Keystone Army Airfield Keystone Army Airfield , was a World War II United States Army Air Forces airfield , located north - northwest of Keystone Heights , Florida . History . The airport was constructed in 1942 as Crystal Lake Airfield , and was commissioned in December 1942 as Keystone Army Airfield ( AAF ) by the United States Army Air Forces . It was used as part of the Air University ' s Army Air Forces School of Applied Tactics ( AAFSAT ) tactical combat simulation school in Central and Northern Florida . Kaystone AAF was assigned as a sub - base of Alachua Army Airfield , near Gainesville . Strategic Reconnaissance School . During the war , Keystone AAF was the home of the AAFSAT Strategic Reconnaissance School . The 432d Tactical Reconnaissance Group was moved in early March 1943 from Alachua as the Operational Training Unit ( OTU ) , although its component , 3d Tactical Reconnaissance Squadron was assigned to Keystone in January in an attached status from the AAFSAT Air Support Department . At Keystone , students flew the F - 3A Havoc ( a version of the A - 20 Havoc attack aircraft ) , and the P - 39D - 3 Reconnaissance version of the Aircobra fighter . The L - 2 and L - 3 Grasshopper light observation aircraft were also utilized . Pilots were trained in battlefield reconnaissance as well as long - range strategic reconnaissance photography , evasion techniques and other skills necessary for the unarmed combat reconnaissance missions to assist fighter , bombardment , and ground units . In November 1943 , the 313th Fighter Squadron was moved from Alachua with P - 40 Warhawk s . The 313th was part of the AAFSAT 50th Fighter Group which trained single - engine pilots in combat maneuvers . Crowded conditions at Alachua and the phasedown of the photo - reconnaissance school at Keystone were the reasons necessitating the move of the 313th . The 313th FS was upgraded to P - 47D Thunderbolt s in July 1943 . Phase - down of Keystone AAF began in late 1943 when the 432d was inactivated on 1 November 1943 , and the 3d TRS was moved back to Orlando AAB in early February 1944 . The 313th FS was moved back to Orlando in January in preparation for its parent 50th Fighter Group being sent to the European Theater of Operations ( ETO ) as an operational fighter group under Ninth Air Force . Closure . With the operational squadrons leaving , a caretaker unit was assigned and the flying mission at the airfield was reduced to the support of transient aircraft using Keystone for landings and cross - country flights . The number of personnel were reduced , being reassigned to other bases . In January 1945 , AAFSAT sent down orders to close the facility , and it was placed on inactive status on 1 February 1945 . Jurisdiction of the airfield was transferred to Air Technical Service Command ( ATSC ) , whose mission was the transfer of any useful military equipment to other bases around the country . Under ATSC , buildings and equipment were sold and any useful military equipment was transferred to other bases around the country . The base was declared as surplus in 1946 and was turned over to the War Assets Administration ( WAA ) for disposal and return to civil use . The City of Keystone Heights acquired the property from the federal government in 1947 .