PAK FA vs F-22A

[hornetfinn]

Element spacing limits how tightly you can pack them, but not the other way around. The limitations for the Russians is packaging the modules small enough to fit as many as US manufacturers can.

Actually there is also limits to how far apart you can pack them

Yes that is true. However both radars are pretty far away from having negative effects from too tight or too wide spacing of elements. If we assume antennas for both radars are of similar size (roughly 900 mm diameter) and wavelength of about 8-12 GHz, then they both are in the area where mutual coupling (too tight spacing) or grating lobes (too wide spacing) is not a problem. Another thing is that even if present, neither problem is not a show stopper. They just restrict or lower system performance from maximum possible.

My prediction is that AN/APG-77 is much better radar with higher performance all around. I would not be surprised if it has twice the range against similar targets. AN/APG-81 also likely has clear advantage over PAK FA radar when range alone is compared. Even Rafale and Gripen AESAs might well have roughly similar range performance compared to N036 despite being much smaller systems.

[mixelflick]

I wonder how much longer it'll be before the PAK FA and Raptor meet up?

We've seen it in the air with SU-35's, which I found fascinating. But to answer your question OP, the Raptor has it all over PAK FA and the various upgrades planned will likely keep it ahead. PAK FA is a beautiful bird. But beauty does not = combat effectiveness, and the U.S. has decades experience now in combat.

To expect the Russians (who lost a decade or more when the Soviet Union collapsed) to churn out an = or superior fighter just isn't realistic. The fact that the YF-22 and 23a prototypes were far ahead of it (in supercruise, stealth and avionics) over 25 years ago speaks volumes. Will it be effective vs. non-stealth aircraft? Likely, yes. But it is not the = of the F-35 nor F-22, and still has a long way to go before being combat ready. The Russians will soldier on with great 4th+ gen designs, their SU-35 for example being the gold standard for WVR combat. Going to be awhile on the PAK FA though, and their tiny order for such (just 12) reflects that...

[botsing]

The Russians will soldier on with great 4th+ gen designs, their SU-35 for example being the gold standard for WVR combat.

In what way is the Su-35 the gold standard for WVR?

[hythelday]

The Russians will soldier on with great 4th+ gen designs, their SU-35 for example being the gold standard for WVR combat.

In what way is the Su-35 the gold standard for WVR?

60deg off bore missiles of course.

[sprstdlyscottsmn]

The US has 90+ off boresight missiles, so not that.

[botsing]

As far as i know PAK-FA's nose is smaller than Flanker series

What, looking at that image, also stood out to me was that the verticals of the PAK-FA seems to be proportionally much smaller compared to the F-22 (and Flanker):

[sprstdlyscottsmn]

They are smaller, but they are all moving like on the Blackbird.

[arian]

Element spacing limits how tightly you can pack them, but not the other way around. The limitations for the Russians is packaging the modules small enough to fit as many as US manufacturers can.

Actually there is also limits to how far apart you can pack them

Yes that is true. However both radars are pretty far away from having negative effects from too tight or too wide spacing of elements. If we assume antennas for both radars are of similar size (roughly 900 mm diameter) and wavelength of about 8-12 GHz, then they both are in the area where mutual coupling (too tight spacing) or grating lobes (too wide spacing) is not a problem. Another thing is that even if present, neither problem is not a show stopper. They just restrict or lower system performance from maximum possible.

Agreed. Nobody is there yet where spacing is a problem yet. The issue with Russian AESA is manufacturing elements that are compact enough (for a given set of capabilities), and here the Russians are lagging behind. This isn't an assumption as it is based on their own claims of their manufacturing capabilities.

As far as i know PAK-FA's nose is smaller than Flanker series

It's smaller but the PAK-FA has a fixed antenna and the Flanker has a movable one, so the antenna doesn't sit in the same place in both places. So the Flanker's may well have a smaller dimension overall.

[geforcerfx]

I don't see any way in the Pak-Fa having a superior (frontal) radar to the F-22 until into the mid-late 2020's, and that's assuming the USAF doesn't upgrade the F-22's radars and computer system's to more modern equipment by then. I would assume the N036 is the first 10 watt module airborne radar for the Russians, all the Zhuk AESA's seem to only have 5 watt modules going off the distances they advertise (granted they increased density rather quick on those). The Pak Fa have the side array's and tail array does give it a nice kick up in situational awareness over the Su-35. But I find the F-35's DAS system to be a more feature rich system with comparable a2a tracking capabilities, but you get all the other features, missiles warning, 360 infared camera's and so on. I would rather see the F-22 get two IRST's in it's wing roots and have it's system upgraded to the AN/AAQ-37 with a modern HDM system added before they touch the radar.

[arian]

I don't see any way in the Pak-Fa having a superior (frontal) radar to the F-22 until into the mid-late 2020's, and that's assuming the USAF doesn't upgrade the F-22's radars and computer system's to more modern equipment by then. I would assume the N036 is the first 10 watt module airborne radar for the Russians, all the Zhuk AESA's seem to only have 5 watt modules going off the distances they advertise (granted they increased density rather quick on those)

Who says 10 watts? Nobody knows.

In any case the power alone isn't the only issue. Lots of other issues to consider. Think that only now they are developing the technology to make layered manufacturing of their modules. Which is at least 20 years behind the US.

[hornetfinn]

It's definitely impossible to say how powerful modules are used and what their other specs are. It's relatively simple to make powerful modules that are not very good otherwise. Powerful modules could have much more limited bandwidth, higher losses and higher noise figure along with lower efficiency (higher electrical power and cooling requirements). All these would make the radar less capable despite the nominal power. All the specs about Russian AESAs indicate they have relatively low power modules alond with more limited bandwidth and higher noise figures compared to Western modules. Their modules seem to be roughly similar to modules manufactured in USA about 25 years ago. This was the situation exactly 20 years ago in USA:

https://www.justice.gov/atr/case-document/complaint-188

13. Raytheon has produced more high power amplifier MMICs and T/R modules than any other firm. It was chosen in 1992 to supply the power amplifier for the ground-based radar ("GBR") for the Theater High Altitude Area Defense System. Under this program, Raytheon produced and delivered about 42,000 T/R modules containing 6-watt, X-band power amplifiers. In 1996, Raytheon won the development contract for the improved GBR. Raytheon is developing a 10-watt, wide band, high PAE X-band high power amplifier for this program, with a delivery goal of late 1997.

14. TI is the recognized leader in developing high power amplifier MMICs. As a second source to Raytheon on GBR, TI supplied about 28,000 T/R modules containing 6-watt X-band power amplifiers. TI also has been chosen to supply the advanced power amplifiers for the radar on the F-22 fighter; it already has produced 23,000 amplifiers and thousands more will be delivered. TI is very close to production of an X-band 10-watt wide band, high PAE amplifier. It also has developed an X-band 16-watt high power amplifier which is close to meeting DoD specifications.

Of course there is much more to AESAs beside T/R modules, including hardware and software. I'd say Russia has a lot of catching up to do to match F-22 capabilities in 2005, let alone when PAK FA actually enters service as F-22 is not standing still in technology or capabilities.

[mixelflick]

The Russians will soldier on with great 4th+ gen designs, their SU-35 for example being the gold standard for WVR combat.

In what way is the Su-35 the gold standard for WVR?

There is simply no other aircraft that can throw itself around the sky/execute such drastic nose pointing maneuvers as the SU-35. Sure, you can argue about HOBS missiles, possibly better acceleration etc from US 5th gen jets, but I've seen nothing come close to the most recent SU-35 display at MAKS, I think it was. It didn't even lose altitude after performing these loops, cobra's etc. If the F-35 or F-22 can do the same, I'd love to see it.

Either the US jets can't match those maneuvers or they're holding back. I'll concede it certainly could be the latter...

[botsing]

The Russians will soldier on with great 4th+ gen designs, their SU-35 for example being the gold standard for WVR combat.

In what way is the Su-35 the gold standard for WVR?

There is simply no other aircraft that can throw itself around the sky/execute such drastic nose pointing maneuvers as the SU-35

Ah right, throwing your aircraft around drastically is what makes you win the WVR engagement. So simple and elegant.

It makes me wonder though, why the country with the biggest military research budget ever, who knew quite well about this supermaneuverability, gave priority to several other properties, almost as if they know that in the total package it is not an advantage at all, crazy right?

[basher54321]

Either the US jets can't match those maneuvers or they're holding back. I'll concede it certainly could be the latter...

And nobody who flies an F-35 would give a toss because they know that they currently fly the gold standard (with F-22) in actual WVR & BVR combat - I don't know how many vets need to come on here and try to give some idea that actual combat has F all to do with an airshow performance!

[zero-one]

There is simply no other aircraft that can throw itself around the sky/execute such drastic nose pointing maneuvers as the SU-35. Sure, you can argue about HOBS missiles, possibly better acceleration etc from US 5th gen jets, but I've seen nothing come close to the most recent SU-35 display at MAKS, I think it was. It didn't even lose altitude after performing these loops, cobra's etc. If the F-35 or F-22 can do the same, I'd love to see it.

Either the US jets can't match those maneuvers or they're holding back. I'll concede it certainly could be the latter...

This actually has more to do with aerial demonstration doctrines than actual capability.

As test pilot Jon Beesly once said, the Russian live to perform what they call "ballistic" maneuvers where the plane is affected by external factors like Gravity, wind resistance etc. with most Russian demos you'll often see Flankers get extremely slow while they execute dazzling high alpha and post stall maneuvers. Its elegant and astounding to see but has nearly zero combat relevance.

American demos on the otherhand display lots of power and precission. I have yet to see a Flanker or any aircraft replicate the max performance take off routine of the Raptor. I have yet to see any of them complete a 360 minimum radius turn in just a little over 20 seconds shortly after said takeoff, while still havy with fuel.

The powerloop is unique in that at one point it anchors the nose in one spot and the plane is actually flying tail first.

Can the Raptor tumble around in the sky? Yes it can, they demonstrated that in departure control test and the pilot was able to recover, so if they wanted they could do that in a demo because they know its safe. But why? The Raptor's whole image is that its the most powerful aircraft out there, so the demo is centered around demonstrations of power.

You see American aircraft being used by other forces with different demo doctrines and you see different things as well. I saw a Dutch F-16 doing all kinds of crazy maneuvers I didn't know the F-16 could do. The Swiss F/A-18C has a very impressive demo too. It almost looked like it had TVC at times better than any US legacy hornet demo.

Its all about demo doctrines, Americans like to drive fast and do tight high G turns, being under control at all times. Its probably the most tactically relevant in the real world but not always the best thing to look a.