An aircraft engine is used to power an aircraft. There are two dominant types of aircraft engines in use today: The piston engine and the jet engine. There are many variations of these two engine types that have developed throughout the course of aircraft history.
The piston engine is very much like the engine in the family sedan. It is comprised of pistons attached to connecting rods that spin a crankshaft. These are most commonly found on propeller-driven aircraft; however, not all propeller driven craft are piston powered. There are also turbo-prop engines. The other common aircraft engine is a jet engine. These engines use a compressor to create power in the form of high-pressure air being pushed out of the rear of the engine.
The first aircraft engine to use fuel was a piston engine. Early aircraft used liquid-cooled, flat-head automobile engines to power propellers. These engines were very heavy as they were constructed from heavy cast iron. They did not make much horsepower and the propeller speed was low. It was difficult, at best, for these engines to power the early aircraft and many pilots crashed due to engine failure.
Later aircraft were powered by radial piston engines. This design used a crankcase surrounded by individual cylinders arranged around the engine in a circle. This type of aircraft engine was air cooled and proved to be quite successful. These radial engines powered aircraft from early on until the end of World War II. Fighter planes as well as heavy bombers relied on the radial piston engine to power them through the skies.
The evolution of the aircraft engine took a huge step forward near the end or World War II with the Nazi's invention of the jet engine. The jet engine pushed aircraft much further into the performance arena than the piston engine could ever hope to achieve. This new engine went faster, climbed higher and outperformed anything that had ever been seen before it. The Allies were so afraid of the jet engine that practically all daylight bombing missions focused on jet engine production plants. Today, it is the engine of choice for nearly every large plane around the globe.
The aircraft engine took another step forward with the production of the turbo-jet engine. This aircraft engine uses a modified jet engine to turn a propeller. This engine has proved reliable and powers military and civilian planes around the world. Most recent major advancements in aircraft have involved the engine in one way or another. From fuel types to engine design, aircraft power plants have come a long way.