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JF-17 Thunder Multirole Fighter [Thread 5]

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Can anyone please answer, if chinese engine is being matured and readied for block III then where does RD-93ma fit in the picture? Is it for block II?
 
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Can anyone please answer, if chinese engine is being matured and readied for block III then where does RD-93ma fit in the picture? Is it for block II?

customers will have options to use either.
 
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I could be wrong , but all things being equal, PAF will likely go for the 93MA instead of the WS. The 93MA will have a lot more in common with the 93.

Already Russia and PAC are working on allowing PAC to overhaul the 93s. There are a lot of subsystems in the JF17 where PAF have chosen non-chinese when China was offering similar systems
 
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There is no standarization as such that what RCS would the RADAR design look into.

Wrong, there is a standard for the puls doppler tech and that is the same all over the world for similar radars, only because some people want to make KJ 7 here to something special now, doesn change the facts, that EVEN the manufacturer shows. Zhuk Me, RDY, PS 05, EL 2032, Apg 68, Captor M... all have the same 5m² as standard target size!

I could be wrong , but all things being equal, PAF will likely go for the 93MA instead of the WS. The 93MA will have a lot more in common with the 93.

But that's the problem, all things are not equal! The Chinese still struggle to develop even a comparable engine, otherwise PAF had chosen it directly. The 93MA also is based on the newer 33MK engine, which has credible too, which is why it can't be integrated into the older Mig 29 airframes, so the question would be, can it "simply" be integrated into the JF 17 Block 2 airframe, or are more credible changes needed, which would make it more likely for the Block 3 (if the Chinese still have no alternative).
 
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Regarding 'radar cross section' (RCS)...

The RCS figure is a 'fiction'. No, it does not mean anyone can make it up. It mean this value, while is a valid mathematical result attached to a body, said value is NOT constant but varies according to distance in relation to the seeking radar.

Can the F-22 have an RCS of 50 m2 ? Absolutely -- when it is a few meters from the seeking radar.

So when a body, be it the simple sphere or as complex as an aircraft, is reputed to have X meters/squared RCS, that 'X' is supposed to be accompanied by a distance from a seeking radar operating under a specific frequency range, or band, like the X band, for example.

If a radar have a maximum reach (range) of 100 km, using round figures for ease of understanding, then effective range is about 80-90% of that max. If a complex body is reputed to be 5 m2, then it begs the question of WHEN will that figure appears, inside that 80-90% range, or beyond ? So it could very well be that a complex body will be 5 m2 at 90 km. Or 10 m2 at 60 km. Or 20 m2 at 40 km. And so on...

Can a B-52 have an RCS of 1 m2 ? Absolutely -- when it is a few hundreds or even 1000 km from the seeking radar. So when will the B-52 have an RCS of 5 m2 ? May be at 800 km out.

Generally speaking, the more complex the body, the higher its RCS will be at any fixed distance compared to less and less complex bodies WHEN ALL BODIES ARE AT THE SAME DISTANCE.

EM wise, the F-22 is less complex a body than the F-16, even though the F-16 is physically smaller, because in radar detection, what is 'complex' and its degrees depends on these rules:

Control of...
- Quantity of radiators
- Array of radiators
- Modes of radiation

The F-22 just happens to be effective at obeying those rules than the F-16. It does not mean the F-16 and the B-52 somehow 'violated' those rules. It means they are LESS EFFICIENT at obeying those rules than the F-22 does, so in radar detection theory, physical complexity does not always equals to reception (or perception) complexity. That is why if we put the F-16 and F-22 at the same distance, any distance, to the seeking radar, the F-22 will have a lower RCS value. That is why radar engineers do not casually use any RCS figure as standalone but tries to accompany that figure with at least an operating frequency, if not frequency and distance.
 
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Regarding 'radar cross section' (RCS)...

The RCS figure is a 'fiction'. No, it does not mean anyone can make it up. It mean this value, while is a valid mathematical result attached to a body, said value is NOT constant but varies according to distance in relation to the seeking radar.

Can the F-22 have an RCS of 50 m2 ? Absolutely -- when it is a few meters from the seeking radar.

So when a body, be it the simple sphere or as complex as an aircraft, is reputed to have X meters/squared RCS, that 'X' is supposed to be accompanied by a distance from a seeking radar operating under a specific frequency range, or band, like the X band, for example.

If a radar have a maximum reach (range) of 100 km, using round figures for ease of understanding, then effective range is about 80-90% of that max. If a complex body is reputed to be 5 m2, then it begs the question of WHEN will that figure appears, inside that 80-90% range, or beyond ? So it could very well be that a complex body will be 5 m2 at 90 km. Or 10 m2 at 60 km. Or 20 m2 at 40 km. And so on...

Can a B-52 have an RCS of 1 m2 ? Absolutely -- when it is a few hundreds or even 1000 km from the seeking radar. So when will the B-52 have an RCS of 5 m2 ? May be at 800 km out.

Generally speaking, the more complex the body, the higher its RCS will be at any fixed distance compared to less and less complex bodies WHEN ALL BODIES ARE AT THE SAME DISTANCE.

EM wise, the F-22 is less complex a body than the F-16, even though the F-16 is physically smaller, because in radar detection, what is 'complex' and its degrees depends on these rules:

Control of...
- Quantity of radiators
- Array of radiators
- Modes of radiation

The F-22 just happens to be effective at obeying those rules than the F-16. It does not mean the F-16 and the B-52 somehow 'violated' those rules. It means they are LESS EFFICIENT at obeying those rules than the F-22 does, so in radar detection theory, physical complexity does not always equals to reception (or perception) complexity. That is why if we put the F-16 and F-22 at the same distance, any distance, to the seeking radar, the F-22 will have a lower RCS value. That is why radar engineers do not casually use any RCS figure as standalone but tries to accompany that figure with at least an operating frequency, if not frequency and distance.


Sir the Most latest source for KLJ-7 confirms that it can detect a 3m2 target at 130km.

Can you calculate us at what range it would detect a 5m2 rcs target?

Just mention the next, FC1 and F-10 avionics gap, the overall architecture avionics FC1 is more advanced than the F-10 instead of backward, and this is the advantage of FC1, such as electronic jamming systems FC1 is the most advanced than the F-10 are FC1 advanced cockpit design is significantly stronger than the F-10, but in a somewhat less subsystem FC1.Such as radar air search radar FC1 is 130 kilometers (three square meters target), the F-10 air search radar was 145 km (3 m2 target).In 2016, FC1-BLOCK2, new FC1 will install the whole operating system to more than four degrees, aerial refueling equipment, high-speed data link (data link FC1 than it is now much better), and so on

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Sir the Most latest source for KLJ-7 confirms that it can detect a 3m2 target at 130km.
The source I have seen says 130km but does not give the reference RCS. In the video, the engineer does not mention radar radar.
 
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Sir the Most latest source for KLJ-7 confirms that it can detect a 3m2 target at 130km.

Can you calculate us at what range it would detect a 5m2 rcs target?



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We should have serious reservations about that figure. This figure has just appeared out of nowhere. We know about claims that upgraded KLJ-7 has a detection range of 130 KM for a 5 sq M target. There is little reason to dispute this, since there exists a reference to support it and we know that KLJ-7 has gone through an upgrade, before which its range for 5 sq. M target was 110 KM. Taking the newly discovered figures would mean that KLJ-7 has gone through a second upgrade. I am a bit skeptical about that. We should look for confirmation of this figure. I am not saying that the figure of 130 KM detection range for 3 sq M target is necessarily wrong, but that we can not accept these figures as correct just like that.

About RCS and detection range:

For the given frequency and target size, there shall always be some signal returned by the target. To separate that signal from 'noise' a reference is required that would qualify a signal as being significant enough to be taken as a detection. For any radar that threshold value / reference happens to be the one that would be received from a X sq. M target Y KM away. So for a given fixed RCS X, there would be a maximum distance Y at which a return signal would be just above that threshold to be considered a valid detection.

For any target in the air, the RCS value would be fixed at any given angle of incidence. For a target flying straight at the emitter that RCS value would not change with the distance. As the distance becomes less and less, the return signal would become stronger and stronger. So, as @sancho has said, a standard figure of 5 sq. M is customarily used for PD radars, and thus they can be compared relative to one another as to which radar would detect a target at what range. There is nothing particularly special about this figure of 5 sq. M, except that a typical combat aircraft would have an RCS around 5 sq. M. This time passed a while back. Most modern combat air craft have a much smaller clean RCS than 5 sq. M (not SU-30 MKI) . But for the sake of comparison the figure of 5 sq. M is still used.
 
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