12/31/2009. The Ro.37 was a two-seat fighter/reconnaissance biplane. Of mixed wood and metal construction, it was powered by a 560 hp Fiat A.30RA in-line engine. An improved Ro.37bis was developed subsequently, and this introduced an optional radial power plant comprising either the 600 hp Piaggio P. IX RC.40 radial engine. Production of the Ro.37 and Ro.37bis exceeding 160 and 475 respectively, of which 49 were exported to Afghanistan (16), Hungary (14), Uruguay (10), Austria (8), and Ecuador (1).