two Klimov 1,100 hp M-105R engines
Alexander Arkhangelsky was second in command at the Tupolev OKB when Andrei Tupolev was imprisoned. During Tupolev's absence, he was authorized to append his name to the SB variants.
The Ar-2 an attempt to improve the SB design. The major airframe changes made on the Ar-2 were streamlining of the engine cowl, higher power engines , completely new outer wing panels of greater span and taper, and a new nose. The engine cooling system was moved inside the wings, with air inlets on the leading edges and exits on the underwings. Dive brakes were added to allow for the type's new role as a dive bomber.
