SS Altair is an Algol class vehicle cargo ship that is currently maintained by the United States Maritime Administration as part of the Military Sealift Command's Ready Reserve Force (RRF). She was built as a high speed container ship by Rheinstahl Nordseewerke in Emden, West Germany, hull no. 431, for Sea-Land Service, Inc. and named SS Sea-Land Finance, USCG ON 550722, IMO 7315571. Due to her high operating cost, she was sold to the United States Navy on 5 January 1982 as USNS Altair (T-AK-291).

The Algol-class vehicle cargo ships, also known as Fast Sealift Ships (FSS) or SL-7s, are currently the fastest conventional steam powered cargo ships in the world that are still (intermittently) operating, capable of speeds in excess of 33 knots (61 km/h).. Although in reality both are laid up due to their high operating costs and less than green credentials in terms of fuel burned in transporting one unit of cargo per nautical miles traveled. Originally built in 1972 and 1973 as high-speed container ships known as SL-7s for SeaLand, the ships' high operating costs limited their profitability. All eight ships were acquired by the United States Navy in 1981 and 1982, with the last ship converted, delivered to and placed in service with Military Sealift Command in 1986. The conversion entailed the installation of four cranes, addition of roll on/roll off capability and a redesign of the cargo hold to better facilitate storage of vehicles. Due largely to their high cost of operation, all fast sealift ships are kept in Reduced Operating Status, but can be activated and ready to sail in 96 hours. All ships are named after bright stars in the night sky.