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As quoted in James Hollands "The War in the West; Germany Ascendant 1939-1941"-

The second was the Messerschmitt 110, which was a twin-engine fighter and originally conceived as a long-range bomber escort. It was a particular favorite of Goring, and so no one dared to tell him it had numerous deficiencies, not least a slow rate of climb and dive, and a lack of maneuverability, which meant that in a dogfight with a half-decent single-engine fighter it was likely to come out second best. So taken was [Goring] with the Me110 that he named it the 'Zerstorer" (Destroyer) and created special Zerstorer fighter wings, plucking many of the best fighter pilots from the single-engine units to pilot them. And again, over Poland and in Norway, where they faced no modern opposition, the myth surrounding their potency only grew.

There was, however, another single-engine fighter that could have offered a more effective support act to the Me109E. This was the Heinkel 112, which had been put forward as a fighter plane at the same time as the 109 and had initially performed even better. The Luftwaffe had ordered further prototypes of both and by the time Messerschmitt had developed the 109E, Heinkel's 112E had speeds of more than 350 mph, was considered highly maneuverable, had a sold, inward-folding undercarriage and elliptical wings, and had an astonishing range of more than 715 miles, which was significantly better than that of the Me119. Its rate of climb was not quite as good as the Me109E's, but it could still reach 20,000 feet in ten minutes, which was as good as anything else out there. When Heinkel protested the Udet that his fighter should be given a contract, he was firmly told to drop the matter, which he did; after all, remours of Jewish blood had always dogged Heinkel, so it paid not to kick up too much of a fuss, and, in any case, Udet and Messerschmitt were particularly good friends as well as the professor being a good party man. None the less, that a plane as good and versatile as the Heinkel 112 as rejected, especially with its incredible range, was astonishing. Range would be critical in fighting over Britain. For the Luftwaffe, this was unfortunate because the failure to back the Heinkel meant a truely winning combination had been passed over.

If this was the case, then how would the use of the He112 instead of the Me110 in the Battle of Britain and indead other theaters have effected the war in the air? Obviously this would not have single-handedly won the war for the Nazis but how much would the war in the air have changed?
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