Radial engine

Piston engine configuration

Radial engine

The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders "radiate" outward from a central crankcase like the spokes of a wheel. It resembles a stylized star when viewed from the front. The radial configuration was commonly used for aircraft engines before gas turbine engines became predominant.

From Wikipedia, under CC BY-SA. More on occurri.