The Pobjoy R is a British seven-cylinder air-cooled radial aircraft engine designed and built by Pobjoy Airmotors.[1] Introduced in 1926, it was a popular engine for ultralight and small aircraft in the 1930s. A notable feature of the Pobjoy R was the propeller reduction gear which allowed the small engine to operate at more desirable higher speeds.
| R | |
|---|---|
| |
| Preserved Pobjoy R at the Shuttleworth Collection | |
| Type | Piston radial aero-engine |
| Manufacturer | Pobjoy Airmotors |
| First run | 1926 |
| Major applications | BA Swallow Comper Swift |
The engine was license produced in Czechoslovakia by Walter Aircraft Engines as the Walter Mira.[2]
Variants edit
- Walter Mira R
- License produced version of Pobjoy R.
- Walter Mira I-R
- Renaming of Mira R.
- Walter Mira II-R
- Developed version of the Mira R producing 95 hp (70 kW).
Applications edit
- British Aircraft Swallow
- Comper Kite
- Comper Swift
- Cosmopolitan Light Plane
- Couzinet 101
- Farman F.239
- Fauvel AV.10
- Fieseler F 3
- General Aircraft Monospar
- Hendy Hobo
- Kay Gyroplane
- Landgraf H-2
- Letov Š-139
- Lippisch Delta IV
- Mauboussin M.121P Corsaire Major
- Miles Satyr
- Nicholas-Beazley Pobjoy Special
- Nozawa X-I
- Pander Multipro
- Praga E.214
- Přikryl-Blecha PB-5 Racek
- Savoia-Marchetti SM.80bis
- Short Scion
- Short Scion Senior
- Spartan Clipper
- Swanson-Fahlin SF-1
- Walter Mira
Engines on display edit
A preserved Pobjoy R engine is on display at the Shuttleworth Collection, Old Warden, Bedfordshire.[citation needed]
Two Pobjoy R engines, one installed in the remains of Comper Swift (R222 / LV-FBA) will be soon on display at the National Aviation Museum in Buenos Aires Province, Argentina.[citation needed]
Specifications (Pobjoy R) edit
Data from Lumsden.
General characteristics
- Type: 7-cylinder air-cooled, radial, left-hand tractor
- Bore: 3.03 in (77 mm)
- Stroke: 3.43 in (87 mm)
- Displacement: 173.05 cu in (2.84 L)
- Diameter: 25.5 in (647.7 mm)
- Dry weight: 135 lb
Components
- Oil system: Dry sump
- Cooling system: Air-cooled
Performance
- Power output: 85 hp
- Specific power: 0.5 hp/cu in
- Fuel consumption: 4.9 imp. gallons per hour
- Power-to-weight ratio: 0.63 hp/lb
See also edit
Related development
Comparable engines
Related lists
References edit
Notes edit
- ^ Lumsden 2003, p.178.
- ^ Letecvi magazine, (Walter engine range advertisement, 1935) 1934, Volume 10, No. 12 Retrieved: 27 November 2021
Bibliography edit
- Guttery, T.E. The Shuttleworth Collection. London: Wm. Carling & Co, 1969. SBN 901319-01-5
- Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.