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 operational history is called "Tavallisesta kuriositeetiksi – Kahden Keski-Suomen Ilmailumuseon Messerschmitt Bf 109 -lentokoneen museoarvo" (From regular to a curiosity – The museal value of two Messerschmitt Bf 109s at the Central Finland Aviation Museum). Switzerland took delivery of the first of its 115 Bf 109s in 1938 when ten Bf 109Ds were delivered. After this, 80 109 E-3s were purchased which arrived from April 1939 until just before the German invasion of France in summer 1940. During the war, a further four 109s (two Fs and two Gs) were acquired by the Swiss Air Force through internment. The 109Es were supplemented