Physics of tethered autogyros, autogyro rotors, and windmills at an angle of incidence to the wind

In French language: Rz (kg) = 1/2 x Cz du profil x densité de l’air x somme des surfaces des pales (m²) x vitesse d’extrémité des pales (m/s) au carré / (9.81 x 3).

Rough translation, by replacing kg with N:
Lift (N) = 1/2 x CL of the blade profile x rho (air density) x whole blade area (m²) x tip speed (m/s) squared / 3.

This not complete equation works from the blade area, not the disc area. The division by 3 is due to the efficiency of the rotor, the speed of the blades at the root being zero.

Unfortunately I have no reliable source for this equation, as I found it on forums. For example on https://www.forum-autogire.com/t2110-Tra-n-e-rotor-et-altitude.htm?q=profil :

Équation de portance
F portance =1/2 rô V carré S Cz
Équation de traînée
F traînée= 1/2 rô V carré S Cx.

Portance = lift; traînée = drag. On this equation division by 3 is not mentioned.

If the blade area is 1.08 m² (as you indicate) instead of 1.12 m² as I mentioned, the lift (in kg) would be 190 kg.

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