Long-ESA — how a working canard works

Whole-aircraft RANS, 372k cells, 55 m/s — the same instrument the CS-9 was condemned with, pointed at a long-coupled canard of the lineage that history says works. Traces are coloured by the induced vertical velocity, so undisturbed air reads neutral and only the wake shows. The two pins carry the stability story: the grey centre-of-gravity pin is fixed; the blue neutral-point pin sits half a metre behind it and moves aft as alpha rises — the margin grows exactly where the CS-9's vanished. The vane at the wing root is the measured angle of the air actually arriving there — the canard's shield.
The streak paths are the computed flow. The shimmer is stylistic — a steady solve carries no turbulence to animate — so its amplitude is tied to the local vertical velocity, meaning disturbed air visibly jitters more than clean air.

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CG neutral point

At this state (elevators at rest)

Lift coefficient CL
Drag coefficient CD
Root arriving-air angle

Static margin, solo pilot

What the wing root actually sees

The neutral point moves AFT with alpha — static margin +43.0% in the low band, +50.7% in the 4–8° band, deeply stable across the whole CG envelope. The same downwash sheet that robbed the CS-9's root here shields it: 5.5° shed off the root's incidence at α 8.
angle of attack