At the beginning of the Second World War, German military leadership did not prioritize specialized air-defense fighter aircraft. They believed anti-aircraft artillery would serve as the primary defense against aerial attacks on the Reich. However, large-scale nighttime raids by British aviation revealed that heavy anti-aircraft guns could not effectively protect ground targets. This necessitated specialized night-fighter units and a distinct tactical approach.
Since no aircraft were specifically designed for night combat at the time, the Luftwaffe initially used standard combat aircraft painted in dark colors—such as the Bf 109E-4 operated by Nachtjagdgeschwader 1 (the 1st Night Fighter Wing). For long-range interception of British bombers over British territory, they employed a specially converted Do 17 bomber designated the Do 17Z-10 Kauz II. The aircraft featured an infrared searchlight to help locate enemy aircraft in the night sky.
There are also documented cases of Fw 189 A-1 aircraft being used as night fighters after special modifications, including the installation of FuG 212 radar and an additional MG 151 cannon mounted for forward and upward firing.