Instead of having an orthodox fixed cylinder clock with a rotating crankshaft, in the radial engine, the crankshaft remains stationary and the entire cylinder block rotates around it. The beauty of rotating such a large mass was an inherent large gyroscopic flywheel effect that was able to smooth out the power delivery and reduce vibration. Vibration had been such a serious problem on other conventional piston engine designs that heavy flywheels had to be added. Because the cylinders themselves functioned as a flywheel, rotary piston engines typically had a power-to-weight ratio advantage over more conventional engine designs.

Most rotary engine s were arranged with the cylinders pointing outwards from a single crankshaft, in the same general form as a radial, but there were also rotary boxer engines and even one cylinder rotaries.

Initially, rotary engines were mostly used in the aircraft industry. However, there were also a few cars and motorcycles that were produced with a rotary engine.

The major difference between the radial engine and the rotary engine is that radial engines have pistons that move in a reciprocating fashion that cause the crankshaft to rotate. In rotary engines, however, the crankshaft does not rotate. Instead, the cylinders that accommodate the reciprocating pistons will rotate around the crankshaft. For this reason, aviation rotary engines had their propeller attached to the rotating cylinder block.

Mazda rotary engines are perhaps the most well known rotary engines used to power some Mazda cars. The Rotary Mazda RX7 and RX8 boast performance that equals and betters many other sports cars made worldwide.We hope that helps answer the question ‘What is What is a Rotary Engine?’!

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