China Flanker Thread II

[b787]

. I probably only understand 10 % of what is written

you will not understand what i said because for that you need to understand the 1, 2, 3 of basic electromagnetism and basic concepts of antenna design

If you do not understand those basics, you can not understand what is an AESA, you need to understand what is an antenna polar diagram, to understand EASAs
and its directivity

AESA are not omnidirectional but use out of phase in phase features to achiever beam steering.

Old radars used a single TR module, modern radars can use 1600 modules thus you have 1600 mini-radars, thus miniaturization and computer play a part in what is an AESA, other factors like reflectors, 1/4 wavelength are still used, but basically still will be voltage and directivity what play the part in the range of radars.

Thus engines like 117S still are playing a big part in the range of Irbis, J-16 is unlikely to have the same type of radar with engines of 10% to 20% less thrust.

 

[latenlazy]

Honestly do you believe that?

A German fighter like the Me-262 with four dipole arrays and and Jumo 004 can not compare to an F-15 or a F-18 with AESAs with many embedded arrays in the hundreds and better computer power plus much more powerful engines.

But China has no engine on J-16 to power an Irbis, neither China has a time gap in technology of 2 or 3 decades with Russia in radar technology.

But any radar modern or old use the same principle of a dipole Alternating current to generate microwaves, the only difference is the computer power to calculate and thus give better discrimination on the image



This basically shows you than an AESA is no more different to a WWII radar in physics, is the computer power that allows better images, what makes an AESA like an EYE is the hundreds of TR modules that similarly to the cones and rod of an eye and a powerful computer (human brain) will give you a detailed image and better search and tracking capability.

J-16 with Al-31s or even WS-10s will need enough power to get 400 km of range something unlikely using those engines or then will need additional electricity generators to the ones used in regular flankers adding extra weight.

Unless you have perfect 100% conversion of energy from your generator to your modules, how much A/C current gets delivered to push out microwaves isn't simply a function of how much electric power the engines can generate. If you only expect to turn on your radar at certain moments you could design it to store up a lot of current in capacitors before discharging them all, delivering more power to get increased range, with drop off as those banks are expended. Alternatively more efficient and smaller element sizes for electronic components can translate to less loss, and more available power. There are just a lot of ways where those increased range figures are plausible.

It also just occurred to me that we don't even know for a fact that the excess power being generated by the 117S is even going to the radar.

 

[b787]

.

It also just occurred to me that we don't even know for a fact that the excess power being generated by the 117S is even going to the radar.

the 117s generate electriciy, they will generate electricity for the radar

even civil airliners do it, i do not doubt China can built an AESA of 400 km of Range, but is unlikely J-16 can power it with Al-31s or even WS-10s, you can not expect Gripen to be able to have a very long range radar, the engine is weak, the long range heavy fighters always carry long range radars, because they usually have 2 engines and these are usually of high yield.

The engine always reduces the number of potential APUs and of course batteries, so is not like that, a powerful engine on a fighter will be always used to power the radar, and 117s do power Irbis.

J-16 will have troubles to power such a radar, if they use another engine maybe, but their engines still can not yield as much as 117.

 

[latenlazy]

the 117s generate electriciy, they will generate electricity for the radar

even civil airliners do it, i do not doubt China can built an AESA of 400 km of Range, but is unlikely J-16 can power it with Al-31s or even WS-10s, you can not expect Gripen to be able to have a very long range radar, the engine is weak, the long range heavy fighters always carry long range radars, because they usually have 2 engines and these are usually of high yield.

The engine always reduces the number of potential APUs and of course batteries, so is not like that, a powerful engine on a fighter will be always used to power the radar, and 117s do power Irbis.

J-16 will have troubles to power such a radar, if they use another engine maybe, but their engines still can not yield as much as 117.

But do we know for a fact that all of the difference in power generated is going to radar performance (there are other electrical systems istrg plane after all), because if it isn't then your point about weaker engines MUST mean weaker radar is moot.

 

[Air Force Brat]

the 117s generate electriciy, they will generate electricity for the radar

even civil airliners do it, i do not doubt China can built an AESA of 400 km of Range, but is unlikely J-16 can power it with Al-31s or even WS-10s, you can not expect Gripen to be able to have a very long range radar, the engine is weak, the long range heavy fighters always carry long range radars, because they usually have 2 engines and these are usually of high yield.

The engine always reduces the number of potential APUs and of course batteries, so is not like that, a powerful engine on a fighter will be always used to power the radar, and 117s do power Irbis.

J-16 will have troubles to power such a radar, if they use another engine maybe, but their engines still can not yield as much as 117.

Actually B787 your signature aircraft does NOT us bleed air for AC Generators, but in fact uses IDG instead of bleed air, in order to simplify aircraft systems and and preserve thrust??
The integrated drive generators or IDG generate plenty of power to manage the avionics systems, as well as other electrical needs of the aircraft. The aircraft does have several subsystems such as the RAT in order to provide safety and redundancy?

 

[Brumby]

But do we know for a fact that all of the difference in power generated is going to radar performance (there are other electrical systems istrg plane after all), because if it isn't then your point about weaker engines MUST mean weaker radar is moot.

Bingo. I have yet to see power generation as a limiting factor. Based on my limited understanding, it is the aperture power limitation in each transistor - at least that is what the APA technical report is telling me.

 

[Deino]

Guys ... STOP !!

This is the PLAAF-Flanker tread and if You not stop immediately with this off-topic stuff I will clean that tread.

We have a radar related separate tread .. so continue there.

Deino

 

[Air Force Brat]

Bingo. I have yet to see power generation as a limiting factor. Based on my limited understanding, it is the aperture power limitation in each transistor - at least that is what the APA technical report is telling me.

Exactly, and there is NO reason to think the Chinese Flankers are in any way lacking,,, I am very disappointed that there have been no pictures of the J-15 production birds doing work-ups on the carrier. It does sound as if she has been at sea, but we don't even seem to have all the great pictures we were getting a year ago??? Those birds no doubt have a very fine FCS as well as Avionics Bay full of very good stuff??? Hopefully we might see some J-15 pics after the new year celebrations?

 

[A.Man]

What Are New in Shenfei? I am certain: they are not SU-35's.

 

[Deino]

No, these are simply J-11B (dark grey) and BH (light grey) at SAC with a few J-11BS/BSH in the background. Anyway a nice image.

By the way any news on the J-11D ???

Deino