California World War II Army Airfields During World War II , the United States Army Air Forces ( USAAF ) established numerous airfields in California for training pilots and aircrews of USAAF fighters and bombers . Overview . Most of these airfields were under the command of Fourth Air Force or the Army Air Forces Training Command ( AAFTC ) ( A predecessor of the current - day United States Air Force Air Education and Training Command ) . However the other USAAF support commands ( Air Technical Service Command ( ATSC ) ; Air Transport Command ( ATC ) or Troop Carrier Command ) commanded a significant number of airfields in a support roles . A significant number of them had operational squadrons for air defense of the Pacific coastline and anti - submarine patrols , and one was even handed over to Civil Air Patrol pilots for their use . In addition to the major fields , dozens of minor auxiliary fields and airstrips were built , generally to provide more room for basic flight training , but also to support other operations . A few of these were designed as " fallback fields " for launching defensive operations in case of a Japanese invasion . Most Army airfields were built with three runways in a triangle , with parking ramp areas adjacent to one runway . This triangular configuration allowed rapid construction , without regard to the direction of the prevailing winds . Navy fields were generally built with two runways in a cross , with a third runway intersecting the other two at an angle . There were , of course , other designs , including single - runway fields . Most noteworthy were " landing mats , " large concrete squares , hexagons and circles , which allowed takeoffs and landings in any direction . Following the war , many bases and auxiliary fields were given to local governments — or returned to service — as municipal airports . Often , budget constraints caused the new owners to close or even remove the " extra " runways , retaining only those that faced into the prevailing winds . In at least one case ( Orland ) , large portions of a landing mat were removed , leaving a conventional runway and ramp . Several fields were retained as United States Air Force installations and were front - line bases during the Cold War or used for experimental aviation , the most notable of these being Edwards Air Force Base . A few were sold or given back to private owners , generally to be returned to agricultural use , while a handful have become private airports . A number of fields were simply abandoned , due to their remote locations , and the remains of these can still be found , especially in the Mojave Desert . It is still possible to find remnants of these wartime airfields . Many were converted into municipal airports , some were returned to agriculture and several were retained as United States Air Force installations and were front - line bases during the Cold War . Hundreds of the temporary buildings that were used survive today , and are being used for other purposes . Major Airfields . Fourth Air Force . The mission of Fourth Air Force was the air defense of the West Coast , operating two air defense wings in California ( Los Angeles and San Francisco ) . It also provided operational training of newly formed groups and squadrons in combat aircraft prior to their deployment to overseas combat theaters . After April 1944 , operational training was changed to replacement training of newly commissioned pilots in combat fighters from the AAF Training Command advanced flying schools . AAF Training Command . Training Command airfields in California provided Primary , Basic and Advanced ( both single and multi - engine ) pilot training under the Army Air Force Flying Training Command . Mather AAF provided Navigator Training . Training Command also provided technical aircraft support training to both enlisted and officer personnel at aircraft delivery fields , operated by manufacturers such as North American , Douglas , Northrup , Lockheed and Consolidated Aircraft . Santa Ana AAB provided basic indoctrination training to new enlisted personnel and also pilot qualification screening for prospective air cadets . AAF Contract Flying Schools . Private flying schools operated under contract by Flying Training Command , providing primary pilot training to new air cadets . Although training was provided by civilian contractors and instruction was provided by civilian instructors , the schools were commanded by military personnel and were operated as a military base . These schools operated from early 1942 until being phased out in mid - 1944 . Graduates then advanced to regular Training Command flight schools for Basic and Advanced training . Air Transport Command . Airfields were used for transport of personnel , supplies and equipment . Also for ferrying replacement aircraft to overseas units ( Primarily Pacific Theater and Alaska ) . Technical Service Command . Provided aircraft modification prior to overseas deployment and also depot - level repair and maintenance services . Technical Service Command also operated acceptance centers for newly manufactured aircraft in Southern California , then ATC Ferrying Command transferred the new aircraft to various airfields or modification centers prior to deployment to operational units .