September 1939

From The Space Library

Igor I. Sikorsky made initial flights with the first successful single-main-rotor helicopter, precursor of the R-4 two-place design procured in 1942 by the AAF.

World's largest balloon, the Star of Poland, was unable to make stratospheric flight because of the German invasion. The United States had provided helium gas in August for this Polish effort and several American experts, including A. W. Stevens, provided technical assistance.

City Under the Sea a science fiction story by American Interplanetary Society founder Nathaniel Schachner appears in Fantastic Adventures magazine.