Bristol Phoenix

The Phoenix was an experimental version of the Bristol Aeroplane Company's Pegasus engine, adapted to run on the Diesel cycle. Only a few were built between 1928 and 1932, although samples fitted to a Westland Wapiti held the altitude record for diesel-powered aircraft at 27,453 ft (8,368 m) from 11 May 1934 until World War II.^[1] The primary advantage of the Phoenix was better fuel efficiency at cruise, by up to 35%.

Phoenix
Type	Diesel aircraft engine
Manufacturer	Bristol Aeroplane Company
First run	1928
Major applications	Westland Wapiti

Variants

• Phoenix I: Diesel version of the Pegasus IF, 380 hp.
• Phoenix IIM: Medium-supercharged diesel version of Pegasus IM, 470 hp.

Applications

• Westland Wapiti

Specifications (Phoenix I)

Data from Lumsden^[2]

General characteristics

• Type: nine-cylinder air-cooled Diesel radial engine
• Bore: 5.75 in (146 mm)
• Stroke: 7.5 in (190 mm)
• Displacement: 1,753 in³ (28.7 L)
• Length: 43.75 in (1,111 mm)
• Diameter: 55.25 in (1,403 mm)
• Dry weight: 1,067 lb (484 kg)

Components

• Valvetrain: Overhead valve, two intake and two exhaust valves per cylinder, pushrod-actuated.
• Fuel type: Diesel
• Cooling system: Air-cooled

Performance

• Power output: 380 hp (283 kW) at 2,000 rpm at sea level
• Specific power: 0.22 hp/in³ (9.9 kW/L)
• Compression ratio: 14:1
• Power-to-weight ratio: 0.36 hp/lb (0.6 kW/kg)

See also

Comparable engines

• BMW 114-V4
• Packard DR-980

Related lists

• List of aircraft engines