 In February 1971 MACS-4 was withdrawn from Vietnam, however 20 Marines from the Squadron remained at Monkey Mountain to man the Marine Tactical Data Communications Center (TDCC), an automated facility which linked the Air Force and Navy aircraft tracking systems and antiair warfare direction.In March 1971 the USAF SIGINT facility was closed and its operations were moved to Thailand.The base has largely reverted to jungle although a modern radio tower has been built at the site.