Boljanić airfield in Bosnia (called Bunar in ACRU documents) was the last airfield used by the Halyard mission. It was made after the Chetnik command with US missions withdrew to Bosnia. On November 1st, the airfield was used for the first time when 3 American pilots with members of Ranger mission were evacuated.
Halyard mission then proceeded further west in search of other downed Airmen, and in mid-December came back to Boljanić. Bad weather delayed rescue - clouds prevented planes from flying at low altitude, and grass runway was unusable due to heavy rain. For some time it was suggested that mission should go to partisan territory, and evacuate via Belgrade.
Since supplies were getting low, the ACRU B-26 plane was sent on Christmas to drop some material. On the day after the sky was clear, and low temperature froze runway so planes could land. On December 27, the remaining 20 US airmen with 11 other nationals and 2 members of the Halyard mission were evacuated.