In March 1954, Pope left the U.S. Air Force and joined a CIA front organization, Civil Air Transport (CAT), flying one of its Fairchild C-119 Flying Boxcars to supply French forces besieged in the Battle of Điện Biên Phủ in French Indochina. On March 13, Việt Minh artillery disabled Điện Biên Phủ's airstrip, forcing the French garrison there to be supplied by air drop. CAT pilots flew hundreds of sorties from Cat Bi to Điện Biên Phủ. On May 6, 1954, the day before the French force surrendered, Pope was co-pilot of the lead aircraft in a group of six C-119s that made the last air drop to the besieged garrison.