01910oam 2200481I 450 991071285070332120200130090657.0(CKB)5470000002497676(OCoLC)1105632597(EXLCZ)99547000000249767620190625d1920 ua 0engurbn|||||||||txtrdacontentcrdamediacrrdacarrierDrag or negative traction of geared-down supporting propellers in the downward vertical glide of a helicopter /by A. Toussaint[Washington, D.C.] :National Advisory Committee for Aeronautics,1920.1 online resource (5 pages)Technical notes / National Advisory Committee for Aeronautics ;No. 21"September, 1920.""Resume translated from the French by the Paris Office, N.A.C.A.""Paper read by M. Toussaint, Engineer of the Aerotechnical Institute of the University of Paris, (St.-Cyr l'Ecole), before the Scientific Commission of the Aero Club of France, January 24th, 1920"--Page 1.No Federal Depository Library Program (FDLP) item number.Drag (Aerodynamics)Rotors (Helicopters)Drag (Aerodynamics)fastRotors (Helicopters)fastDrag (Aerodynamics)Rotors (Helicopters)Drag (Aerodynamics)Rotors (Helicopters)Toussaint A.214588United States.National Advisory Committee for Aeronautics,TRAALTRAALTRAALOCLCOGPOBOOK9910712850703321Drag or negative traction of geared-down supporting propellers in the downward vertical glide of a helicopter3447298UNINA