Corrected entry: Capt. Jack Harkness introduces himself as "American Volunteer, 133 Squadron, Royal Air Force". It is an historical fact that there was such a squadron, made up of American volunteers.but it was not formed until August 1941. The events in "The Empty Child" and "The Doctor Dances" are supposed to have taken place during the "Blitz" on London, which lasted from October 1940 to May 1941. Capt. Jack could not be a member of an RAF squadron that didn't yet exist.