Langley Propeller, Fixed-Pitch, Two-Blade, Wood and Fabric

Type: Two-Blade, Fixed-Pitch, Wood and Fabric

Diameter: 200.7 cm (79 in.)

Chord: 53.3 cm (21 in.)

Engine Application: None

Samuel P. Langley's conducted aerodynamic research in association with the design and construction of his model and full-size aerodromes. During the 1890s, Langley mounted a substantial aerodynamic research program at the Smithsonian. This research included tests using a large whirling arm approximately 8.5 meters in diameter located on Smithsonian grounds in a building known as the West Shed. This research appears to have been performed expressly to gather design data to construct the Langley flying machines. This was in contrast to Langley's earlier aerodynamic work that was purely theoretical research, published in his 1891 book, Experiments in Aerodynamics.

Tests showed Langley that helical propellers made from solid wood were more efficient than blades constructed with a frame over which cloth was tightly drawn. However, it was found that cost and ease of repair made the latter type more practical. Furthermore, at the size required for Langley's Aerodrome A, solid wood propellers were too heavy.