Pobjoy Niagara

The Pobjoy Niagara is a British seven-cylinder, air-cooled, radial, aero-engine first produced in 1934. The design ran at higher speeds than conventional engines, and used reduction gearing to lower the speed of the propeller. This led to a noticeable off-centre mounting for the propeller. The Niagara was a popular engine for light and experimental aircraft,[1] well regarded due to its small diameter, smooth operation, low noise and innovative engineering.

Niagara
Pobjoy Niagara on display at the Science Museum, London
Type Piston radial aero engine
Manufacturer Pobjoy Airmotors
First run 1934

Variants

Niagara I
Bore/stroke 77 x 87 mm (3.03 x 3.43 in), swept volume 2,835 cc (173 cu in). Compression 6.25:1, gearing 0.47:1. Normal continuous power 84 hp (63 kW) at 3,200 rpm at sea level.[2]
Niagara II
Bore/stroke 77 x 87 mm (3.03x3.43 in), swept volume 2,835 cc (173 cu in). Compression 6.0:1, gearing 0.39:1. Normal continuous power 84 hp (63 kW) at 3,200 rpm at sea level.[2]
Niagara III
Bore/stroke 77 x 87 mm (3.03x3.43 in), swept volume 2,835 cc (173 cu in). Gearing 0.47:1. Normal continuous power 88 hp (66 kW) at 3,300 rpm at sea level.[2]
Niagara IV
Similar to Niagara III but with a higher operating rpm. Normal continuous power 98 hp (73 kW) at 3,500 rpm at sea level.[2]
Niagara V
Larger version of the basic Niagara. Bore/stroke 81 x 87 mm (3.19 x 3.43 in), swept volume 3,138 cc (191.5 cu in). Compression 8.0:1, gearing 0.47:1. Normal continuous power 125 hp (93 kW) at 4,000 rpm at sea level.[2][3]
Cataract I-III
De-rated, uncowled versions of Niagara I-III with simple inter-cylinder baffles for cooling and trickle-down lubrication for lower exhaust rockers. Compression 5.7:1, gearing 0.47:1.[2][3][4]
Cascade
Direct drive version of Cataract I. Normal continuous power 66 hp (49 kW) at 2,100 rpm.[4]

Applications

Niagara

Cataract

Cascade

Survivors

A Pobjoy Niagara powered Comper Swift G-ACTF that is owned and operated by The Shuttleworth Collection, Old Warden remains airworthy in 2017 and displays to the public at home airshows during the flying season.[5]

Engines on display

A preserved Pobjoy Niagara engine is on public display at the Science Museum (London).

Specifications (Pobjoy Niagara IV)

Data from Lumsden.[2]

General characteristics

  • Type: 7-cylinder, air-cooled, radial engine
  • Bore: 3.03 in (77 mm)
  • Stroke: 3.43 in (87 mm)
  • Displacement: 173 cu in (2.8 L)
  • Diameter: 26.5 in (673 mm)
  • Dry weight: 130 lb (59 kg)

Components

  • Valvetrain: 1 inlet and 1 exhaust valve per cylinder
  • Fuel system: 1 Claudel-Hobson carburettor
  • Fuel type: 70 octane
  • Cooling system: Air-cooled

Performance

See also

Related development

Comparable engines

Related lists

References

Notes

  1. Gunston 1989, p.111.
  2. Lumsden 2003, p.179.
  3. Jane's All the World's Aircraft p.26d
  4. Ord-Hume p.589
  5. www.shuttleworth.org Retrieved: 28 February 2017.

Bibliography

  • Grey, C.G. (1972). Jane's All the World's Aircraft 1938. London: David & Charles. ISBN 0-7153-5734-4.
  • Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN 1-85260-163-9
  • Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.
  • Ord-Hume, Arthur W.J.G. (2000). British Light Aeroplanes. Peterborough: GMS Enterprises. ISBN 978-1-870384-76-6.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.