High Quality Content by WIKIPEDIA articles! The McDonnell XF-85 Goblin was an American prototype fighter aircraft conceived during World War II by McDonnell Aircraft. It was intended to be carried in and deployed from the bomb bay of the giant Convair B-36 bomber as a parasite fighter. The XF-85`s intended role was to defend bombers from hostile interceptors, a need demonstrated during World War II. Two prototypes were constructed before the program was terminated.