I had an Uncle that was an aircraft mechanic in the USAAF in WW2 . His job was to repair downed salvageable aircraft behind enemy lines , then they would drop an air crew to fly it out . My mother gave me some of his old field reports that my dad had . One was in Yugoslavia , there were two downed B-24s , one was used for parts , the other was repaired . He and his group were being assisted by Yugo partizans , he said you had to watch yourself , so even back then it was a place of many factions . Makes interesting reading , I didnt know we did that . As for the B-24 ? that mission was a wash , they had to burn it , as the Germans caught wind of the activity .