Avia Rk.12

Rk.12
Type	Seven-cylinder air-cooled radial
National origin	Czechoslovakia
Manufacturer	Avia (Avia akciova spolecnost pro prumysl letecky), Prague

One of 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.

As well as producing aircraft and building Hispano-Suiza and Lorraine aero-engines under licence, Avia also designed and built their own radial engines. Their Rk.12 was a seven-cylinder supercharged 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 pistons were also of heat-treated Y alloy. The crankcase was cast from aluminium alloy, with some minor parts using magnesium alloy. The single-throw, two-piece crankshaft 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.

Data from Jane's All the World's Aircraft 1938

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