background image
An Overview of Some S-Rotor Publications . . .
1.The Wing Rotor in Theory and Practice, by Sigurd J. Savonius, Eng. Capt. Lt.N.R., published
by Savonius & Co., Helsingfors, Finland, 1925, 39 pp.
Written by the inventor of the wind machine, this booklet describes principles of operation,
construction of various models built by the inventor, and some test results on those models. A
comparison is made with the performance of the rotor and some standard multi-blade windmills.
The conclusions which Savonius drew from his tests seem to contradict the experience of all
others: he claimed that his rotor was considerably more efficient than a multiblade windmill of
the comparable swept surface area.