Already by 1933, Sagebiel had, at his brother's suggestion, come to be at the Deutsche Verkehrsfliegerschule ("German Commercial Flyers' School"), which was a front organization involved more with Germany's air force buildup than with commercial flying. As of 1934, he was being trusted with planning, as well as overseeing construction of, numerous Luftwaffe barracks (in Döberitz, Berlin-Gatow and Kladow, to name a few) as leader of the special works unit.
Sagebiel's austere building style, which when compared to Albert Speer's rather classicist tendencies came across as very stark and linear, was described as "Luftwaffe modern", owing to his close association with the Luftwaffe. With his earlier building of the Reich Air Transport Ministry for Hermann Göring, which came earlier than Albert Speer's exertion of influence on the National Socialists' architectural parlance, Sagebiel set a trend that would be recognizable throughout the Third Reich. From 1938, he was directly subordinate to the Air Transport Minister, Hermann Göring, and as a result was considered among the Reich's most important architects. In the same year, he became a professor at the Technische Hochschule Berlin.
The outbreak of war against the Soviet Union in 1941 put an end to all of Sagebiel's building plans.
Hans J. Reichhardt, Wolfgang Schäche: Von Berlin nach Germania. Transit Buchverlag, Berlin 2005 (gebundene Ausgabe), ISBN3-88747-127-X
Wolfgang Schäche: Architektur und Städtebau in Berlin zwischen 1933 und 1945. Gebr. Mann, Berlin 2002, ISBN3-7861-1178-2
Jost Schäfer: "Das ehemalige Luftkreiskommando IV in Münster von Ernst Sagebiel", in Zeitschrift Westfalen, 76. Bd. Münster 1999, S. 380-401. ISSN 0043-4337