Are canards bad for stealth? - An Endless Discussion

Scott Kenny said:
Yet the B-2 has a smaller RCS than an F-117 or F-22.

Radar absorption works by allowing the radar waves to bounce multiple times inside the radar-absorbing materials or structures. This is most effective when the bounce path is more than 10 times the wavelength being absorbed.

Stealth in general works by controlling which directions the radar reflects to, and concentrating all reflections into the smallest possible number of very narrow directional "spikes".

If a big canard has to deflect less than half a degree to maintain trim in flight, that will have a much smaller effect on the RCS spikes than a small canard that needs to deflect 5 degrees to get the same effect on trim.
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care to see any RCS depends upon the angle of view, people do not care to see details, from some angles B-2 has a bigger RCS, but from other angles lower RCS ,

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The reason is simple reflecting angle
1743291441048.png
 
F-14ATomcat said:
read well what I am going to say.

Aircraft are designed upon operational use

Got it?
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Ooh, I bow before your supreme knowledge, if not manners.

Before lecturing people, maybe check if they might just know more than you do.

The irony is you appear to be lecturing me on precisely the point I made, having failed to understand what I said, or the point itself.
 
DWG said:
Ooh, I bow before your supreme knowledge, if not manners.

Before lecturing people, maybe check if they might just know more than you do.

The irony is you appear to be lecturing me on precisely the point I made, having failed to understand what I said, or the point itself.
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nobody owns the truth, truth owns it self, nobody defeats the truth, truth always wins
 
I would think one of the bigger issues now is how stealthy can ca canard be made to lower frequencies where low frequencies can cause resonance. This is why Russian and Chinese created VHF band surveillance radars with vertical polarization to gain resonance off the vertical tails of US 5th gen fighters.
 
F-14ATomcat said:
nobody owns the truth, truth owns it self, nobody defeats the truth, truth always wins
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Sigh, you missed the point, again.

I said: "There's no such thing as an ideal canard. Canards serve multiple functions, with each design optimising for different things."

You answered with a whole spew of irrelevant verbiage about stealth etc, but concluded with:

"But you are claiming not ideal canard does exist, but that is not true, canard position gives different results, if you want agility, the best is Rafale/IAI Lavi, for lower drag is X-31 or Eurofighter Typhoon."

You seem not to understand that you've just made my point: there is no such thing as an ideal canard, simply different designs optimised for different criteria.

Personally I doubt any design in the history of aviation has ever achieved 'ideal', the best we can hope for is simply good enough.
 
DWG said:
Sigh, you missed the point, again.

I said: "There's no such thing as an ideal canard. Canards serve multiple functions, with each design optimising for different things."

You answered with a whole spew of irrelevant verbiage about stealth etc, but concluded with:

"But you are claiming not ideal canard does exist, but that is not true, canard position gives different results, if you want agility, the best is Rafale/IAI Lavi, for lower drag is X-31 or Eurofighter Typhoon."

You seem not to understand that you've just made my point: there is no such thing as an ideal canard, simply different designs optimised for different criteria.

Personally I doubt any design in the history of aviation has ever achieved 'ideal', the best we can hope for is simply good enough.
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I agree, no problem
I understand your point,

I was just saying Eurofighter has a canard for lower downwash over the wing, thus longer arm but lower canard wing vortex interaction.

IAI Lavi has a higher set canard over the wing and closer for better vortices canard wing interactions, ideally an agile fighter will try to be like Rafale not like XB-70 or Tu-144
 
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stealthflanker said:
Too bad that every engineers and aircraft designers on the planet actually do those boring stuff to come up with that study which you showing off here.


NUMBERS MASON !!! even there are numbers there in the study. That's how you gauge how important stuff are not words "all aspect stealth" things. As the enemy is unlikely to have any control on what aspect you are presenting to it.

Like say that J-20 model, doing say 10 degrees and the RCS from 0.1 increased to say 2% in X-band so it's 0.102. Hostile plane can say can detect 1 sqm target at 240 km and the plane is say an 4.5 gen with RCS of 2 sqm. the J-20 Radar can detect target at 200 Km with RCS of 3 sqm. Who has the first look first shoot ? You start by using 4th root radar equation, simple one

4.5 gen detection range vs Canard plane = ((0.102/1)^(1/4))*240 = 135.6 km
J-20 Detection range vs the 4.5 = ((2/3)^(1/4))*200 =180 km

J-20 have the first-look and first shoot too likely despite having RCS penalty of 2% from 10 degrees canard deflection




and all you are doing so far are long speech, no substantial information just "canard bad". But i make my point that it's just not the cataclysmic thing you are trying to portray here. There are more reasons why not to use canard e.g flight control software, weight and volume of actuators, they are surmountable as well as RCS. You have to do trade studies to see whether the advantage worth the problem of having to make it stealth. J-20 showed Chinese designers are confident.
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Canard impact is benign, not catastrophic.Stop eyeballing rcs
 

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