Guam. VR-11 became the largest squadron in the Navy with 700 pilots, 89 R5Ds and 10 R4Ds. NATS relied heavily on personnel with airline experience. At one time, VR-11 had 47 officers and 10 enlisted men that previously worked for 15 different airlines. One of VR-11's special missions was the delivery of whole blood to Pacific battle areas. Using special refrigerating units, the squadron was delivering 1000 pints a day by the invasion of Iwo Jima. Post-war, 1945–48 Following the war, the size of NATS diminished. The major operations at Miami and Olathe were eventually shutdown and the operations at San Francisco and Hawaii greatly reduced. The Naval Air Ferry Command was disbanded. By 1947, the NATS inventory had been reduced to only 116 aircraft. NATS meanwhile had planned for the future and introduced a new aircraft in 1947, the Lockheed R6O (later R6V) Constitution. Design of the Constitution had begun in 1942 for the Navy and Pan American. The Constitution featured a double deck cabin with a passenger capacity of 168 and was powered by four Pratt and Whitney R-4360s. Only two Constitutions were built for the Navy since Pan Am had previously dropped out of the project. The R6V remains to this day as the largest aircraft operated by the Navy. Defense department In 1948, the newly created Defense Department, with economy and efficiency as its goal, combined the Air Force's Air Transport Command and NATS into the Military Air Transport Command or MATS. The Navy's contribution to MATS consisted of five squadrons and 58 aircraft. Although NATS was dissolved, the Navy was allowed to retain several transport squadrons for its specific needs. The Navy contribution to MATS and its subsequent command, Military Airlift Command or MAC, lasted until 1967. The demands of the Vietnam War and the resultant pilot shortage caused the Navy to withdraw its commitment. References James Lee, Operation Lifeline – History and Development of the Naval Air Transport Service, 1947, Ziff-Davis Publishing Company Stanley M. Ulanoff, MATS: The Story of the Military Air Transport Service, 1964, The Moffa Press, Inc. Nicolas M. Williams, 'Aircraft of the United States' Military Air Transport Service', 1999, Midland Publishing Limited Melvin L. Shettle, Jr., 'United States Naval Air Stations of World WAR II – Volume One -Eastern States', 1995, Schaertel Publishing Co Melvin L. Shettle Jr., 'United States Naval Air Stations of World WAR II – Volume Two-Western