Close-up of the Tri-Motor Engine (1925)

An incredibly close, hazy air-to-air view focusing on the spinning propeller, exposed cylinders, and exhaust manifolds of a Ford Tri-Motor radial engine. — Close-up of the Tri-Motor Engine (1925) · Donald A. Hall Estate Collection

The three-engine Ford Tri-Motor was a major achievement in commercial aviation and Donald A. Hall took this photo in 1925 while he worked as an aerodynamics engineer at the Ford Aviation Division after the failed Stout aircraft mysteriously burnt to the ground. The plane was a stark contrast to the aerodynamic profile of Hall's own Spirit of St. Louis in 1927.