Aviation Piston Engines

An aviation engine is an engine specifically designed for the needs of the airborne environment.These engines advanced rapidly through the 20^th century, driven by the never ending need to fly a heavier, higher and faster aircraft with cargo, troops, passengers and/ or cargo to longer distances more economically.That was, and still is a really tough nut to crack, but certain advancements have occurred the past century that contributed to the engines we have today and the engines that are still in development. Here you will find a brief presentation of the engines used in most aircraft, up to today.

Most engine types will be presented briefly, and a more detailed and in depth analysis will come later.

This type of aviation engine has its cylinders lined up in one row. This is the most common configuration, and is in use throughout Europe and Asia in cars and light vehicles, so it comes naturally that they found their way in early aircraft. The main advantage of this engine, is that it allows the aircraft to be designed with a narrow frontal profile(Arrow type fuselage) reducing drag, but the airflow around the cylinder is really poor, so it has to be water-cooled. Water cooling means bad weight-power ratio, greater maintenance and risk of failure due to the complexity of the cooling system and the radiator(s) needed. Notable aircraft equipped with these engines: Wright flyer and almost all early aircraft.

NOT to be confused with Wankel engines. Those early aviation engines were brought to light, during the effort to make the fixed wing aircraft, a machine of war during the 1^st World War. By then it became apparent that inline aircraft engines were too heavy, and suffered by questionable reliability and numerous mechanical glitches. Aircraft designers needed an engine that had to be more light, more powerful, and far cheaper, and easier to manufacture in large quantities. The rotary engine ticked all the boxes for that time. The great deference was that the entire engine rotates together with the prop, providing airflow for cooling, regardless of the aircraft's forward speed. They were used almost exclusively on aircraft because of their awkward and bulky design. Notable aircraft equipped with these engines: 1^st WW aircraft

This aviation engine type is somewhat two in line engines welded together on a single crankshaft to form a Vshape. The cylinders in this engine are arranged in two in-line banks, tilted 30-60 degrees apart from each other giving twice the power for 1 1/2 of the weight and cost of a pair of engines. The vast majority of V engines are water-cooled, but the sear power overcame the added weight of the cooling system. Unfortunately water cooling made the fighter aircraft of WWII way more vulnerable to lucky bullet hits. Notable aircraft equipped with these engines: WW2 British Spitfire-USA P51 Mustang

This type of engine also found applications in automotive industry, trains,ships and boats manliy due to their great torque.

With one or more rows of cylinders arranged in a circle around a centrally-located crankshaft, this type of engine provided a very good alternative to the V piston engines, but it was way more complex. Each row had to have an odd number of cylinders to produce smooth and efficient running. Radials have only one crank, throw per row and a relatively small crankcase, contributing to a favorable power/weight ratio. Because the cylinder arrangement exposes a large amount of the engine's heat radiating surfaces to the air and tends to cancel reciprocating forces, radial engines tend to cool evenly and run smoothly. Notable aircraft equipped with these engines: Douglas DC3, Canadair CL215 water bomber

Some times called as flat or boxer engines. They have two banks of cylinders on opposite sides of a centrally located crankcase. The engines are either air cooled or liquid cooled depending on the design and the application, but air cooled versions is mostly preferred. This type of engines dominates the General aviation aircraft for over half a century. Their proven reliability, simplicity, easy maintenance and efficiency make them ideal for lighter aircraft and some turbocharged variations can develop up to 400 horsepower or even more. They can run on all types of fuels even mogas(Motor gasoline) making them the ideal engine for the car of the skies. Notable aircraft equipped with these engines: Cessna 152/172/182/210, Piper PA34/PA28/PA32/PA24,Tecnam 2006,Diamond DA20/40/42

The Wankel engine is about one half the weight and size of a traditional piston engine of equal power output, and way less complex. In aviation, the power to weight ratio is very important, making the Wankel engine a good choice. Most are Mazda 12A and 13B engines, removed from cars and converted for aircraft implications. This is a very cost effective alternative to certified aircraft engines, with power output from 120 to 380 hp at a fraction of the cost of a conventional engine. Another advantage of Wankel engines is that dew to its simplicity it can be overhauled in 1 working day, for a fraction of the cost of conventional engines because it lacks many parts the piston engines(valves, camshafts,driving belts etc) and resulting to way higher TBOs(Time between overhauls).

Also Mistral Engines is in the process of certification of a variation of Wankel engines so that they can be used in certified aircraft applications.