Hi Doug,
I have a question about the tested multi-rotor.
The introduction presents a shaft of 70 feet, and seven rotors of 7 feet in diameter. 70 feet = 21 m, and 7 feet = 2.1 m. So the space between the rotors is 21/6 = 3.5 m.
mechanism which allows the shaft to tilt as much as 25 degrees from horizontal
So we will therefore assume that the elevation angle of the shaft is 25 degrees.
Sine of 25 degrees (shaft) is 0.4226. Sine of 65 degrees (rotor plane) is 0.9063.
So the vertical dimension of the shaft between two rotors is 3.5 X 0.4226 = 1.4791 m.
So the vertical dimension of a rotor is 2.1 x 0.9063 = 1.90323 m.
As a result apparently (excepted the first rotor) rotors do not harness fully fresh wind. With a shaft of 21 m and 25 degrees, one can fully accumulate a little less than 5 inclined rotors for a frontal airspace of a little more than 4 surfaces swept on a vertical plane. How do you explain a so high value in these conditions?