Bates Model 2 B Horizontally-opposed Engine


Display Status:

This object is on display in the Boeing Aviation Hangar at the Steven F. Udvar-Hazy Center in Chantilly, VA.

Bates Model 2 B Horizontally-opposed Engine

Collection Item Summary:

This engine was manufactured by the Bates Engineering Company of Chicago, Illinois, about 1910. It is believed to be a 19 kW (25 shp) Model 2 B. The engine had automatic intake valves and mechanically actuated exhaust valves.

Matthew B. Sellers, builder of the first Kentucky-manufactured aircraft, flew his first quadraplane from 1908 to 1913 powered by various 2-cylinder, horizontally-opposed engines. This Bates Model 2 B was one of these engines.

Collection Item Long Description:

Data Source

National Air and Space Museum


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

Credit Line

Gift of Matthew Bacon Sellers, Jr. and John Sellers.


  • Engine Case - Aluminum
  • Propeller Blade - Wood


Hub Depth: 5.2 cm (2.0625 in.), Shaft Hole Diameter: 4.4 cm (1.75 in.), Bolt Hole Diameter: 0.6 cm (0.25 in.), Hub Diameter: 11.7 cm (4.625 in.), Propeller Diameter: 56.1875 in. (142.7 cm)

Country of Origin

United States of America



Physical Description

  • Type: Reciprocating, Horizontally-opposed, 2 cylinders, air-cooled
  • Power: 19 kW (25 hp) at 1,200 rpm
  • Weight: 22 kg (49 lb)


PROPULSION-Reciprocating & Rotary

Inventory Number