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- - Belgium selects F-35 over Typhoon (https://www.pprune.org/military-aviation/614631-belgium-selects-f-35-over-typhoon.html)

Quote:

Originally Posted by orca (Post 10293183)

......It also gives a higher quality track at range (and therefore higher range) due to the shape of the beam.

How do you mean, Orca?

Quote:

Originally Posted by orca (Post 10293183)

Hi Jacko,

Pirate is (I believe) fabulous...but the basis of my opinion is that the fundamental here is the ability to send enough information with a small enough latency for a weapon to acquire and guide.

A mech scan can do it for host platform weapons and has been shown to be able to do it in some circumstances for wingmen via link.

What AESA gives you is ultra low latency - because you dont wait for the next sweep to update a track. It also gives a higher quality track at range (and therefore higher range) due to the shape of the beam. The update rate allows each player to scan a huge volume of airspace - siro +/- 60 degrees in azimuth and elevation and all tracks are high quality. Mech scans can’t do this. This combined with a better MIDS fit allows you to off board more messages. In other words - it becomes ‘to everybody, every day’. MIDS JTRS keeps on giving because you can get your own radar to do its own mini scan around MIDS tracks - whilst doing its thing at not far off the speed of light!

In slack handfuls MIDS JTRS takes data rates up above 1Mbps in comparison with about 100kbps for other terminals.

I am a big supporter of the AESA radar upgrades planned for Typhoon but have lost track on how they are progressing.

Meteor’s latent kinematic capability will be unlocked by a AESA and conversely not maximised with mech scan. No point having a long stick and not being able to see far enough! (My opinion only.).

Thank you for that info orca. For years they [we] tried to achieve paired firings on the F4k it never was successful analogue systems, as you state just didn't have the capacity to communicate.

With the digital era, things have changed.

Hi Jacko,

If you think about an AESA as a Raster type scan but using a pencil beam - so a thinner elongated main lobe than a Mech Scan - with the ability to scan at a very high rate you get the benefit of more power in a dense lobe. (Although the AESA May actually use s pseudo random scan in practice).
AESA can also have a better signal to noise ratio than other systems.
Contributing to a longer range track is also the ability of the radar set to achieve multiple inputs by prioritising the scan around an initial hit. As discussed before there is no real loss in overall performance as the scan rate is so high. Rather than waiting for the next re-visit of the main lobe in two, four (or so) scans time - the set scans around the first detection and therefore track builds where a mech scan may simply not have the updates to meet its own ‘threshold’ for displaying a track.

What AESA gives you is ultra low latency - because you dont wait for the next sweep to update a track.

When I heard John Roulston brief Captor in 2002, he stressed that the radar was engineered with a lightweight antenna, robust gimbals and big motors so that it was not stuck in a constant raster pattern. It could intersperse the search raster with loopbacks to hit high-priority targets. Roulston (correctly) believed that AESA was not ready (even the APG-79 had a lot of bugs that needed to be worked out) and that commercial RF technology would make it less costly and more efficient in a later generation. Edinburgh was also talking about repositioners by the early 2000s, to support "shoot and crank" tactics with Meteor-type weapons.

Returning to the land of moules and lambic: while Eurofighter was not selected, they seem to have given the Borg a harder time than before, unless the Belgians are telling porkies about their terms. Not only do they seem to have secured a lower price than the partners, but by buying in 2021 they should get the new processor and displays, without being assessed for a share of R&D or having to pony up for upgrades on pre-2021 jets.

I’m sure that the logic holds - that a mech raster scan can be interrupted to conduct a ‘high density update’ on a contact - that’s essentially a high fidelity/ confirmatory Track While Scan. The AESA gives you Scan While Track. The difference being all targets can be similarly updated using rapid beam shift not just a high priority one/ next in your shot list etc.

Just fpr the sake of information, french "JTRS" ERS-a is presently in test in Istres as part of the contact program (based on ESSOR waveforms)

Quote:

Originally Posted by orca (Post 10295883)

Even the F3 in its latter years had "priority track"? Scanner would break from four bar scan to dwell over target(s) of interest without giving the game away,targets of interest going in and out of memory? Having just left the Typhoon world,not much has changed in the mechanical scanned world,remember MScan is 20+ years old now? Agreed faster scanner slew rates and lower noise floors compared to the F3 have made a difference in detection range,but the fundamentals haven't changed that much?