The spray pipes are still in place below the wing trailing edge on this late 1950s crop duster that was at the root of the Thrush agricultural aircaft family tree. Snow Aeronautical was bought by Rockwell in 1965, which mr. Snow left in 1972 to found Air Tractor that produced another family of famous spraying aircraft and derivatives.

Designed as a crop-duster in 1958 and leading on to a whole series of agricultural aircraft from the Rockwell, Ayres and Thrush family. The company's founder, Leland Snow, left Rockwell in 1972 to found Air Tractor, which is still producing similar agricultural aircraft, some of which have been adapted to be marketed in the close air support role.

Leland Snow's Thrush ag plane first flew in 1956. The S-2 and S-2A were in production by 1959. Snow sold his company to Rockwell-Standard in 1965. Later resigning, Mr. Snow developed a new design christened Air Tractor, first produced as the AT-300. This 1959 S-2A (Snow Aeronautical's 25th aircraft built) was restored by Airtractor Aircraft over eleven years.

Ag sprayer of the fifties on display at the Pima Air Museum. Designed by Leyland Snow, who went on to found the Air Tractor company.