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More modern is the theory about the continuous curvature.

Madrat

You have to consider the following points.
Any stealth fighter uses basic radar reflection angles, it is around 30 degrees, this is based upon the mathematics of Ufimtsev , basicly all the aircraft surfaces and edges should be align upon that angle

Not really, Maxwell, Sommerfeld are more important.
Ufimtsev mathematics allowed only the estimation of the RCS.

This will be in opposition to the basic canard aerodynamics, if you check the picture of the JSF with canards you posted you will see it is basicly a triangle, its leading and trailing edge have the same angle and and its wing has the same angle.

Always short coupled and the only long coupled US Canard ends in a fiasco.;)

If you compare that to an eurofighter Typhoon you will see from the aerodynamic point of view it is much easier to give that angle to the trailing edge of the wing than to the canard. Its canards need to be high aspect ratio while the first stealthy JSF with canards picture shows a low aspect ratio canard.
Besides most canards are above the wing and most have dihedral.
this makes aerodynamicly speaking harder to keep the basic angles for planforming

What is whit the diadral of the F-22 wing?

The F-22 has a planforming which blends better that angle with the basic aerodynamics, but canards in the Typhoon and other modern fighters need trailings edges with a different angles with respect their leading edges.

The F-22 planform dump not all reflection to the same point. Simpel the leading edge of the wing is twisted and inlets pointed down. The leading edge of the fins and inlet points in different direction. Inlets down and leading edge up. 😉

If you look at the F-22, you can see the trailing edge of the tailplane do have the same angle of the wing

Really, and what with this differents angle?

Your problem, we are in the optical behavior (HF) and for this point is continuous curvature the better choice.

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First of all, canards are analogous to stabs, not TVC.

And one thing that is often overlooked with TVC is that the effectiveness (or strength) of any control moment they impart on an airframe is totally independant of airspeed and/or air density (i.e. altitude).

Canards, like all regular control surfaces, rely on airflow to be effective. TVC can effect the same pitching force on an airframe whether the airspeed is ZERO or many hundreds of knots. Not so with canards (or stabs, for that matter).

At many hundereds knots is a stab or Canard, Evelons more effective simple the can produce more force as a TVC can do . You bleed more energy in the curves with TVC. TVC is usefull for low speed aircircus manoeuvre but speed is live. Then has the F-22 only 2D TVC and not 3D the nose pointing abilities with 2D TVC are only marginal!

Not really we should not forget the orginator for the US TVC is Dr. Wolfgang Herbst (MBB).
With a g-onset rate of 15g/s what sense make then a TVC?

I’m sure that’s the reason.:rolleyes:

As for the X-32, it was ugly as sin, but it was the hover underperformance, that was the main issue.

And fly never supersonic after after vertical take off.
Had some pop stalls.

The point is that from an aerodynamics point of view, canard-deltas offer no advantages over wing-tails, and that they are at a dinsinct DISadvantage RCS-wise.

Exactly. Thing is, canards (like VG wings) are a BAD solution if you want to minimize RCS.

Not really with wing-tails need you a second fin or you have great RCS problem 90° between fin and tail. The Second fin caused now a RCS problem too. More weathered skin and a second leading and trailing edge and this trailing edge is longer as the leading edge at the Thypoon Canard.
Then is between your wing and tail a gap this is a reflector simpel it’s a change in the resistance. The only way round this problem is avoid a tail (B2).
Then change a great dihedral angle at a Canard the polarization or transforms circular polarizationin to linear polarization. A polarization mismatch damped ~30dB.