Luftwaffe immediately started upgrading the aerodrome. They began by removing a hill at the east end of the runway, followed by an extension of the runway. Tveit was transformed with military structures built throughout the village. In the east a minefield was laid and several fuel tanks were built around the airfield. Two large hangars were built, along with a large number of sheds. In the course of the war the runway was extended to . The German military planned a large expansion of the airport from 1945, which would have included new aprons and would have obliterated the village. These plans were halted by the end of the war.