F-35 vs Su-30/35

The F-35 compared with other modern jets.
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sergei

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Unread post29 Mar 2015, 14:07

"Su-35 can hardly see stealth F-35 from more than 20 km ( in jamming condition)"
Will see at 50km in infrared.
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basher54321

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Unread post29 Mar 2015, 15:13

sergei wrote:Will see at 50km in infrared.


My eyes saw that one coming at least 1000000 miles away. :D
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shrimpman

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Unread post29 Mar 2015, 16:21

eloise wrote:the thing is you are on an American forum, so if you cant properly explain your idea in English , it only bad for you because most people here ( i think 99%) use English
many spelling and grammar mistakes in your post can be fixed if you spend only 5-6 seconds, putting your post into Google Translate before submitting it ( that will be better for you and everyone else )


Please don't go this way. We, the non-English types, are trying our best. Personally, as a Polish living in Ireland, I think this is really unfair when people say this kind of things to me. It is extremely frustrating to speak five languages and be told by a monoglote native that I should learn more. Come on, Eloise, beat them with arguments, not with groin kicks ;)

Can you guys please help me understand one thing (I know nothing about RCS). If F-35 is carrying external stores, it loses its stealth because the launchers and weapons can be seen. I get that. But RCS of 2 AMRAAMs cannot possibly be detected THAT easily from a distance? I mean a non-stealthy 10m2 RCS plane would be detected far earlier than a stealthy one with some visible weapons? When I read your comments it looks like "heavy" F-35 can be seen from halfway round the globe. Is there something I am missing?
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eloise

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Unread post29 Mar 2015, 16:56

sergei wrote:"Su-35 can hardly see stealth F-35 from more than 20 km ( in jamming condition)"
Will see at 50km in infrared.

hmm, fair enough, but i think F-35 pilot can fly near or in cloud to reduce enemy's IRST effectiveness
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Unread post29 Mar 2015, 16:59

shrimpman wrote:
Can you guys please help me understand one thing (I know nothing about RCS). If F-35 is carrying external stores, it loses its stealth because the launchers and weapons can be seen. I get that. But RCS of 2 AMRAAMs cannot possibly be detected THAT easily from a distance? I mean a non-stealthy 10m2 RCS plane would be detected far earlier than a stealthy one with some visible weapons? When I read your comments it looks like "heavy" F-35 can be seen from halfway round the globe. Is there something I am missing?


You would still expect the RCS to still be vastly reduced compared to a conventional aircraft like the Su-35 with pylons and missiles.

The estimations of range with RCS/IR are usually based on what aircraft you are arguing for and normally take no account of actual limitations or scenarios. 8)
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eloise

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Unread post29 Mar 2015, 17:05

shrimpman wrote: Please don't go this way. We, the non-English types, are trying our best. Personally, as a Polish living in Ireland, I think this is really unfair when people say this kind of things to me. It is extremely frustrating to speak five languages and be told by a monoglote native that I should learn more. Come on, Eloise, beat them with arguments, not with groin kicks ;)

alright my bad, actually English is not my mother tongue either
shrimpman wrote:

Can you guys please help me understand one thing (I know nothing about RCS). If F-35 is carrying external stores, it loses its stealth because the launchers and weapons can be seen. I get that. But RCS of 2 AMRAAMs cannot possibly be detected THAT easily from a distance? I mean a non-stealthy 10m2 RCS plane would be detected far earlier than a stealthy one with some visible weapons? When I read your comments it looks like "heavy" F-35 can be seen from halfway round the globe. Is there something I am missing?

RCS are a little bit different from visual
if object A have RCS = 1 m2
object B have RCS = 2 m2
that doesn't mean they will have RCS = 3 m2 when they are together, their RCS could be alot more due to the reflecting radar wave between 2 object ( create a conner reflector)
in the F-35 case, the pylon make a 90 degree angle with the wing, missiles fins are also perpendicular ( perpendicular surface have huge RCS)

body_corner_reflector_ex..png

body_corner_reflector_ex.png
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sergei

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Unread post29 Mar 2015, 17:41

basher54321 wrote:
sergei wrote:Will see at 50km in infrared.


My eyes saw that one coming at least 1000000 miles away. :D

My ears have heard the sound of keys on your keyboard earlier than you start typing it :D
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Unread post29 Mar 2015, 21:14

sergei wrote:zero-one
weapons:
4xR-77: 1540 lbs
2xR-11:

R-11 Soviet tactical ballistic missile.

https://en.wikipedia.org/wiki/R-11_Zemlya

:bang:

F-35 destroyed by a nuclear explosion, Su-30 win.



Slight mistype. You know very well that what I meant was the AA-11 archer, and it doesnt change the fact that the F-35A has better thrust - weight ratio stats and equal wing loading stats once body lift and tail lift is taken into account.
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Unread post29 Mar 2015, 23:26

sergei wrote:"Su-35 can hardly see stealth F-35 from more than 20 km ( in jamming condition)"
Will see at 50km in infrared.


The main problem with that is that it might know that "something" is in that direction, but it will not know if it's a fighter at 25km, an AWACS at 200km, or soemthing else at 2000km.

Without the ability to determine range, no tracking and more importantly no weapons, can be used.
"The early bird gets the worm but the second mouse gets the cheese."
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Unread post30 Mar 2015, 12:29

I think AN/APG-81 range performance is severely underestimated by most people and it most probably equals or outperforms even Irbis-E rangewise and is otherwise far superior radar system. This is my reasoning for this:

AWG-9 and AN/APG-67 range performance is well known. Both use slotted planar array antenna and TWT transmitters and have otherwise similar construction. AN/APG-73 also has very similar construction and it also sits directly between these two radars. AWG-9 had detection range of 213 km and tracking range of 167 km against 5 square meter RCS target. AN/APG-67 had a detection range of about 90 km and tracking range of about 70 km against same target. As AN/APG-73 (of late Classic Hornets and early Super Hornets) is directly between the two, it should have a detection range of about 150 km and tracking range of about 115-120 km against that same target. This performance is very likely as Swedish sources claim Ericsson PS-05/A radar for JAS Gripen can detect that kind of target 120 km away. PS-05/A has quite a bit smaller antenna than AN/APG-73 and thus will have shorter range as the two have very similar construction otherwise. Russians claim their Phazotron Zhuk-ME also has similar detection performance as PS-05/A and it also has very similar construction and smaller antenna to AN/APG-73.

Why did I mention AN/APG-73 and all those old radars? Because USN claims that AN/APG-79 for Super Hornet has two to three times the detection range of the earlier AN/APG-73. Same claims have been made by a number of airforces taking AESA radars into service, so it’s very likely true. This would mean AN/APG-79 can detect that 5 square meter target out somewhere between 300 and 450 km away and track it between 240 and 360 km away. Now AN/APG-81 has larger antenna with much higher T/R module count meaning it has superior output power and antenna gain. My estimate would give it about 1/3 longer range without any other improvements. That would give it detection range of about 400 to 600 km against that same target. Of course AN/APG-81 is about a decade newer implementing much newer technology, including new T/R modules. So it likely has even bigger advantage than that due to each T/R module having higher output power and lower losses.

Now another angle: http://www.acq.osd.mil/dsb/reports/ADA391893.pdf

This is a report paper made 15 years ago by US Secretary of Defense Office Defense Science Board and they should really know their stuff about technology. They predicted then that a very conservative estimate for ground surveillance optimized AESA radar with average power output of 2.5 to 4.5 kW would give a detection range of about 230 km against 3 square meter target and a cued search (smaller search area) range of about 300 km. Now they used extremely conservative technology assumption of 15 percent efficiency for the modules and about 10W peak power in each module. Modern T/R modules have efficiencies at least twice that and 40-50 percent efficiency is pretty standard with much more powerful (15W to 25W) modules readily available. This along with higher module efficiency would mean that those earlier figures for APG-79 and APG-81 are very believable as even the APG-79 should easily have at least equal and likely significantly superior average power. APG-81 likely has a lot more average power available.

I believe Russian figures for Irbis-E and their other radars as they are achievable. Irbis-E is said to be able to detect 3 square meter target 350 to 400 km away within 100 square degree search area (which is very small search area). This means normal search mode detection range is likely about 230 to 270 km against that same 3 m^2 target depending on many variables. Those figures are because cued search usually has at least 50 percent longer range than normal search. Cued search is useful for targets which have been quite accurately detected by other sensors and is not that good for searching due to small search area.

Calculating all of the above together, we can estimate the following range performance against different RCS targets (numbers are rounded somewhat):

Irbis-E
0.0001 m^2: cued search 30 km, normal search: 20 km
0.001 m^2: cued 50 km, normal 35 km
0.01 m^2: cued 90 km, normal 60 km
0.1 m^2: cued 160 km, normal 115 km
1 m^2: cued 300 km, normal 200 km
10 m^2: cued 500 km, normal 350 km

AN/APG-79:
0.0001 m^2: cued search 32 km, normal search: 23 km
0.001 m^2: cued 55 km, normal 40 km
0.01 m^2: cued 100 km, normal 75 km
0.1 m^2: cued 180 km, normal 135 km
1 m^2: cued 330 km, normal 250 km
10 m^2: cued 600 km, normal 450 km

AN/APG-81 (conservative estimate):
0.0001 m^2: cued search 40 km, normal search: 30 km
0.001 m^2: cued 60 km, normal 40 km
0.01 m^2: cued 125 km, normal 85 km
0.1 m^2: cued 220 km, normal 150 km
1 m^2: cued 450 km, normal 300 km
10 m^2: cued 750 km, normal 500 km

This only shows that 4th gen fighters will be detected by all of these fighters at very long ranges with ease. Even most advanced 4th gen fighters would be detected quite a long distance away. It also shows that AN/APG-81 will detect Su-35S at far longer distances than Su-35S is capable of detecting F-35. This also shows that even Super Hornet very likely has quite significant detection/tracking advantages against Su-35. Even if we take the lowest end numbers for APG-81 (for example T/R modules which have been available for over 15 years for US radar manufacturers), it still likely has at least equal range performance to Irbis-E. These numbers also show that Irbis-E has the advantage against all current non-AESA radars.

Comparing F-35 and any 4th gen fighter, including Su-35, in EW environment would not be pretty for any of those 4th gen fighters. Su-35 does have EW system in KNIRTI SAP 518. Problem is that it’s a sector jamming system. Those kinds of jammers can jam certain frequency or frequencies forward or aft section of the aircraft. The difference between F-35 EW system is that using APG-81, F-35 can concentrate the jamming power precisely towards the enemy emitter. End result is that enemy radar receives much more powerful jamming signal compared to conventional self protection jammer systems. In more technical terms, conventional jammer systems have very low gain antennas as they transmit a wide beam to cover the whole sector at once. They lack the capability to accurately target the enemy radar and thus most of their radiated power is wasted. Facing off against each other, F-35 will have much lower radar cross section, at least as powerful radar and much more powerful jamming system. Even as F-35 uses part of the radar as a jammer, it won’t severely affect the radar performance as only small fraction of the modules would be needed for jamming duty.

I'm not trying to paint Flankers as bad fighters, definitely not. I'm just illustrating what advantages F-35 will have against all 4th gen fighters, no matter how much they are upgraded.
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Unread post30 Mar 2015, 13:49

sergei wrote:zero-one
------------
1. They may be the target of the incoming AMRAAMs and take evasive maneuvers as well
2. Heavy ECM employed by the F-35s limit their participation at those ranges
3. They do not have LPI capable data links.
--------------
1. F35 dont have Long-range missiles, 2 wave Su-35 to far away for Aim 120.
2.You cant jumm at range more then range your can see(if there is no pod)
3. Do they need it ?


2. Yes you can jam at ranges far longer than you yourself can see. For jamming you only need to receive enemy transmitted signal to know where enemy radar is and then you can send your own signals back. You don't need to see the enemy to be able to jam its radar. This applies to podded or not podded EW systems.
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Unread post30 Mar 2015, 14:36

hornetfinn wrote:

Why did I mention AN/APG-73 and all those old radars? Because USN claims that AN/APG-79 for Super Hornet has two to three times the detection range of the earlier AN/APG-73. Same claims have been made by a number of airforces taking AESA radars into service, so it’s very likely true. This would mean AN/APG-79 can detect that 5 square meter target out somewhere between 300 and 450 km away and track it between 240 and 360 km away. Now AN/APG-81 has larger antenna with much higher T/R module count meaning it has superior output power and antenna gain. My estimate would give it about 1/3 longer range without any other improvements. That would give it detection range of about 400 to 600 km against that same target. Of course AN/APG-81 is about a decade newer implementing much newer technology, including new T/R modules. So it likely has even bigger advantage than that due to each T/R module having higher output power and lower losses.


yeah, i do remember that APG-80 was claimed to have 2 times the range of APG-69v9 too
btw wasnt Apg-80 have the same size and power as APG-79
hornetfinn wrote:I believe Russian figures for Irbis-E and their other radars as they are achievable. Irbis-E is said to be able to detect 3 square meter target 350 to 400 km away within 100 square degree search area (which is very small search area). This means normal search mode detection range is likely about 230 to 270 km against that same 3 m^2 target depending on many variables. Those figures are because cued search usually has at least 50 percent longer range than normal search. Cued search is useful for targets which have been quite accurately detected by other sensors and is not that good for searching due to small search area.

Calculating all of the above together, we can estimate the following range performance against different RCS targets (numbers are rounded somewhat):

Irbis-E
0.0001 m^2: cued search 30 km, normal search: 20 km
0.001 m^2: cued 50 km, normal 35 km
0.01 m^2: cued 90 km, normal 60 km
0.1 m^2: cued 160 km, normal 115 km
1 m^2: cued 300 km, normal 200 km
10 m^2: cued 500 km, normal 350 km

AN/APG-79:
0.0001 m^2: cued search 32 km, normal search: 23 km
0.001 m^2: cued 55 km, normal 40 km
0.01 m^2: cued 100 km, normal 75 km
0.1 m^2: cued 180 km, normal 135 km
1 m^2: cued 330 km, normal 250 km
10 m^2: cued 600 km, normal 450 km

AN/APG-81 (conservative estimate):
0.0001 m^2: cued search 40 km, normal search: 30 km
0.001 m^2: cued 60 km, normal 40 km
0.01 m^2: cued 125 km, normal 85 km
0.1 m^2: cued 220 km, normal 150 km
1 m^2: cued 450 km, normal 300 km
10 m^2: cued 750 km, normal 500 km


these range seen too high to be honest , 60 km again targets with RCS = 0.001 m2 sound like performance of a ground radar
hornetfinn wrote:Comparing F-35 and any 4th gen fighter, including Su-35, in EW environment would not be pretty for any of those 4th gen fighters. Su-35 does have EW system in KNIRTI SAP 518. Problem is that it’s a sector jamming system. Those kinds of jammers can jam certain frequency or frequencies forward or aft section of the aircraft. The difference between F-35 EW system is that using APG-81, F-35 can concentrate the jamming power precisely towards enemy

APG-81 cant jam enemy from behind or at the side though
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Unread post30 Mar 2015, 14:43

btw what RAM are used to make the F-35? , it seem that most radar absorbing pain only work well around ( 9-10 Ghz)

image13.png

c3nr04087a-f3_hi-res.gif

13f07f.gif

03f6.gif

epl11646fig5.jpg

Shaping work well again most frequency, but dont reduce RCS as much
A year ago a study was published in the International Journal of Research in Aeronautical and Mechanical Engineering pegging the F-22 without RAM at -9 dBsm frontal, 30 dbSm lateral and 50 dbSm at X-Band. And around 20 dBsm in UHF/VFH.


Available at: http://www.ijrame.com/vol2issue1/V2i105.pdf

pitch_rcs_b2-sim.png
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Unread post30 Mar 2015, 14:50

Thanks for all your input 'eloise' (a lot goes over my head though) meanwhile here is some old info: (search on key distinct words on this forum to find the original discussion or similar info). Already we know the F-35s are manufactured to extreme tight tolerances for the outer mold line. Recently there was info about old/new paint systems in use - newer ones will save money - being applied by robots and other weird stuff. :mrgreen: More info on request - or search forum etc.

It is late at night in my part of the world with a large thunderstorm about to put the hammer down here so I'll just give some URLs for paint: http://www.af.mil/News/ArticleDisplay/t ... craft.aspx
OR
http://www.denix.osd.mil/awards/upload/ ... e-Base.pdf
&
http://www.dailytech.com/F35+Stealth+Co ... e21321.htm
"According to November 2005 reports, the US Air Force states that the F-22 has the lowest RCS of any manned aircraft in the USAF inventory, with a frontal RCS of 0.0001~0.0002 m2, marble sized in frontal aspect. According to these reports, the F-35 is said to have an RCS equal to a metal golf ball, about 0.0015m2, which is about 5 to 10 times greater than the minimal frontal RCS of F/A-22. The F-35 has a lower RCS than the F-117 and is comparable to the B-2, which was half that of the older F-117. Other reports claim that the F-35 is said to have an smaller RCS head on than the F-22, but from all other angles the F-35 RCS is greater. By comparison, the RCS of the Mig-29 is about 5m2."

Source: http://www.globalsecurity.org/military/ ... design.htm

F-35C STEALTH ON THE CARRIER DECK MEANS HIGH PERFORMANCE, LOW MAINTENANCE

"...The F-35 achieves its Very Low Observable stealth performance through its fundamental design, its external shape and its manufacturing processes, which control tolerances to less than half the diameter of a human hair. Special coatings are added to further reduce radar signature...."

Source: http://www.jsf.mil/news/documents/20080 ... ARRIER.rtf

Production techniques gear F-35 for stealth

"...In addition to machining advances that allow LM to achieve high manufacturing tolerances, advances have also been made in the composition of the radar-absorbent structure (RAS) of the aircraft. This Linhart said, is "completely different" from earlier RAS materials in the way it is resistant to chipping, even in the face of bird-strikes...."

Source: http://www.navy.mi.th/nrdo/jane/dev_w/p ... July48.pdf

Lockheed Gives a Peek at New JSF Stealth Material Concept
17 May 2010 Amy Butler

"It is called "fiber mat," and Tom Burbage, executive vice president of F-35 program integration for Lockheed Martin says it is "the single, biggest technological breakthrough we've had on this program." He says that a new process to blend stealth qualities into composite material avoided the need for stealthy appliqués and coatings. Using a new process, Lockheed officials are curing the stealthy, fiber mat substance into the composite skin of the aircraft, according to Burbage. It “makes this airplane extremely rugged. You literally have to damage the airplane to reduce the signature,” he said in an interview with Aviation Week in Fort Worth. This top-fiber mat surface takes the place of metallic paint that was used on earlier stealthy aircraft designs. The composite skin of the F-35 actually contains this layer of fiber mat, and it can help carry structural loads in the aircraft, Burbage adds. Lockheed Martin declined to provide further details on fiber mat because they are classified. But the disclosure of this new substance comes at a time when Lockheed Martin officials are arguing that maintenance costs for the F-35 will be lower than anticipated by operators...."

Source: http://www.aviationweek.com/Blogs.aspx? ... 80e3609ae1

New Stealth Concept Could Affect JSF Cost
17 May 2010 Amy Butler

"FORT WORTH — As the debate rages about Joint Strike Fighter life-cycle cost, Lockheed Martin officials are raising a previously unheard point to bolster their low-price claims — a new low-observability (LO) substance called fiber mat. Lockheed officials avoided the need to use stealthy appliqués and coatings by curing the substance into the composite skin of the aircraft, according to Tom Burbage, executive vice president of F-35 program integration for the company. It “makes this airplane extremely rugged. You literally have to damage the airplane to reduce the signature,” he said in an interview with AVIATION WEEK. This top-fiber mat surface takes the place of metallic paint that was used on earlier stealthy aircraft designs.

The composite skin of the F-35 actually contains this layer of fiber mat, and it can help carry structural loads in the aircraft, Burbage adds. The F-35 is about 42% composite by weight, Burbage says, compared to the F-22 at 22% and the F-16 at 2%. Lockheed Martin declined to provide further details on fiber mat because they are classified...."

Source: http://www.aviationweek.com/aw/generic/ ... el=defense

Composites Machining for the F-35
03 Aug 2010 Peter Zelinski, Senior Editor

“...Lockheed Martin’s precision machining of composite skin sections for the F-35 provides part of the reason why this plane saves money for U.S. taxpayers. That machining makes the plane compelling in ways that have led other countries to take up some of the cost. Here is a look at a high-value, highly engineered machining process for the Joint Strike Fighter aircraft....

...The F-35 features “supportable” VLO. That is, the VLO on this plane comes with very low maintenance cost. Stealth aircraft of the past couldn’t make that claim. Because radar detects sharp edges, even small mismatches between exterior parts on past VLO planes were smoothed out using epoxy. The epoxy would dry, harden and separate in the field—meaning it had to be frequently inspected and replaced.

By contrast, adjacent parts of the F-35 match so fluidly and precisely that no epoxy is needed. The trouble with previous stealth aircraft has disappeared....”

Source: http://www.compositesworld.com/articles ... r-the-f-35

THE F-35 LOW OBSERVABILITY’S LIFELONG SUSTAINABILITY: A REVOLUTIONARY ASSET FOR 21ST CENTURY COMBAT AVIATION
22 Mar 2010 SLDinfo

"...Performance-wise, it is a very aggressive capability. From a design standpoint, it is a radical change from legacy systems. In legacy stealth, the stealth in effect is a parasitic application of a multiple stack-up of material systems done in final finish after the actual airframe is built and completed. In the case of the F-35, we’ve incorporated much of the LO system directly into the air frame itself. The materials have been manufactured right into the structure, so they have the durability and lifetime qualities. It makes them much more impervious to damage. It is a much simpler system with fewer materials to contend with....

...From day one, the supportable LO has been a key entity on the program and has had a profound influence on the very design of the airplane. In fact, the element that is manufactured into the skin was an initiative brought about by our LO maintenance discipline...."

Source: http://www.sldinfo.com/?p=6065

The F-35: Creating a 21st Century Fighter
A White Paper By: Lockheed Martin

“...As Bill Grant, Lockheed Martin F-35 Supportable Low Observables Integrated Product Team leader, has put it:
From day one, supportable LO has been a key entity on the program and has had a profound influence on the very design of the airplane. In fact, the element that is manufactured into the skin was an initiative brought about by our LO maintenance discipline. We’ve also had a profound influence on the selection of the materials and then once they were decided upon, we helped refine the properties to make them more workable for field use.

And Grant added:
Our system requirement was for end of life, which means that throughout the 8,000-hour service life of the jet, it is to remain fully mission-capable. So we anticipated that the amount of maintenance that would be done over the life of the airplane and anticipated that in the design. So when we deliver the jet, it’s delivered with a significant margin of degradation that’s allowed for all of these types of repairs over the life of the airplane, again, without having to return to the depot for refurbishment. There may be some cosmetic-based reasons why the jet might go back to a facility to get its appearance improved, but from a performance-standpoint we recognize no need to do that....”

Source: http://www.sldinfo.com/whitepapers/the- ... y-fighter/

The F-35’s Race Against Time
Nov 2012 By John A. Tirpak Executive Editor

“...When it comes to maintainable stealth design, the F-35 represents the state of the art, O’Bryan said, superior even to the F-22 Raptor, USAF’s top-of-the-line air superiority aircraft. The F-22 requires heavy doses of regular and expensive low observable materials maintenance. F-35 stealth surfaces, by contrast, are extremely resilient in all conditions, ac-cording to the Lockheed team. "We’ve taken it to a different level," O’Bryan said. The stealth of the production F-35 —verified in radar cross section tests performed on classified western test ranges — is better than that of any aircraft other than the F-22. This, he went on, is true in part because the conductive materials needed to absorb and disperse in-coming radar energy are baked directly into the aircraft’s multilayer composite skin and structure.

Moreover, the surface material smoothes out over time, slightly reducing the F-35’s original radar signature, according to the Lockheed Martin official. Only serious structural damage will disturb the F-35’s low observability, O’Bryan said, and Lockheed Martin has devised an array of field repairs that can restore full stealthiness in just a few hours.

Dramatic Stealthiness
The F-35’s radar cross section, or RCS, has a "maintenance margin," O’Bryan explained, meaning it’s "always better than the spec." Minor scratches and even dents won’t affect the F-35’s stealth qualities enough to degrade its combat performance, in the estimation of the company. Field equipment will be able to assess RCS right on the flight line, using far less cumbersome gear than has previously been needed to make such calculations....”

Source: http://www.airforce-magazine.com/Magazi ... ghter.aspx
A4G Skyhawk: www.faaaa.asn.au/spazsinbad-a4g/ & www.youtube.com/channel/UCwqC_s6gcCVvG7NOge3qfAQ/videos?view_as=subscriber
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Unread post31 Mar 2015, 11:18

eloise wrote:yeah, i do remember that APG-80 was claimed to have 2 times the range of APG-69v9 too
btw wasnt Apg-80 have the same size and power as APG-79


APG-80 is smaller in size and power to APG-79. APG-80 is designed to fit inside the smaller 600mm diameter class nose of F-16 and APG-79 the larger 700mm class nose of Super Hornet. This means that APG-80 has about 75% of the range performance of APG-79 if both are using similar construction and same T/R modules (lower power, smaller antenna area).

eloise wrote:these range seen too high to be honest , 60 km again targets with RCS = 0.001 m2 sound like performance of a ground radar


That might be, I was just trying to show the difference between different radars. However, APG-79 does have huge amount of power, equaling many long range surveillance radars from 1980's and older.

Look here: https://ericpalmer.files.wordpress.com/2009/06/nmarler_apg79aesa.pdf

At the last page there is APG-79 power supply specs. I states that it has about 18 kVA power supply, which equals about 14.4 kW. With now pretty standard 85-90 percent efficiency, this means the radar can use about 12.5 kW of power. With AESA the main things that use power is the transmitters (T/R modules) and processing system. As modern processing systems use fairly low amount of power, most of that power goes to transmission. Let's say that APG-79 uses about 80 percent for transmission and rest goes to other radar requirements (mostly processing system). This means APG-79 would have 10 kW power available for transmitters. Of course not all of this would go into radiated power as much of it would be turned to heat due to T/R module inefficiencies. Modern T/R modules have PAE of about 40-60 percent using GaAs modules depending on their exact requirements (power, bandwidth, temperature etc). This means APG-79 has about 4-6 kW radiated average output power capability unless it uses exceptionally good or bad modules. As a sidenote, Irbis-E is said to have 5 kW maximum average output power and most fighter radars have average output power of about 1 kW. F-14 and MiG-31 radars have or had about 2 to 2.5 kW of average power. Interestingly, long range (240 nautical miles) surveillance radar AN/TPS-75 has a average power output of 4.7 kW: http://www.radartutorial.eu/19.kartei/karte103.en.html

Average power output is the only power that affects the radar range performance and peak power is just a side-effect of producing it. Average power also is the power that needs to be fulfilled by the power supply. I see it pretty certain that AN/APG-79 has about equal average output power level to Irbis-E used in Su-35. Higher efficiency of AESA should easily overcome the larger diameter antenna of PESA Irbis-E. AN/APG-81 likely has quite a bit more as it has more and likely newer (higher efficiency and higher power) modules and probably has better cooling capacity. I see it possibly having closer to 10 kW average output power, which is huge amount of power for a fighter radar.
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