The Walter Atlas was a nine-cylinder, air-cooled, radial engine for aircraft use built in Czechoslovakia in the early 1930s.
The Atlas was the largest capacity and most powerful radial engine design developed by the Walter company. The engine was an attempt at high power output by using a much larger bore size than company's previous range. The engine was test run in spring 1930, encountering problems with cooling and operation.[1]
The engine appeared at the Paris Aerosalon in December of that year. The engine did not attract any customers, further development was cancelled in 1931 and the company moved to producing licensed versions of the Bristol Mercury, Pegasus and Gnome-Rhône 14M.[1]