JF-17's Radar Cross Section

[[PTF]Ali]

Is JF-17 frame has accurate radar cross section simulation in DCS right now? Cause it was meant to have very small radar cross section than most plane in DCS. Its stealthy Intakes and very small profile at front aspect,

 

Do we have accurate radar cross section even in DCS?

Edited August 10, 2020 by AliPG

[J20Stronk]

JF-17 has an RCS of 3m^2 in the sim, same as a MiG-21.

 

For comparison, the F-16C is 4m^2, F-15C and F-18C are 5, F-14 is 6. The CEII has the lowest at 1.5.

 

AFAIK stores, aspect and the physical shape and design do not affect RCS in the simulator. These RCS values are entered manually in the .lua entry for each aircraft.

 

As to whether 3m^2 is accurate for the JF-17, I'm not sure.

But seeing as this is a slightly upscaled F-7PG the RCS would be higher, perhaps 4m^2 like the Viper. The DSI's probably only help retain the 3m^2.

[[PTF]Ali]

Thats interesting btw, How about Jf-17 without pylons, It will affect Missiles and Radar notching in DCS?

[L0op8ack]

RCS value in lua is defined as 'front aspect'.

How RCS affect radar detection, depend on how the radar(which is painting JF-17) is implemented,

using a static RCS value, or build a common azimuth/RCS map, addtional RCS from pylons etc.

 

 

30% ~ 50% of front aspect RCS is generated by inlet/engine,

JF-17 with DSI use the same front aspect RCS of Mig-21, seems a bit wired.

Edited August 11, 2020 by L0op8ack

[AeriaGloria]

RCS value in lua is defined as 'front aspect'.

How RCS affect radar detection, depend on how the radar(which is painting JF-17) is implemented,

using a static RCS value, or build a common azimuth/RCS map, addtional RCS from pylons etc.

 

 

30% ~ 50% of front aspect RCS is generated by inlet/engine,

JF-17 with DSI use the same front aspect RCS of Mig-21, seems a bit wired.

 

Interesting, so DCS can have pylons increase RCS? Of course the holy grail is to have stores affect RCS, but I’ve always heard that’s impossible

[L0op8ack]

Interesting, so DCS can have pylons increase RCS? Of course the holy grail is to have stores affect RCS, but I’ve always heard that’s impossible

DCS do not limit your implement too much, it's all about complexity and performance.

[BlackPixxel]

Thats interesting btw, How about Jf-17 without pylons, It will affect Missiles and Radar notching in DCS?

 

Notching should not depend on RCS

[BlackPixxel]

Thats interesting btw, How about Jf-17 without pylons, It will affect Missiles and Radar notching in DCS?

 

Notching should not really depend on RCS

[uboats]

ED states that mig-21 RCS 3 m^2 is solid based on various sources.

the RCS in DCS is for front cross section (regardless of material) and with consideration of a typical weapon

if RCS=3 for MiG-21, then JF-17 with DSI should have smaller RCS,

but ED insists JF-17 should have same RCS as MIG-21 :huh:

Edited August 12, 2020 by uboats

[AeriaGloria]

I can get behind it being close enough, it’s slightly larger then 21 anyways, 21 doesn’t have visible fan either even though the intake, and 21bis also has that mesh that I assume is for boundary layer air.

 

Unless those RCS computer sims are used the way CFD is done for flight model, it will always be one of the more guess oriented parts of the sim

[dundun92]

I thought i recall reading one source that listed the MiG-21 having a head on RCS of 10 m^2, which would reasonably allow the JF-17 to be at 3m^2 (which sounds reasonable) and still be less than the MiG-21

[Galf]

ED states that mig-21 RCS 3 m^2 is solid based on various sources.

the RCS in DCS is for front cross section (regardless of material) and with consideration of a typical weapon

if RCS=3 for MiG-21, then JF-17 with DSI should have smaller RCS,

but ED insists JF-17 should have same RCS as MIG-21 :huh:

 

Pssst... a lot of the frontal cross section is the spinny engine blades. It's not just looking at the plane and calling it a day.

[uboats]

Pssst... a lot of the frontal cross section is the spinny engine blades. It's not just looking at the plane and calling it a day.

 

then could you tell us how DSI bump help improve the stealth from the the fan blade? ;)

[Galf]

then could you tell us how DSI bump help improve the stealth from the the fan blade? ;)

 

No, but at the same time I'll never say "plane X has a lower RCS because of plane Y"

RCS is not a straight cut and done deal

[uboats]

No, but at the same time I'll never say "plane X has a lower RCS because of plane Y"

RCS is not a straight cut and done deal

 

then why big airplane normally has relatively larger RCS?

yup, RCS is determined by many aspects. airplane size is one of them.

thunder has similar size of mig-21, so using mig-21 as ref is reasonable.

ED basically consider size (front cross section) plus a typical weapon for RCS in DCS. to make difference between airplane in similar size, other aspect like inlet etc should be considered.

Edited August 13, 2020 by uboats

[[PTF]Ali]

I don't want to mention real life events but when mirage 2000 were in collision course with JF-17 recent event, There are reports that they were not able to see jf-17s, May be it was because of SPJ or EW, but in most cases and confirmed JF-17 with 2 sidewinders and 2 SD-10 is really really stealthy at long ranges for old generation radars.

[[PTF]Ali]

then why big airplane normally has relatively larger RCS?

yup, RCS is determined by many aspects. airplane size is one of them.

thunder has similar size of mig-21, so using mig-21 as ref is reasonable.

ED basically consider size (front cross section) plus a typical weapon for RCS in DCS. to make difference between airplane in similar size, other aspect like inlet etc should be considered.

 

Jf-17 is even 1 foot smaller than f16 too :thumbup:, Mig21 has huge spine and has no composite material may be but jf-17 has.

[GumidekCZ]

On 8/14/2020 at 1:37 PM, [PTF]Ali said:

 

Jf-17 is even 1 foot smaller than f16 too :thumbup:, Mig21 has huge spine and has no composite material may be but jf-17 has.

Weak arguments, 1foot? spine? composite?

Try to create overlaped picture of all three of them with highlighted leading and trailing edges (pylons including), surface of the wall behind the radar and cockpit visivible through plexy glass - if gold used it helps to reduce RCS (F-16C). Or you can calculate monostatic RCS for all three airframes by any FEM analysis program capable of that. Like here: https://www.youtube.com/watch?v=74yQgEnCW3I
If you have the info about where and how many parts are made from composite at Jeff, show us... I never found any info about that.

This vid is also handy to understand RCS: https://www.youtube.com/watch?v=YvLPdtExJ0k

 

Edited November 25, 2021 by GumidekCZ

[GGTharos]

On 8/14/2020 at 7:29 AM, [PTF]Ali said:

I don't want to mention real life events but when mirage 2000 were in collision course with JF-17 recent event, There are reports that they were not able to see jf-17s, May be it was because of SPJ or EW, but in most cases and confirmed JF-17 with 2 sidewinders and 2 SD-10 is really really stealthy at long ranges for old generation radars.

So what?  How far were they?  It's not like the Mirage 2000 radar is some big powerful setup either.

On 8/12/2020 at 9:57 PM, uboats said:

yup, RCS is determined by many aspects. airplane size is one of them.

thunder has similar size of mig-21, so using mig-21 as ref is reasonable.

The MiG-21 was measured to have a 10m^2 RCS.   But, that's neither here nor there.  The RCS in DCS are mostly fiction and they can't be changed too much from the standard 5m^2 because, if I recall correctly, this significantly affects chaff function.  This isn't incorrect, the scale on which it happens is though.