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, well regarded due to its small diameter, smooth operation, low noise and innovative engineering.

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. ;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. ;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. ;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. ;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. ;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.Jane's All the World's Aircraft p.26dOrd-Hume p.589 ;Cascade :Direct drive version of Cataract I. Normal continuous power 66 hp (49 kW) at 2,100 rpm.

Applications

Niagara

* Aeroput MMS-3 * Airspeed Fleet Shadower * CLW Curlew *

Comper Kite The Comper Kite was a single-engined, two-seat touring monoplane built in the UK, derived from the contemporary Comper Streak racer. Only one was built. Design and development The Kite was created by redesigning the single-seat Comper Streak r ...

* Comper Swift * General Aircraft Monospar ST-25 * General Aircraft Fleet Shadower * Gribovsky G-25 *

Lambach HL.I The Lambach HL.1 was a one-off, simple tandem two seat trainer designed and built by members and ex-members of the Delft Student Aeroclub (DSA) in the Netherlands in the mid-1930s. Design and development When in the early 1930s members of th ...

* Moss M.A.1 * Pobjoy Pirate * Saro Shrimp * Shapley Kittiwake * Short Scion Senior *

Short Scion The Short S.16 Scion and Scion II were 1930s British two-engine, cantilever monoplanes built by Short Brothers and (under licence) by Pobjoy Airmotors and Aircraft Ltd. in Rochester, Kent between 1933 and 1937. Altogether 22 Scion/Scion II ...

* Short S.31 (half scale Stirling) * Spartan Clipper *

Westland CL.20 The Westland CL.20 (aka Cierva-Lepère C.31) was a two-seat autogyro designed and built by Westland Aircraft between 1934 and 1938. One flying prototype and six airframes were built, which had control problems and insufficient lift. Before th ...

Cataract

* British Klemm Swallow * Hafner A.R.III Gyroplane * Hendy Hobo * Pitcairn PA-22

Cascade

Autogiro AC-35 The Autogiro Company of America AC-35 was an early attempt to make a roadable aircraft in the United States during the 1930s. Although it was successfully tested, it did not enter production; a 1960s attempt to revive the aircraft in a non-roadab ...

Survivors

A Pobjoy Niagara powered Comper Swift G-ACTF that is owned and operated by

The Shuttleworth Collection The Shuttleworth Collection is a working aeronautical and automotive collection located at the Old Warden Aerodrome, Old Warden in Bedfordshire, England. It is the oldest in the world and one of the most prestigious, due to the variety of old ...

, Old Warden remains airworthy in 2017 and displays to the public at home airshows during the flying season.www.shuttleworth.org
Retrieved: 28 February 2017.

Engines on display

A preserved Pobjoy Niagara engine is on public display at the

Science Museum (London) The Science Museum is a major museum on Exhibition Road in South Kensington, London. It was founded in 1857 and is one of the city's major tourist attractions, attracting 3.3 million visitors annually in 2019. Like other publicly funde ...

Specifications (Pobjoy Niagara IV)

References

Notes

Bibliography

* * Gunston, Bill. ''World Encyclopedia of Aero Engines''. Cambridge, England. Patrick Stephens Limited, 1989. * Lumsden, Alec. ''British Piston Engines and their Aircraft''. Marlborough, Wiltshire: Airlife Publishing, 2003. . *

External links

Pobjoy Niagara at oldengine.org"A New Pobjoy Engine"
- article in ''Flight'' {{Pobjoy aeroengines

Niagara Niagara may refer to: Geography Niagara Falls and nearby places In both the United States and Canada *Niagara Falls, the famous waterfalls in the Niagara River *Niagara River, part of the U.S.–Canada border *Niagara Escarpment, the cliff ov ...

1930s aircraft piston engines Aircraft air-cooled radial piston engines