 Some intelligence source estimated that 500 MiGs were being operated by the 1st United Air Army.Although 77 Squadron RAAF had previously operated in Korea as a ground-attack unit, many of its pilots were veterans of World War II fighter units and it was expected that the Gloster Meteor would allow it to return to its previous role of interception.With 22 Meteors, 77 Squadron was attached to the USAF's 4th F-IW at Kimpo at the end of July.