Jet Aircraft Travelling At Transonic Speed

History
A number of jet powerplants were suggested from the first instances of powered flight. René Lorin, Morize, Harris proposed systems for creating a jet efflux. In 1910 Henri Coandă filed a patent on a jet propulsion system which used piston-engine exhaust gases to add heat to an otherwise pure air stream compressed by rotating fan blades in a duct.
The "turbojet", was invented in the 1930s, independently by Frank Whittle and Hans von Ohain. The first turbojet aircraft to fly was the Heinkel He 178 prototype of the German Air Force, the Luftwaffe, piloted by Erich Warsitz on August 27, 1939.
The first flight of a jet engined aircraft to come to popular attention was the Italian Caproni Campini N.1 motorjet prototype that flew on August 27, 1940. Test pilot Major Mario De Bernardi of the Regia Aeronautica was at the controls. It was the first jet aircraft recognised by the Fédération Aéronautique Internationale (at the time the German He 178 program was still kept secret). Campini had proposed the motorjet in 1932.