Clark Air Base, former U.S. military air base, central Luzon, Philippines. It covered an area of about 12 square miles (30 square km) and was located 48 miles (77 km) north of Manila near the foothills of the Cabusilan Mountains.
It was first established as a U.S. military camp for the 5th Cavalry after the Spanish-American War (1898). The base was named Clark Field in 1918 for Major Harold M. Clark, a pre-World War I pilot. On December 8, 1941, at the outset of the Pacific phase of World War II, the installation was the principal target of raids by Taiwan-based Japanese bombers that destroyed more than half of the U.S. Army’s aircraft in East Asia. After the Japanese occupied the Philippines (1941–42), the airfield became a major Japanese base of operations during the war. The first Japanese kamikaze (suicide) flight was made from Clark in 1944 as U.S. forces began the process of recapturing the Philippines. In the post-World War II era, Clark Air Base became the largest U.S. military air base outside the United States and a vital connecting link with U.S. forces in South Korea and, later, Southeast Asia. During the Vietnam War (1955–75), Clark Air Base served as a strategic supply base and fighter-squadron installation.
Beginning in the 1970s, the United States and the Philippines held negotiations on the conditions for continued U.S. use of Clark Air Base. The eruption in June 1991 of nearby Mount Pinatubo covered the base with volcanic ash, destroying many buildings. At that point, the negotiations over Clark Air Base became moot, and the U.S. government withdrew, turning over the base to the Philippine government on November 26, 1991. The Philippine government subsequently converted the air base and the surrounding area into a free port and a special economic zone, known as the Clark Freeport Zone. The industrial and transportation facilities developed there attracted foreign trade and investment, thereby stimulating the economic growth of central Luzon. The base’s runways and other facilities were converted for use as an international airport.