P.H. Spencer, Pacoima, CA, pilot since 1914, designed Privateer (see Amphibions Inc.), Spencer-Larsens, Republic Seabees and Trident TR-1, all variations of basic Spencer Air Car configuration. This developed into S-12 4-seater, final version being S-12E (1 August 1974), marketed by Spencer Amphibian Air Car Inc. (also sold as plans). On 15 July 1988 company sold to Robert F. Kerans.