The first successful rotary engine is generally attributed to the American F.O. Farwell in 1896; but the French Gnome engine, developed by the Seguin brothers, was much more successful in bringing the rotary to a broad aviation market beginning in 1909. The original Gnome had two valves, with the inlet in the head of the piston and exhaust in the in the cylinder head. The monosoupape, as the name signifies, had only one valve in the cylinder head, eliminating a weak feature of the earlier design, and was the most numerous model during World War I.
This was the second type of rotary aircraft engine designed by the Seguins, and the artifact was to power an aircraft designed in 1910 by Charles M. Olmsted. It drove two pusher propellers through extension drive shafts and mitre gears. Scale model wind tunnel tests indicated that the design was practical, but lack of funds prevented completion of the Olmsted aircraft.
Display Status
This object is on display in Pre-1920 Aviation at the Steven F. Udvar-Hazy Center in Chantilly, VA.
Object Details
Date
Circa 1912
Country of Origin
France
Type
PROPULSION-Reciprocating & Rotary
Designer
Laurent Seguin
Louis Seguin
Manufacturer
Societe des Moteurs Gnome et Rhône
Physical Description
Type: Rotary, 7 cylinders, monsoupape, air-cooled
Power rating: 37 kw (50 hp) at 1,200 rpm
Displacement: 7.98 L ( 488.5 cu in.)
Bore and Stroke: 110 mm (4.33 in.) x 120 mm (4.73 in.)
Weight: 78 kg (172 lb)
Dimensions
Other: 33 x 31 x 38 x 42 x 39 1/2in. (83.8 x 78.7 x 96.5 x 106.7 x 100.3cm)
Approximate (Weighed with Stand by Cat Forklift): 132.5kg (292lb.)
Materials
Steel, Aluminum, Preservative coating
Inventory Number
A19660001000
Credit Line
Gift of the Family and Estate of Charles M. Olmsted. Ph.D.
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
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