08/15/2008. Developed from the A-8, the A-12 was powered by the 690 hp Wright R-1820-21 Cyclone nine-cylinder air-cooled radial engine, and 46 (s/n 33-212 to 33-257) were ordered by the USAAC. Pictured is the first A-12 that was delivered to Wright Field, Ohio, on November 21, 1933. It was scrapped in October 1936.