Following the 1939 aerial Battle of the Heligoland Bight, RAF attacks shifted to the cover of darkness, initiating the Defence of the Reich campaign.

Each sector named a Himmelbett (canopy bed) would direct the night fighter into visual range with target bombers.

His victories increased to 17 by the end of 1943, including three British Avro Lancaster bombers shot down on the night of 25/26 June 1943.

Husemann was awarded the German Cross in Gold on 24 October 1943, and the Ehrenpokal der Luftwaffe on 1 November 1943.

On 4 January 1944, Husemann became commander of the I. Gruppe of Nachtjagdgeschwader 3 (NJG 3—3rd Night Fighter Wing), succeeding Hauptmann Paul Szameitat who had been killed.

Too low to bail out, Husemann made a forced landing in the fields of Tværmosegaard, a farm 9 kilometres (5.6 miles) northeast of Herning.