When did the Luftwaffe lose air-superiority over the Reich?

Question

To me one of the many crucial stages of WWII was when the Luftwaffe were no longer able to mount serious resistance to the Allied bombing raids. While the effect of the raids if often debated, it certainly led to a shortage of fuel that compounded the situation as they could never recover as the lack of fuel led to a lack of trained pilots.

The Allies began concentrating on the Axis fuel supply and manufacturing industries around mid-1944 according to Wikipedia, was this the significant date?

Answer 1

According to Dr. Richard R. Muller in his December 2003 article in Air and Space Power entitled Losing Air Superiority: A Case Study from World War II, he argues that the Germans had definitively lost air superiority over Europe in fall of 1944. Here he describes the final hope of the Luftewaffe to regain control of the skies, and the unlikely nature of such a proposition to succeed,

Another proposal that has attracted postwar attention was Galland’s suggestion to mass some 2,000–3,000 German fighters for a knockout blow. His goal was to commit this force against an American bomber formation in order to “shoot down an approximate total of 400–500 four-engined bombers against a loss of about 400 aircraft and about 100–150 pilots.”5 A victory on this scale would cause the Americans to cease daylight penetrations, restoring air superiority at a single stroke. In Galland’s view, Hitler scuttled this potentially decisive action by earmarking his carefully husbanded fighter reserve for support of the Ardennes counteroffensive in December 1944.

One has reasons to doubt the potential effectiveness of the “Great Blow.” While the operation was in the planning stages, considerable portions of the fighter reserve engaged American formations, but even under favorable conditions, the Germans did not down a significant number of American aircraft.6 The standards of German fighter-pilot training were so low by fall 1944 that the bulk of the 2,000+ pilots participating in the proposed operation would have been incapable of operating effectively. In particular, the task of assembling and controlling such a large quantity of aircraft in a single operation was probably beyond the Luftwaffe’s capability in late 1944.