Five more high-resolution images. The second one has been shared before.
Very recent (November 25, 2019) publication of "Research on impact of canard to RCS" by 611. The article seems to have been submitted in 2017.
It is interesting to note 2.2 where Canard configuration is inherently better than conventional on the side.
- Comparison of conventional and canard configurations of otherwise the same fuselage, based on F-35.
- Before improvement on canard configuration, compared to conventional layout, Canard has
- Slightly worse RCS return in frontal area from 0 to 30 degrees because:
- Canard aft edge reflection is exposed while conventional horizontal stabilizer is blocked by main wing.
- Sharp end of aft edge of canard.
- The gap between canard and fuselage is another strong contributor, but mostly to high frequency (C band).
- Much less RCS return from the side, from 30 to 90 degrees, because conventional horizontal and vertical stabilizer forms a strong reflector while canard does not.
- Use radar absorbent structure (not paint) on all edges, the light grayish green area. It is much better than paint in terms of frequency band and size.
- Smooth curvature and seal of the inner edge of canard.
- Cut the corner of canard aft edge.
- After improvement, the conclusion is that canard configuration with proper measures is equal to conventional configuration in RCS.
- As to the "canard moving increase RCS":
- the test shows that within +- 5 degree movement (in cruising), there is both increase and also decrease (-5 degree). Overall neglect-able.
- When the canard must be turned more than 5 degrees, the aircraft is in a situation where the whole RCS has drastically increased (close dog fight or violent maneuver) making canard's contribution neglect-able or the whole stealth thing non-existent.
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Interesting that we are promoting a study of canards and conventional tail RCS based on the F-35 fuselage, showing that RCS is better from the side with the canard because of the strong reflector created by the horizontal and vertical fin junctures.....in order to affirm the use of canards on the J-20
Can’t say this by definite, but I think even if they were post a paper with j-20, the conclusion would be still the same.I had the same impression initially and maybe i thought it is some typo error between J-20 and F-35. If the aim is to affirm the use of canards on the J-20, it has the attributes of a strawman logic in approach. I would love to see the study published using the J-20 as the primary platform of interest and not on the F-35 which does not it. That would probably be a one way ticket to the "Gulag"..
Can you outline your reasoning to support your view that the conclusion will still be the same.Can’t say this by definite, but I think even if they were post a paper with j-20, the conclusion would be still the same.
This is a very common practice in academic when certain part of your content or data is keep in secret, then using a public database or a module would be the ‘go to’ method for publishing your achievement.
Can you outline your reasoning to support your view that the conclusion will still be the same.
As with everything especially in academic, the devil is in the details. If you are presenting a module as a surrogate, then you would first have to justify why your chosen module is even reasonably (logically) and necessarily (empirically) sound.
I still recall somewhere that there was a source stating that the J-20 canards were radar transparent to -30 dBsm, i.e, limiting the airframe to that dBsm rating. Unfortunately, I haven't been able to find it, and I was hoping this paper would give corroborating evidence of the stealth level.
In other news, I don't think the direct link was included, so...
The preamble on that report says it all "There are so many affect factors about the fighter stealth design". In other words, the individual parts and their sum are not necessarily the same.