The Jendrassik Cs-1 was the world's first working turboprop engine. It was designed by Hungarian engineer György Jendrassik in 1937, and was intended to power a Hungarian twin-engine heavy fighter, the RMI-1.
The engine was designed by György Jendrassik in 1937 and built at Ganz Works. It ran for the first time in 1940, but problems with combustion stability limited the power to 400 hp, from the design goal of 1,000 hp. There was nothing inherently wrong with the design, however, and continued work on the flame cans should have allowed it to develop to full power.
All work on the engine was later stopped when the Hungarian Air Force selected the Messerschmitt Me 210 for the heavy fighter role, and the engine factory converted over to the Daimler-Benz DB 605 to power it. The prototype RMI-1 was later fitted with these engines in 1944.