sentences:  The 549th Air Base has seen many redesignations since being activated in 1942 as the 6th independent Transport Aviation Unit.The unit has been based at Levashevo since 1960.Aircraft in service have included the Mi-1, Mi-2, Mi-4, Mi-6 (Mi-6VPK and Mi-22 in the 1980s), Mi-8, Li-2, Il-14, An-2, An-14, An-12, An-24/26, Tu-124, Tu-134, 1981-, and the Il-22 from 1981.