In December 1974, Haig was appointed as the next Supreme Allied Commander Europe by President Gerald Ford replacing General Andrew Goodpaster and returning to active duty within the United States Army. General Haig also became the top runner to be the 27th U.S. Army Chief of Staff, following the death of Army Chief of Staff General Creighton Abrams from complications of surgery to remove lung cancer on September 4, 1974. However it was General Frederick C. Weyand who ultimately filled Abrams' position as Army Chief of Staff instead of General Haig.From 1974 to 1979 General Haig served as the Supreme Allied Commander Europe, the commander of NATO forces in Europe, and commander in chief of United States European Command. During his tenure as SACEUR, General Haig focused on transforming SACEUR in order to face the future global challenge following the end of the Vietnam War and the rise of Soviet influence within Eastern Europe. Haig focused on strengthening the relationship between the United States and NATO member nations and their allies. As a result several fleets of United States Air Force aircraft, such as the F-111 Aardvark from the Strategic Air Command, were relocated to U.S. Air Force bases located in Europe.