In the latter half of WWII, the Luftwaffe Focke-Wulf Fw190 F series were the main aircraft used for air-to-ground assaults. The F-8, which entered the fray from the spring of 1944, was based on the A-8 aircraft and had the largest production numbers among the F series variants. The F-9 which had a superior engine output was also soon put into action. Both Fw190 F-8 and F-9 aircraft fought hard against the ever increasing numbers of Allied fighters up until the end of the war.