is a joint Japan-US naval air base located in the cities of Yamato and Ayase in Kanagawa, Japan. It is the largest United States Navy (USN) air base in the Pacific Ocean and once housed the squadrons of Carrier Air Wing Five (CVW-5), which deploys with the American aircraft carrier . During 2017 and 2018 the fixed-wing aircraft of CVW-5 relocated to Marine Corps Air Station Iwakuni in western Japan. CVW-5 shares the base with the Headquarters Fleet Air Force and Fleet Air Wing 4 of the Japan Maritime Self-Defense Force (JMSDF). NAF Atsugi is also home to Helicopter Maritime Strike Squadron 51 (HSM-51), which provides detachments of MH-60R helicopters to forward deployed U.S. Navy guided missile cruisers, guided missile destroyers and frigates homeported at the nearby Yokosuka Naval Base. Service members stationed at Atsugi also work in conjunction with the former Kamiseya Naval Radio Receiving Facility. Despite its name, the base is east northeast from the city of Atsugi, and is not adjacent to the city. History The Imperial Japanese Navy constructed the base in 1938 to house the 302nd Kokutai, one of the Navy's most formidable fighter squadrons during World War II. Aircraft based at Atsugi shot down more than 300 American bombers during the firebombings of 1945. After Japan's surrender, many of Atsugi's pilots refused to follow Emperor Shōwa's order to lay down their arms, and took to the skies to drop leaflets on Tokyo and Yokohama urging locals to resist the Americans. Eventually, these pilots gave up and left Atsugi. General Douglas MacArthur arrived at Atsugi on 30 August to accept Japan's surrender. Shortly afterwards, elements of the USAAF 3d Bombardment Group moved in about 8 September, being replaced by the USAAF 49th Fighter Group on 15 September which handled the initial cleanup of the heavily damaged airfield along with the 1539th Army Air Forces Base Unit to provide station facilities. Minimal flight operations were restored by October which allowed the P-61 Black Widow-equipped 418th Night Fighter Squadron to operate from the airfield to provide air defense over the area, along with the P-38 Lightnings of the 49th FG. The 49th moved to Chitose Airfield on Hokkaido in mid February 1946, the 418th NFS to Okinawa in June, and on 31 December 1946 the 1539th AAFBU moved to Haneda Airfield. During the occupation, the base housed the overflow from nearby Camp Zama; it was not refurbished