On a different topic, since the other one's obviously become annoying, something to think about when it comes to the radar when comapred to the Rafale.

The Rafale's radar diameter is said to be less than 600mm while the F-35's is 800mm. And the number of TRMs for both is 1000-1100 and 1600. Some reports says 1200-1400, but that's unlikely to be true considering the F-22's 900mm radar has 2000. Makes sense to have 400 less than 600-800 less in comparison on the F-35.

Assuming the Rafale's radar is 575mm and has 1000 TRMs, then on an 800mm radar, using RBE-2 AESA's TRMs, we get nearly 2000 TRMs. And in case the Rafale's radar has an impressive 1100 TRMs, although unlikely, but in theory, we can say the radar will have 2100+ TRMs. And at the MKI's scale, we get 2700+ and 3000+ TRMs.

If we assume the Rafale's radar is 600mm, then with 1000 and 1100 TRMs, for 800mm we get 1777 and 1955, and for 960mm we get 2500 and 2800+.

This clearly implies the Rafale's radar uses far more advanced TRMs, which gives it a greater number on any given size compared to American TRMs used on the F-35 by anywhere between 10 and 20%. What it means is the French TRMs are much more tightly packed, which implies a smaller beamwidth, which is good, since on AESAs, beamwidth is determined by the spacing between the TRMs. This give the radar greater range and resolution in comparison to a radar of similar size using American TRMs.

There are a few other interesting things we can surmise based on open source info. We know that the RBE-2 AESA doubles the detection range over its PESA cousin, which gives 140Km for a 3m2 target. So the AESA's range is theoretically 280Km for a 3m2 target, or 212 Km for a 1m2 target. And through American releases, we know that the F-22's radar has a range of 250Km against a 1m2 target. So, even with a much smaller radar, the Rafale's radar is competitive with the F-22's radar even though it's less than twice the size, primarily due to the technological differences in the TRMs, and the obvious superior system design, like cooling and packaging.

The F-22's radar was supposed to get an upgrade with new GaAs TRMs that could push its range to 400Km against a 1m2 target, but it appears the Americans have decided to funnel money towards a more advanced GaN based TRMs for the F-22's MLU. However this implies the F-35 uses much more advanced TRMs than the F-22 uses, which is actually well known, hence it should easily be able to outrange the F-22 in radar performance even with a slightly smaller 800mm radar. The superior packaging, cooling and processing should also help.

However, even though the Rafale's radar has superior TRMs and system design, the fact is that the F-35's radar is simply bigger and has more TRMs, which gives it a much higher range. The F-35's radar could in fact be as capable as the Irbis-E when it comes to range performance. And using techniques like linear frequency modulation or phase coding, it should be able to even exceed the Irbis-E's already impressive range performance by a significant margin.

So, when it comes to range performance, the Rafale has fallen victim to its own small form factor. In fact, this is why even the Chinese jets with larger radars will beat Rafale's radar range even while using older tech, never mind GaN.

The point I'm trying to make is since we are making the Rafale's TRMs in India, it would be prudent to see if we can make our own upscaled radar for the MKI, in case we are still stuck with GaAs. The MKI is not constrained by a small form factor, so the system packaging doesn't have to be as severe as on the Rafale. In fact, we may be able to get higher performance out of it. The higher TRM count should be able to outmatch the Chinese AESA on their Flankers.

Any thoughts?

@vstol Jockey