The Focke-Wulf Fw 190 Würger was a single-seat, single-engine fighter designed by Nazi Germany in the late 1930s and built by the Focke-Wulf aircraft factory in Bremen. It is one of the few German single-engine fighters to have used both liquid-cooled and air-cooled engines (in different versions). It was used by the Luftwaffe during the Second World War, and the F-8 was modified from the A-8 with a modified booster to enhance low altitude performance. Nearly a dozen F-8s were used as test platforms for anti-tank weapons, including the WGr.28 280 mm air-to-surface missile based on the Nbw 41 Heavy Intensive Land Rocket, the 88 mm (3.46 in) Panzerblitz 1 and R4. Panzerblitz 1 and R4M rockets - with several Rüstsatz performance upgrades developed for the F-8 - are available.