The Messerschmitt Bf 109 were begun to use from 1940 in missions of fighters-bomber, carrying a bomb of 250 kg., while other variants as the Bf 109E-5 and E-6 were used as recognition fighters without cannons. The model Bf 109E-7 was a development of E-4/N, being able to take an engine for to be thrown instead of a bomb.
The German fighter was a little faster, was carrying cannons and could realize fall down that the English could not execute, however this one was any more manoeuvre. In spite of it, a disadvantage was revealed like decisive: its scarce autonomy come down to 80 minutes, was turning out to be fatal in combat against the English fighters, which besides were flying on its own air space, what was allowing fill up quickly. Going out from the French airports, after crossing the English Channel only it were having of 20 minutes to fight, for what many fighters sank in the sea on not having been able to return to its bases. Besides, its scarce radius of action was limiting its assaults to the southern zone of the British Isles. The principal mission entrusted Me 109, was to escort to the average bombardiers He 111, Do 17 and Ju 88, which were turning out to be very vulnerable without its support. Such a defensive mission turned out to be a strategic mistake, since they were forced to not separate of the bombardiers, which was reducing capacity of action against the English Spitfire.