| Lambda | |
|---|---|
![]()  | |
| Gnome 7 Lambda as shown in a 1913 Gnome catalog | |
| Type | Rotary aero engine | 
| Manufacturer | Gnome et Rhône | 
| First run | c.1911 | 
| Major applications | Avro 504 Bristol Boxkite Bristol Scout  | 
| Number built | 979 (British production) | 
The Gnome 7 Lambda was a French designed, seven-cylinder, air-cooled rotary aero engine that was produced under license in Britain and Germany. Powering several World War I-era aircraft types it was claimed to produce 80 horsepower (60 kW) from its capacity of 12 litres (730 cubic inches) although recorded figures are lower.[1]
Just under 1,000 units were produced in Britain, the majority (967) by the Daimler Company of Coventry. A 14-cylinder variant was known as the Gnome 14 Lambda-Lambda.
In Germany Motorenfabrik Oberursel license-built the seven-cylinder engine as the Oberursel U.0 and later copied the 14-cylinder design and designated it as the Oberursel U.III.
Variants
- Gnome 7 Lambda
 - Seven-cylinder, single-row rotary engine.
 - Gnome 7 Lambda (long stroke)
 - Increased stroke of 145 mm (5.71 in) to raise the compression ratio to 3.87:1, and total displacement to 12.26 litres (748 cu in).
 - Gnome 14 Double Lambda
 - 14-cylinder, two-row rotary engine using Lambda cylinders. 160 hp (120 kW).
 - Motorenfabrik Oberursel U.0
 - German production of the Gnome 7 Lambda – had a 124 mm (4.88 in) cylinder bore and 140 mm (5.51 in) piston stroke for a total displacement of 11.52 litres (703 cu in), external diameter of 1.020 metres (40.16 in).[2]
 - Motorenfabrik Oberursel U.III
 - :German production of the Gnome 14 Double Lambda
 
Applications
List from Lumsden

Gnome 7 Lambda
- Avro 504
 - Blackburn Type I
 - Borel hydro-monoplane[3]
 - Blériot Parasol
 - Blériot XI
 - Bristol Boxkite
 - Bristol Gordon England G.E.3
 - Bristol-Coanda Monoplanes
 - Bristol Coanda T.B.8
 - Bristol Coanda P.B.8
 - Bristol Scout
 - Caudron G.III
 - Deperdussin Type B
 - Dunne D.8
 - Henry Farman F.20
 - Grahame-White Type XV
 - London & Provincial 4
 - Lowe Marlburian
 - Nieuport IVG
 - Nieuport 10
 - Nieuport-Macchi Parasol
 - Radley-England Waterplane
 - Royal Aircraft Factory B.E.3
 - Royal Aircraft Factory B.E.4
 - Royal Aircraft Factory B.E.8
 - Royal Aircraft Factory B.S.1
 - Royal Aircraft Factory S.E.2
 - Royal Aircraft Factory S.E.2
 - Royal Aircraft Factory S.E.4
 - Short S.37
 - Short S.38
 - Short S.41
 - Short S.60
 - Short S.70
 - Sikorsky S-7
 - Sopwith Gordon Bennett Racer
 - Sopwith Pup
 - Sopwith Sociable
 - Sopwith Tabloid
 - Sopwith Three-Seater
 - Vickers No.8 Monoplane
 
Gnome 14 Lambda-Lambda
- Avro 510
 - Royal Aircraft Factory S.E.4
 - Deperdussin Monocoque
 - Fokker D.III
 - Fokker E.IV
 - Paul Schmitt P.S.3
 - Short S.63
 - Short S.64
 - Short S.70
 - Short S.74
 - Short S.80
 - Short S.81
 - Short S.82
 
Survivors
An original Gnome 7 Lambda engine is installed in the Sopwith Tabloid replica aircraft on display in the Grahame-White hall of the Royal Air Force Museum London.[4]
Specifications (Gnome 7 Lambda)

Data from Lumsden.[1]
General characteristics
- Type: 7-cylinder, single-row, rotary engine
 - Bore: 124 mm (4.9 in)
 - Stroke: 140 mm (5.5 in)
 - Displacement: 11.8 L (720 cu in)
 - Length: 112 cm (44 in)
 - Diameter: 93 cm (37 in)
 - Dry weight: 96 kg (212 lb)
 
Components
- Valvetrain: Automatic centre-piston inlet valve, overhead exhaust valve (one each per cylinder)
 - Cooling system: Air-cooled
 - Reduction gear: Direct drive, right-hand tractor, left-hand pusher
 
Performance
- Power output: 50.3 kW (67.5 hp) at 1,250 rpm (maximum power)
 - Compression ratio: 3.75:1
 
See also
Comparable engines
Related lists
References
Notes
- 1 2 Lumsden 2003, p. 151.
 - ↑ "Obsah fóra :: Zbraně a vybavení :: Výzbroj, zbraňové systémy, vybavení a příslušenství :: Motory :: Letecké motory :: Pístové :: Německo (DEU) :: Oberursel U.0". valka.cz (in Czech). Retrieved July 19, 2013.
 - ↑ "The Borel Hydro-Monoplane". Flight: 450. 19 July 1913.
 - ↑ RAF Museum – Sopwith Tabloid replica history Retrieved: 11 November 2010.
 
Bibliography
- Lumsden, Alec. British Piston Engines and their Aircraft. Marlborough, Wiltshire: Airlife Publishing, 2003. ISBN 1-85310-294-6.
 
