Gnome-Rhône 18L

The Gnome et Rhône 18L was a French-designed twin-row 18-cylinder air-cooled radial engine. The 18L was a large step up in terms of displacement, power and number of cylinders. The majority of Gnome-Rhone engines were either 7, 9 or 14 cylinders. The engine was never put into series production due to the negligible market interest and the company's concentration on the production of 14-cylinder engines, which very quickly approached the performance of the larger model. However, the 18-cylinder model was further developed in the versions 18P with a two-speed compressor (1650 cv, 2400 rpm) and 18R with a central bearing (2150 cv, 2500 rpm), the latter variant achieved in tests in 1946 a power of 2400 cv at 2600 rpm. Eventually SNECMA (the successor of Gnome et Rhône) undertook licensed production of the Bristol Hercules engine instead.