SNECMA 14R

The SNECMA 14R was a 14-cylinder two-row air-cooled radial engine developed in France just prior to the start of World War II from the Gnome-Rhône 14N. The 14N radial engine was itself an improved version of the popular pre-war Gnome-Rhône 14K Mistral Major series; designed and manufactured by Gnome et Rhône, a major French aircraft engine manufacturer whose origins pre-date the First World War.

The improved 14R was initially known as the Gnome-Rhône 14P and then the Gnome-Rhône 14R. There were several improvements such as the introduction of a longer crankshaft and crankcase with a centre bearing, an increase in cylinder capacity, and a two-speed compressor. These changes allowed the engine to deliver 1,400hp at take-off and 1,300hp at 1,500m (1st gear) and 1200hp at 4000m (2nd gear). This came at the cost of a much increased total weight. It was expected that further development, such as the introduction of higher grade fuels, would lead to a power output of 1,660hp at low altitude.

With the Fall of France, engine development was stopped under the occupation. After the war, development recommenced; however production of this engine after 1945 was transferred to the newly formed SNECMA and the engine was renamed the SNECMA 14R.

Variants

 * 14R-04:Improved higher performance using 92 Octane fuel. 14N with 2-speed supercharge (6.5:1 and 9:1), LH rotation, 1590 hp for take-off.
 * 14R-05:RH rotation version of 14R-4.
 * 14R-08:RPM increased from 2,400 to 2,600 improving power output. LH rotation.
 * 14R-09:RH rotation version of 14R-08
 * 14R-24:LH rotation, 1600 hp.
 * 14R-25:RH rotation version of 14R-24.
 * 14R-26:LH rotation, 1600 hp.
 * 14R-27:RH rotation version of 14R-26.
 * 14R-28:LH rotation, 1600 hp.
 * 14R-29:RH rotation version of 14R-28.
 * 14R-32:LH rotation
 * 14R-100:
 * 14R-200:LH rotation
 * 14R-201:RH rotation
 * 14R-210:
 * 28T-1:28 cylinder, double 14R-24 engines placed back-to-back with co-axial contra-rotating propeller shafts, direct fuel injection, 2-speed supercharger, 77.4 L displacement, delivering 3200 hp for take-off using 100/130 octane fuel.