Abstract: An annular, radial flow gas turbine engine and airborne vehicle utilizing same for jet propulsion. The engine comprises counter-rotating rotors and a compressor section with counter-rotating annular rows of intermeshing compressor blades, an annular combustion section common to both rotors wherein the combustion zone is defined by oppositely rotating rotor walls, and a turbine section made up of annular rows of counter-rotating exhaust turbine blades. No stator blades are present in either the compressor or the turbine sections.The craft comprises a central hub on which the engine rotors rotate on thrust bearings, and air bearings maintain rotor tolerances with respect to each other and to nonrotating shell portions above and below the engine rotors. Air inlet guide vanes leading to the compressor section are also housed in the hub portion of the craft.