Messerschmitt Bf 109 11 July 1938 when Erhard Milch finally allowed Willy Messerschmitt to acquire the company. All Messerschmitt aircraft that originated after that date, such as the Me 210, were to carry the "Me" designation. Despite regulations by the RLM, wartime documents from Messerschmitt AG, RLM and "Luftwaffe" loss and strength reports continued to use both designations, sometimes even on the same page. All extant airframes bear the official "Bf 109" designation on their identification plates, including the final K-4 models. The aircraft was often referred to by the folk-designation, 'Me 109', particularly by the Allies. The aircraft was often nicknamed "Messer"
Willy Messerschmitt Robert Lusser, Messerschmitt designed the flagship product of the relaunched company, a low-wing four seater monoplane called the Messerschmitt M37, but better known by its later RLM designation of Bf 108. The following year, Messerschmitt would incorporate many advanced design features of this aircraft into the Bf 109 fighter. When in 1936, the Messerschmitt Bf 109 won the RLM's single-seat fighter contest to become one of the main Luftwaffe aircraft types, Messerschmitt and his factory took an important role in the RLM's armament plans, increasing in significance even further when Messerschmitt's Bf 110 also won the multi-purpose fighter contest. On