Followup
The Big Week raids demonstrated that the Luftwaffe's best anti-bomber weapon, twin-engine Zerstörer designs like the Me 410 Hornisse, were appallingly vulnerable against Allied fighters. They were removed from service in the west, passing the defense role primarily to the higher performance single-engine designs.
Due to the effective protection offered by Allied fighters, a change of tactics was introduced: German fighters formed up well in front of the bombers, took a single head-on pass through the stream, and then left. This gave the defending fighters little time to react, and a few shells into the cockpit area could "destroy" a bomber in one pass. In a repeat of earlier RAF strategy, the Luftwaffe also attempted to form up their own version of the "Big Wing", which they hoped would allow them to bring the twins back into combat in the safety of huge number of covering single-engine designs. As had sometimes been the British experience, these formations proved extremely difficult to arrange.
Big Week bolstered the confidence of U.S. strategic bombing crews. Until that time, Allied bombers avoided contact with the Luftwaffe; now, the Americans used any method that would force the Luftwaffe into combat. Implementing this policy, the United States looked toward Berlin. Raiding the German capital, Allied leaders reasoned, would force the Luftwaffe to battle. Consequently, on March 4, the USSTAF launched the first of several attacks against Berlin. From England 730 bombers set out with an escort of 800 fighters. Fierce battles raged and resulted in heavy losses for both sides; 69 B-17s were lost but the Luftwaffe lost 160 aircraft. The Allies replaced their losses; the Luftwaffe could not.
Nevertheless, the new German strategies (using both heavily-armed Fw 190s as bomber destroyers, and Bf 109Gs to escort them) in the so-called Gefechtsverband formations were proving somewhat effective. The U.S. fighters, kept in close contact with the bombers they were protecting, could not chase down the attacking fighters before they were forced to turn around and return to the bombers. Lt. Gen. Jimmy Doolittle, commander of the 8th Air Force from the end of 1943, responded by "freeing" the fighters, allowing them to fly far ahead of the heavy bomber formations in an air superiority "fighter sweep" mode on the outward legs, then roam far from the bomber streams and hunt down the German fighters - especially the Sturmböcke Focke-Wulfs, from their limited maneuverability with their heavy cannons - before they could begin to approach the bombers. Though the change was unpopular with the bomber crews, its effects were immediate and extremely effective.
When the combined bomber offensive officially ended on April 1, 1944 and control of the strategic air forces passed to U.S. General Dwight D. Eisenhower, Allied airmen were well on the way to achieving air superiority over all of Europe. While they continued strategic bombing, the AAF turned its attention to the tactical air battle in support of the Normandy invasion.
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