gear gear gear

facebook instagram twitter youtube linkedin issuu wikipedia tripadvisor izi.TRAVEL GoogleArtsmini

Siemens & Halske Sh.IIIa
1917 - 1918



The counter-rotary Siemens & Halske Sh.IIIa engine represents the latest development of the rotary engine arrangement widely used for aircraft propulsion in the early period of aviation, from 1908 to 1918. Despite of some drawbacks, the Sh.IIIa was a technically advanced engines for its time, capable of remarkable performances in terms of maximum power output, specific fuel consumption and mass-to-power ratio. In September 1918, a Siemens-Schuckert D.IV equipped with the engine Sh.IIIa did record a remarkable performance for those times, reaching the altitude of 8100 meters from the ground in 36 minutes. Despite a total production of circa 2000 examples, realised by both Siemens-Halske and Rhemag Mannheim under license, only very few examples remain nowadays.

Technical specifications

ManufacturerSiemens & Halske AG, Berlin-Spandau, Germany, from 1917 to 1918
Chief designering. Franz Dinslage
DescriptionBi-rotary star aircraft engine with 11 cylinders, the cylinder block and propeller rotating united counterclockwise, crankshaft rotating clockwise
Stroke140 mm
Bore124 mm
Displacement18600 cm³
Compression ratio6.0 (super-compressed engine)
Power160 hp at 900 rpm above sea level; 200 hp at 950 rpm at sea level (for take-off and short time); 240 hp at 1000 rpm at sea level (maximum power); 200 hp at 1000 rpm at 2000 m (full throttle); 160 hp at 1000 rpm at 3700 m (min. altitude with full throttle under continuous operation)
Specific fuel consumption270 g/hp/h
Specific power10.8 hp/litre
Valvetrain system2 overhead valves per cylinder, operated by pushrods and rocker arms
Fuel feeding systemwith one single-barrel gasoline carburetor controlled by a sliding throttle
Ignition systemone spark plug per cylinder fed by two high-voltage magneto distributors
Cooling systemair-fed
Lubrication systemforced by a 2-cylinder reciprocating pump
Diameter1070 mm
Length1210 mm
Weight198 kg
Mass-to-power ratio0.99 kg/CV


Albatros D.XI (fighter)

Pfalz D.VIII (fighter)

Roland D.XVI (fighter)

Siemens-Schuckert D.II (fighter)

Siemens-Schuckert D.III (fighter)

Siemens-Schuckert D.IV (fighter)

Download Poster


 - Museo Motori UNIPA

 - Museo Motori UNIPA

 - Museo Motori UNIPA

 - Museo Motori UNIPA

 - Museo Motori UNIPA

 - Museo Motori UNIPA
Testi e immagini di Giuseppe Genchi
Sito realizzato da Pasquale Pillitteri