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"
Messerschmitt Bf 109 a practice that was also used for other German aircraft designs. The G-6 variant was nicknamed by "Luftwaffe" personnel as "Die Beule" ("the bump/bulge") because of the cowling's characteristic, bulging covers for the breeches of the 13 mm (.51 in) MG 131 machine guns, with the separate "Beule" covers eliminated by the time of the G-10 model's introduction of a subtly reshaped upper cowling. In July 1937, not long after the public debut of the new fighter, three Bf 109Bs took part in the Flugmeeting airshow in Zürich under the command of Major Seidemann. They won in several categories: First