August 1990 and Operation Desert Storm in January 1991. The first combat sortie of Desert Storm was launched from Barksdale, when seven B-52Gs flew a 35-hour mission – the longest combat sortie in history at that time – to fire a barrage of conventional air-launched cruise missiles against Iraq. The B-52s from Barksdale that were deployed to Morón Air Base, Spain (a former SAC "Reflex" base) dropped 10 percent of all U.S. Air Force bombs during the Persian Gulf War. Post-Cold War Upon its return from the Middle East, the 2nd Bombardment Wing, Heavy was redesignated the 2nd Wing with its implementation of the objective wing organization on 1 September 1991. The base turned its attention from combat to more peaceful pursuits when two B-52s, a KC-10 and their crews visited Dyagilevo Air Base, Russia, in March 1992. In May 1992, Barksdale hosted a return visit by two Russian Tupolev Tu-95 "Bear" bombers, an Antonov An-124 "Condor" transport and 58 Russian airmen. The Russians stayed for six days, seeing a slice of America and participating in Strategic Air Command's final Bombing and Navigation Competition awards symposium. The Russians visited again in August 1994, bringing a Tu-95 "Bear" and an Ilyushin Il-78 aerial tanker. Barksdale began a friendship with Ukrainian Air Force airmen later in 1994, when a B-52 and KC-10 visited Poltava Air Base, Ukraine. In April 1992, 265 buildings on Barksdale's main base were placed on the National Register of Historic Places. The area from the Shreveport Gate to the flightline and from the Bossier Gate to Hoban Hall make up the Barksdale Field Historic District, along with much of family housing. On 1 June 1992, Barksdale was transferred from the inactivating Strategic Air Command to the newly activated Air Combat Command (ACC). All active-duty aircraft assigned to Barksdale were assigned ACC tail codes of "LA". An equipment change began also in 1992 when the 596th Bomb Squadron retired its B-52Gs and replaced them with B-52Hs from inactivating squadrons at other former SAC bases. The 596th itself was inactivated when it was replaced by the 96th Bomb Squadron on 1 October 1993. The 20th Bomb Squadron was reassigned to the 2nd Wing on 17 December 1992 when it and its B-52Hs were reassigned to Barksdale from the 7th Wing, the latter which was relocating from the closing Carswell AFB, Texas and transferring to Dyess AFB, Texas in order to