After the success of the simulation titles Their Finest Hour: The Battle of Britain® and Battlehawks 1942 in the late 80s, LucasArts decided to follow up those games with another World War II simulation title: Secret Weapons of the Luftwaffe. Released in August 1991, the game followed the campaign by the US 8th Air Force to cripple the German Luftwaffe during the final years of World War II. Players could fly in either American or German warplanes. The game was remarkable because many of the playable airplanes were still under development during the war. In other words, the planes were never used extensively in battle, so players could explore “what if ” possibilities with the game. Those possibilities were further expanded by four Tour of Duty expansion packs. The planes in those expansions included the P-38 Lighting, a twin-engine escort fighter and the German Do335, an interceptor aircraft that featured a conventional tractor propeller in the nose as well as a pusher propeller behind the tail of the aircraft.