Clement V-2 Engine


Display Status:

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.

Collection Item Summary:

This French engine powered the Santos-Dumont Airship No. 9 in 1903. It performed two tasks: propulsion and the operation of a belt driven blower to pressurize the airship's envelope. Although designed for the Clement Autocyclette motorcycle, it was easily converted to aeronautical use because of its light weight and adequate power.

Alberto Santos-Dumont, a wealthy Brazilian based in Paris, first became famous by flying his dirigible No. 6 around the Eiffel Tower in 1901 and, in 1906, made the first airplane flight in Europe. This artifact was of special interest because it had "connected with it the smallest motor which has ever been successfully applied to a dirigible balloon." From the accession file, it appears that Airship No. 9 was to be flown at an exhibition in St. Louis in 1904, but was vandalized and not flown again.

Collection Item Long Description:



Inventory Number


Physical Description

  • Type: Reciprocating, 2 cylinders, air-cooled
  • Power rating: 2.237 kW (3 hp) at 1,000 rpm
  • Displacement: 0.36 L (21.8 cu in)
  • Bore and Stroke: 5.72cm (2.25 in.) x 6.99 cm (2.75 in.)
  • Weight: 12.0 kg (26.4 lb)

Credit Line

Gift of Edward C. Boyce


Country of Origin



Metal, wood, leather


3-D: 81.3 × 63.5 × 76.2cm (32 × 25 × 30 in.)

Data Source

National Air and Space Museum

Restrictions & Rights

Do not reproduce without permission from the Smithsonian Institution, National Air and Space Museum


PROPULSION-Reciprocating & Rotary