The President of the United States of America, authorized by Title 10, Section 8742, United States Code, takes pride in presenting the Air Force Cross (Posthumously) to Major William Walter McAllister (AFSN: 0-1911665), United States Air Force (Reserve), for extraordinary heroism in military operations against an opposing armed force while serving as Pilot of an O-2 aircraft with the 21st Tactical Air Support Squadron, Qui Nhon Air Base, Vietnam, in action over the Republic of Vietnam on 9 and 10 March 1965. On these dates, acting as a Forward Air Controller under extremely adverse weather conditions and at night, he directed numerous air strikes in support of the Vietnamese Marines and their three American advisors. With complete disregard for his own safety, Major McAllister sought out targets ahead of the advancing Marines while under prolonged periods of hostile ground fire at dangerously low altitudes. Through his personal efforts, two American casualties were evacuated and the entire Marine unit effectively assisted in obtaining and securing their objectives. He also flew under extremely hazardous conditions under a low ceiling at night in mountainous terrain in an effort to assist friendly positions. Through his extraordinary heroism, superb airmanship, and aggressiveness in the face of hostile forces, Major McAllister reflected the highest credit upon himself and the United States Air Force.