Figs.1,6,7,8 N.A.C.A. Technical Memorandum No. 358 Figure 1— Model of three-blade propeller driven by a 3 hp. electric motor for tests in wind tunnel. Figure 6.- A Focke free flying model helicopter driven by a 0.7 hp. gasoline engine. The model attained an altitude of 18 m.
NASA Technical Reports Server (NTRS)
Internet Archive · NASA Technical Reports · Public domain (US government work). Free to use for anything.
