Adjustable Pitch air screw (Baden-Powell)

This two-bladed 82 in (2.08 m) diameter propeller is an adjustable pitch type designed and constructed by Major Baden-Powell. As thrust output varies with pitch this propeller could be adjusted to match the engine characteristics. The blades are solid timber and fit into metal sleeves. The sleeves have elongated holes allowing the diameter and pitch of the propeller to be altered.