A STUDY OF VORTEX RINGS IN AIR Open PDF Document Details Document Type Technical Report Publication Date Oct 26, 1955 Accession Number AD0081349 Entities People Rubén D. Spies Organizations Aerojet Rocketdyne Holdings Tags Communities of Interest Sensors DTIC Thesaurus Topics Contracts Generators Government Procurement Governments Gunpowder Intellectual Property Launching Law Motion Pictures Photographs Photography Procurement Propellants Reflection Shape Specifications