One of

Avia Avia Motors s.r.o. is a Czech automotive manufacturer. It was founded in 1919 as an aircraft maker, and diversified into trucks after 1945. As an aircraft maker it was notable for producing biplane fighter aircraft, especially the B-534. Avia ...

's own designs, the 1930s Avia Rk.12 was a seven-cylinder radial engine with a rated output of 150 kW (200 hp), built in Czechoslovakia.

Design and development

As well as producing aircraft and building

Hispano-Suiza Hispano-Suiza () is a Spanish automotive–engineering company. It was founded in 1904 by Marc Birkigt and Damian Mateu as an automobile manufacturer and eventually had several factories in Spain and France that produced luxury cars, aircraft en ...

and Lorraine aero-engines under licence, Avia also designed and built their own radial engines. Their Rk.12 was a seven-cylinder

supercharged In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorisation is that a supercharger is a form of forced induct ...

model, rated at 200 hp. It was a conventional air-cooled radial: nitrided steel barrels with integral fins were screwed into heat-treated Y alloy heads. The

piston A piston is a component of reciprocating engines, reciprocating pumps, gas compressors, hydraulic cylinders and pneumatic cylinders, among other similar mechanisms. It is the moving component that is contained by a cylinder and is made gas-tig ...

s were also of heat-treated Y alloy. The

crankcase In a piston engine, the crankcase is the housing that surrounds the crankshaft. In most modern engines, the crankcase is integrated into the engine block. Two-stroke engines typically use a crankcase-compression design, resulting in the fuel/a ...

was cast from aluminium alloy, with some minor parts using magnesium alloy. The single-throw, two-piece

crankshaft A crankshaft is a mechanical component used in a piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating shaft containing one or more crankpins, that are driven by the pistons via the connecting ...

was linked to the pistons with an I-section Y alloy master rod, with a single-piece big end, which carried the other six piston rods.

Applications

Avia 51 The Avia 51 was a 1930s Czechoslovakian six-passenger commercial transport, designed by Robert Nebesář and built by Avia. The type was uneconomical in use and only three were built. Development The Avia 51 was a three-engined high-wing cant ...

Specifications

References

{{Avia aeroengines 1930s aircraft piston engines Aircraft air-cooled radial piston engines