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 JG 26 was equipped with the Bf 109 E-4/N model of improved performance, powered by the new DB 601N engine using 100 octane aviation fuel. The fuel-injected DB 601 proved most useful against the British Supermarine Spitfire and Hawker Hurricane, as the British fighters used gravity-fed carburetted engines, which would cut out under negative "g"-forces whereas the DB 601 did not. The Bf 109s thus had the initial advantage in dives, either during attack or to escape, in that it could 'bunt' directly into a dive with no loss of power. Another difference was the choice of fighter armament: the