This propeller went to France.
The diameter of the small 1700 mm. Power 160 hp Speed - 232 km/h.
Conventional airfoils are not reached. At low speeds - stall, the low thrust noise. Designed specifically airfoil based on NASA-44. Now everything should be fine - high thrust at the start, a high thrust at speed.
This is not quite true.
This profile - it is only the basis for the development of its own special profile. This new profile has the necessary properties to ensure the required speed range.
No known profiles do not possess the desired characteristics.