The Rolls-Royce Buzzard (also referred to as the H engine) was a British piston aero engine of 36.7 litres (2,240 cubic inches) capacity that produced about 800 horsepower (600 kW). Designed and built by Rolls-Royce Limited it featured 12 cylinders in a 'V' configuration of 6 in (150 mm) bore and 6.6 in (170 mm) stroke. It was manufactured in the late 1920s, but only 100 were sold. A further development was the Rolls-Royce R Schneider Trophy engine. The Buzzard was developed by scaling-up the Kestrel engine in the ratio of 5:6.
List from Lumsden.
Buzzard IMS, (H.XIMS)
(1927), Maximum power 955 hp (712 kW), nine engines produced at Derby.
Buzzard IIMS, (H.XIIMS)
(1932-33), Maximum power 955 hp (712 kW), reduced propeller drive ratio (0.553:1), 69 engines produced at Derby.
Buzzard IIIMS, (H.XIVMS)
(1931-33), Maximum power 937 hp (699 kW), further reduced propeller drive ratio (0.477:1), 22 engines produced at Derby.
Blackburn Iris
Blackburn M.1/30
Blackburn Perth
Handley Page H.P.46
Hawker Horsley
Kawanishi H3K
Short Singapore I
Short Sarafand
Vickers Type 207
Data from Lumsden
Type: 12-cylinder liquid-cooled Vee aircraft piston engine
Bore: 6 in (152.4 mm)
Stroke: 6.6 in (167.6 mm)
Displacement: 2,239.3 in³ (36.7 L)
Length: 75.7 in (1,923 mm)
Width: 30.6 in (777 mm)
Height: 44.4 in (1,128 mm)
Dry weight: 1,140 lb (517 kg)
Valvetrain: Overhead camshaft
Supercharger: Single-stage supercharger
Fuel type: 73-77 octane petrol
Cooling system: Liquid-cooled
Power output: 800 hp (600 kW)
Specific power: 0.36 hp/in³ (16.3 kW/L)
Compression ratio: 5.5:1
Power-to-weight ratio: 0.7 hp/lb
