The Wolseley Aries III or A.R.9 was a British nine-cylinder, air-cooled radial aero engine that first ran in 1933, it was designed and built by Wolseley Motors. Intended for the military trainer aircraft market few were produced as Wolseley withdrew from the aero engine market in 1936.
A larger capacity version was known as the Wolseley Scorpio, further enlarged versions, the Leo and Libra were test run but did not fly.
A.R.9 Mk I203 horsepower (151 kW).
A.R.9 Mk II205 horsepower (153 kW). Higher permissible rpm version of Mk I.
A.R.9 Aries Mk III225 horsepower (168 kW), low boost
supercharger fitted.
Scorpio I250 horsepower (186 kW), (230 bhp at 2,250 rpm), increased
bore (111mm x 120 mm) to give a displacement of 9,477 cc, increased
compression ratio. Reduction gearing.
Scorpio II and III250 horsepower (186 kW), designed to run on 87
octane fuel with 6.5:1 ratio.
Leo280 horsepower (209 kW), few details, not flown or produced.
Libra390 hp at 6,000 ft. 725 lbs (329 kg). Tested but not flown or produced.
Airspeed EnvoyHawker TomtitData from Lumsden
Type: 9-cylinder, single row, radial engineBore: 4.19 in (106 mm)Stroke: 4.75 in (120 mm)Displacement: 588.6 cu in (9.654 L)Length: 42 in (1,067 mm)Diameter: 41.25 in (1,048 mm)Dry weight: 510 lb (231 kg)Valvetrain: Overhead valveSupercharger: Single speed, geared induction fan, slight positive pressureFuel type: PetrolCooling system: Air-cooledReduction gear: Epicyclic spur geared, right-hand tractor, reduction ratio 0.629:1Power output: 225 hp (168 kW) at 2,475 rpm (maximum power)Specific power: 0.38 hp/cu in (17.4 kw/L)Compression ratio: 5.35:1Power-to-weight ratio: 0.49 hp/lb (0.72 kW/kg) 