"Retired" . . . "1981-10-06Z"^^ . . "The Delta 2000 series was an American expendable launch system which was used to conduct forty-four orbital launches between 1974 and 1981. It was a member of the Delta family of rockets."@en . . "Delta 2000 series"@en . . "44"^^ . "1974-01-19Z"^^ . . "43"^^ .