It is believed this artifact is a 37 kW (50 hp) Curtiss E-4, operated at a lower than normal rotational speed. It was the first of Curtiss water-cooled engines, and the first of two engines to power the U.S. Army Signal Corps Dirigible No. 1, the first U.S. military airship. The engine drove a tubular steel shaft about 6.7 m (22 ft) long on which was mounted a wooden propeller designed by Lt. Thomas E. Selfridge.
In 1908, the Signal Corps awarded Thomas Baldwin a contract for the construction of an airship not to exceed 36.6 m (120 ft), to be completely maneuverable, and to obtain a speed of 32 km/hr (20 mph). Baldwin piloted the airship, and Glenn Curtiss was the engineer. In the official speed run, the Baldwin airship reached 31.38 km/hr (19.61 mph).
After service at Fort Meyer and Omaha, this engine was replaced by another Curtiss Model E-4 engine, also in the museum’s collection.
Display Status
This object is on display in Early Flight at the National Air and Space Museum in Washington, DC.
Object Details
Date
1908
Country of Origin
United States of America
Type
PROPULSION-Reciprocating & Rotary
Manufacturer
Curtiss Aeroplane and Motor Company
Designer
Glenn H. Curtiss
Physical Description
Type: Reciprocating, in-line, 4 cylinders, water-cooled
Power rating: 14.9 KW (20 hp) at 450 rpm
Displacement: 6.4 L ( 393 cu in.)
Bore and Stroke: 127 mm (5 in.) x 127 mm (5 in.)
Weight: 114 kg (250 lb)
Dimensions
Approximate: 91.4 × 61 × 91.4cm, 113.4kg (3 × 2 × 3 ft., 250lb.)
Support: 171.5 × 106.7 × 82.6cm (67 1/2 in. × 42 in. × 32 1/2 in.)
Materials
Metal
Wood
Coating
Inventory Number
A19310062000
Credit Line
Gift of Charles R. Witteman
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
For more information, visit the Smithsonians Terms of Use.