With the failure of the Su-57. I see few other options for the Russian Air Force and Navy but the J-31. That said, any Russian Version of the J-31. Could easily include a fair number of Russian Components like the RD-93’s (turbofans) along with Avionics and Weapons. This should make it far more palatable to Russian Pride.

Honestly, while some think the idea in crazy! Yet, when asked for a plausible alternative. The response is usually silence…..:eek:

The only plausible alternative is Su-57. and the plane regardless how many being bought and what not, the plane is still in active development. and you also neglect traditional dynamics of Russian aircraft industries. Where there is a clear distinction on who build what. We know Su-57 is heavy fighter… so the job will go to Sukhoi, which later bought engine from either Salyut or Saturn and rated for the job. To take Su-57 job is basically a new aircraft, something bigger than J-31 and can take the Saturn or Salyut engine.

RD-93 in other hand is Klimov’s product, being Klimov it would means the job will be for MiG and We all here know MiG no longer in business in making heavy fighters. And Russia doesn’t seem to think of stealthy light/medium fighter.

This brought us to J-20 but then, can it take what Su-57 meant for ? Say built from the ground to accommodate multiple AESA arrays. This look simple but, it’s actually serious matter as it involve complex work on rebuilding the cooling and power generation and to provide space. And then J-20 use variant of AL-31FN which, differs from AL-31F and AL-41F1 in terms of gearbox placement and general size. This isnt trivial too as that would means if Russian wants to actually upgrade the thing, adding their 2nd stage engine. They would have to develop a new version with same gearbox placement as FN. and let’s not forget weapons compatibility like R-37M or cruise missile, this might entail development of new array of weapons too.

I don’t see those will help Russians… not at all.

I’m curious if we have kinda official size estimate for the J-31.

From what i see tho, this aircraft might be at weight class of MiG-35 given its RD-93 engine, therefore i speculate that the cooling capacity and the AESA radar that can be supported would be similar to those in MiG-29/35 article. The benefit is of course it can accommodate larger aperture compared to zhuk family. However edge treatment might reduce the available aperture.

Working from there i tried to estimate possible performance of the AESA radar that can be carried. The result was like 1452 elements assuming 90% antenna face are filled. 6 Watts per module with assumed cooling capacity of 6.5 kW/sqm of antenna aperture. The set is able to detect 3 sqm at 156 km and tracking 16 targets simultaneously. Trading the capacity to track targets can increase the range figure, although not by much. I would say quite promising figure for export fighter, especially if the RCS is low.

Then it’s up to how to manage it.

I would imagine some operational limit for the IRST. maybe for dogfight only or when it’s somewhat expected not searched by enemy radar .

Yes 4 to make it 6 like MiG-31M many alterations have to be done including removing the gun. and please dont rush. This is a forum board not a real time msn chat.

RIP to the Fallen.

uh quick question, Does Pakistan have interest toward J-31/FC-31 ?

That’s one engine demonstrator of NPO Salyut. Many labels it as the stage 2 engine tho, but can’t really sure if it is the one that would make it to the real production.

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Regarding Su-57 IRST tho.. the thing now is the magnitude. does it really turns as “beacon” when it used or it does increase RCS but does not increase radar detection range down to infinity.

Regarding LPI. Well interception is definitely possible, demonstration is rather sparse where publicly available information is that it require near 100 dB sensitivity which may not be practical. The big BUT however is that it is for ground attack radar, where several watts are what it needs to extract useful information from ground target. Air to air detection requires more power, otherwise one must accept short range detection which does not live up whoever expectation of having 100km++ range AAM’s and trying to be the hidden archer.

It is this more power that would make detection somewhat easier, at least in mainlobe where the plane is being painted and locked for missile shot.

Regarding Su-57 RHAWS tho and so is other’s RHAWS. unfortunately no one really know or can tell figures like how many antenna they have or how sensitive the receiver. Though some generalized figure can be made regarding sensitivity. Digital channelized receiver can be expected to have at least -80 to -85 dB while conventional Pre-amplified receiver is -65 dB while IFM is about -75 dB. Using Radar as RHAWS is feasible although it will be constrained by scan to scan problem (your radar look in a different direction when enemy looks elsewhere).

The other problem is whether one can process and categorize the signal But for aircraft target which may move in speed of more than Mach 1. there seems to be limit in what pulse compression or signal coding available. Which will help making practical RHAWS possible.

The best can be said in the end however is the Su-57 and so other planes can detect LPI Radar emmission at mainlobe.

i miss you TR1 X3