As well as producing aircraft and building Hispano-Suiza and Lorraine aero-engines under licence, Avia also designed and built their own radial engines. The Rk.17 was a 9-cylinder supercharged model, rated at 360 hp / 270 kW. It was a nine-cylinder version of their Rk.12.
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 heat treated silumin 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 eight piston rods.
Type: 9-cylinder air-cooled radial
Bore: 130 mm (5.12 in)
Stroke: 140 mm (5.51 in)
Displacement: 16.72 L (1,020 cu in)
Length: 1,065 mm (41.93 in)
Diameter: 1,184 mm (46.61 in)
Dry weight: 260 kg (573 lb) with ancillaries, without propeller hub
Valvetrain: one inlet and one exhaust valve per cylinder, operated by push-rods via rocker gear. Eight cam push-rod disc drive.
Supercharger: impeller drive ratio 10.7:1
Fuel system: single barrel Stromberg NAR80G carburettor
Ignition system: Scintilla magnetos, automatic advance
Fuel type: petrol, 85 Octane
Oil system: dry sump, with one pressure and one scavenging pump
Cooling system: air-cooled
Reduction gear: direct drive
Power output: rated maintained up to 2,750 m (9,000 ft), at 2,200 rpm 270 kW (360 hp)
Power output: maximum continuous at 2,200 rpm 300 kW (400 hp)
Power output: take-off at 2,020 rpm 330 kW (440 hp)
Compression ratio: 6.4:1
Specific fuel consumption: 255 g/(kW.h) (0.562 lb/(hp.h))
Oil consumption: 8.7 g/(kW.h) (0.23 oz/(hp.h))