunno, it depends on the helicopter, how big it is, how big of an array can it carry, how much space for equipment and operators there is, how much el. power can its engines offer, etc. Given the mentioned speed/flight endurance time advantage planes have, helicopters really seem to be only a last ditch resort, when plane based awacs are not available.

I agree, but there is a an error in your calculation of the radar horizon.

Radar altitude 5km 10km 15km
Max Range 250km 352km 430km

Aircraft usually operate at an altitude of 8-12km depending on the maximum peak power of the radar.

Chris

 

[Totoro]

Actually we are both a little wrong. I was using those figures off the top of my head, but now i calculated precisely using the "range in nm=1.23 (second root of altitude in feet)" equation, where 1.23 is constant taking into account the fact radio waves propagate differently through atmosphere and got these numbers:

3 km - 226 km
5km - 291 km
10 km - 412 km
15 km - 505 km
20 km - 583 km

I included 3 km altitude cause it is actually more appropriate for helicopters, 5km is a bit hard for any heli to reach they're full of fuel and payload.

 

[swerve]

Going through my books I came across the following sources which might make selection a bit easier, or allow for more concise debate.

Here goes the list of AEW&C:
Beriev A-50 Mainstay with Vega-M Shmell-II radome
Beriev A-50 Mainstary with IAI Phalcon ESA
Boeing E-3 Sentry AWACS with Northrup Grumman AN/APY-2 radome
Boeing E-767 AWACS with Northrup Grumman AN/APY-2 radome
Boeing 737-700 Wedgetail AEW&C with Northrup Grumman MESA
Embraer EMB-145SA with Ericsson Erieye ESA
Boeing 707-320C Phalcon with IAI Phalcon ESA
Lockheed Martin EC-130H/J Hercules with LM AN/APS-145 radome
Northrup Grumman E-2C Hawkeye AWACS with LM AN/APS-145 radome
Saab 340B (S100B Argus) AEW&C with Ericsson Erieye ESA

You can add Saab 2000 with Ericsson Erieye ESA (not yet built) & Gulfstream G550 with IAI Phalcon ESA (delivered, working up to IOC) to that list, as well as Chinese projects.

 

[boldeagle]

KA-31 and Y-8 with "Balance Beam"

As I look at the thumbnail pic of the Russian KA-31 (posted by another correspondent, earlier), I note that the suspended radar on that helo reminds me of the "Balance Beam" radar on the Red Chinese Y-8. Am I correct that there is a relationship between the two?

 

[Totoro]

There shouldn't be any relationship, other than that both are phased arrays. Ka-31 entered service in 1995, if i'm not mistaken. While certainly possible that IF russian help was provided in chinese balance beam radar projects, that same people working on ka-31's radar helped chinese radar too... it's a stretch. There are plenty of other phased arrays in russia that chinese might have used as starting base, if they used any at all. Physically, beam itself is a virtual copy of ericsson's array on erieye system. External appearance isn't that similar to ka-31's "Oko/Eye" array.

 

[tphuang]

There shouldn't be any relationship, other than that both are phased arrays. Ka-31 entered service in 1995, if i'm not mistaken. While certainly possible that IF russian help was provided in chinese balance beam radar projects, that same people working on ka-31's radar helped chinese radar too... it's a stretch. There are plenty of other phased arrays in russia that chinese might have used as starting base, if they used any at all. Physically, beam itself is a virtual copy of ericsson's array on erieye system. External appearance isn't that similar to ka-31's "Oko/Eye" array.

did a little googling, looks like ka-31 first appeared in 1988.
As for copying from the Russians, I just can't think of any Russian AESA radar that China can possibly copy off.

To gf, I was wondering if you can comment on export versions of E-3/767 vs domestic versions. How much are the export versions downgraded from domestic versions (if at all?). And also, the South Korean air force seemed to favour Phalcon over Boeing 737 before Phalcon got disqualified. Aside from the price advantage of Phalcon, what else does it actually have over Boeing?

 

[gf0012-aust]

To gf, I was wondering if you can comment on export versions of E-3/767 vs domestic versions. How much are the export versions downgraded from domestic versions (if at all?).

Export versions are always downgraded from the host countries own capability. In the case of wedgetail its slightly different in the sense that it required some specific australian input rather than the base package. although other countries are getting a MESA look alike, they certainly won't be getting wedgetail per se.

And also, the South Korean air force seemed to favour Phalcon over Boeing 737 before Phalcon got disqualified. Aside from the price advantage of Phalcon, what else does it actually have over Boeing?

I was always under the clear impression that wedgetail was favoured over phalcon as it is regarded as having a far more complex and capable overall suite (plus later generations of ESA technology).

notionally - and I stress notionally one could argue that phalcon is better suited to leading an offensive strike package. in that sense, I'd argue that it was not going to be in favour due to local doctrine conflict issues.

 

[Todjaeger]

Checking a new book I just purchased, I realised we've been making a mistake... For the IAI, Phalcon isn't a radar, it's a system, much like AWACS is a USAF project that led to the E-3 system. The radar itself is the Elta EL/2075 phased-array radar.

In the Phalcon system, the solid-state radar is located in a bulbous nose as well as in a pair of cheek panniers and one emitter in the tail. This provides all-around coverage, and the steerable beams can scan area in approximately 1/10th the time a rotodome-equipped AEW can.

Incidentally, how does the Wedgetail get around the blindspots caused by the airframe? All the pictures I've seen show the "canoe" fairing above the fuselage, but the wings and tail will cause gaps in what can be scanned in different directions. Are there additional arrays mounted aboard the Wedgetail? I haven't noticed any panniers that could be radar equipped?

-cheers

 

[gf0012-aust]

Checking a new book I just purchased, I realised we've been making a mistake... For the IAI, Phalcon isn't a radar, it's a system, much like AWACS is a USAF project that led to the E-3 system. The radar itself is the Elta EL/2075 phased-array radar.

In the Phalcon system, the solid-state radar is located in a bulbous nose as well as in a pair of cheek panniers and one emitter in the tail. This provides all-around coverage, and the steerable beams can scan area in approximately 1/10th the time a rotodome-equipped AEW can.

The phalcon is almost a direct copy of an earlier US design - in fact they're identical in appearance. The US abandoned the phalcon bulbous nose profile and pursued a different design.

The phalcon design is why I alluded to a better strike leader role... rather than a race track runner

txt deleted

 

[Todjaeger]

The phalcon is almost a direct copy of an earlier US design - in fact they're identical in appearance. The US abandoned the phalcon bulbous nose profile and pursued a different design.

I was unaware of any early US solid-state AEW program, I'll have to pick a relative's brain to see if he remembers anything about it. GF, do you know what the name of the design/project was that was abandoned, or the reason for it? I'd be curious to know.

Also, I have a question about the following.

For instance there's one Ewarfare bloke in here who prefers analogue over digital, whereas the "new turks" would probably yell louder for any derivative of ESA, be it PESA, MESA etc etc...

Granted, it's been awhile since the difference of analogue vs. digital was explained, and in my field it's somewhat different (at least in terms of apps). As I understand it, analogue signal is a continous wave, whereas digital signal is a series of samples transmitted and then re-assembled to resemble a wave. With analogue a "true picture" of the signal is transmitted but (at least with what I do) the signal can be vulnerable to interference. With digital, because it is supposed to be an approximation of the wave, the lower the sample rate, the worse it resembles an actual wave, and the higher the sample rate, the better. The other area of difference is that with digital, there can be built in error correction, which can help counter interference.

What I'm not sure about is the difference in radar for analogue vs. digital. If someone could explain it to me, or if there's a link/book, etc. I'd appreciate it.
:unknown

 

[gf0012-aust]

I was unaware of any early US solid-state AEW program, I'll have to pick a relative's brain to see if he remembers anything about it. GF, do you know what the name of the design/project was that was abandoned, or the reason for it? I'd be curious to know.

One of the ex Fighter forum guys might remember as there was a post which was based on ugly aircraft separated at birth.

the winner was a nimrod with a nose wart followed by the US aircraft with equal place followed by the phalcon as it was seen as a clone of the US platform.

some clown referred to the US aircraft/Phalcon as being afflicted with Herpes.

 

[Todjaeger]

One of the ex Fighter forum guys might remember as there was a post which was based on ugly aircraft separated at birth.

the winner was a nimrod with a nose wart followed by the US aircraft with equal place followed by the phalcon as it was seen as a clone of the US platform.

some clown referred to the US aircraft/Phalcon as being afflicted with Herpes.

nfloorl:
I'll have to search to see if I can find some pics. I've got different Nimrod pics (how aptly it's named given appearance) and some Phalcon pics. I'll have to see what I can dredge up for USAF...

-cheers

 

[birdofprey]

AWACS vs AEW&CA

the most likely Scenario we can see AWACS and AEW&CA operating in both sides in an actual combat would be in indo-pak. india purchased 3 phalcons while pakistan 6 Erieye and are to be inducted by 2008-9.
please elaborate your comments on who would make the most use out of there platforms in an actual combat...

 

[kams]

nfloorl:
I'll have to search to see if I can find some pics. I've got different Nimrod pics (how aptly it's named given appearance) and some Phalcon pics. I'll have to see what I can dredge up for USAF...

-cheers

Plenty of pictures of all kind of AEW platforms here.

AEW/C