Delta is an American versatile family of expendable launch systems that has provided space launch capability in the United States since 1960. Japan also launched license-built derivatives from 1975 to 1992. More than 300 Delta rockets have been launched with a 95% success rate. Only the Delta IV Heavy rocket remains in use as of November 2020. Delta rockets are currently manufactured and launched by the United Launch Alliance.
The Thor-Able was an American expendable launch system and sounding rocket used for a series of re-entry vehicle tests and satellite launches between 1958 and 1960. It was a two-stage rocket, consisting of a Thor IRBM as a first stage and a Vanguard-derived Able second stage. On some flights, an Altair solid rocket motor was added as a third stage. It was a member of the Thor family and an early predecessor of the Delta.
The Delta G, or Thor-Delta G was an American expendable launch system used to launch two biological research satellites in 1966 and 1967. It was a member of the Delta family of rockets.
The Delta E, or Thor-Delta E was an American expendable launch system used for twenty-three orbital launches between 1965 and 1971. It was a member of the Delta family of rockets.
The H–I or H–1 was a Japanese liquid-fuelled carrier rocket, consisting of a licence-produced American first stage and set of booster rockets, and all-Japanese upper stages. The H in the name represented the use of liquid hydrogen fuel in the second stage. It was launched nine times between 1986 and 1992. It replaced the N-II, and was subsequently replaced by the H-II, which used the same upper stages with a Japanese first stage.
The N-II or N-2 was a derivative of the American Delta rocket, produced under licence in Japan. It replaced the N-I-rocket in Japanese use. It used a Thor-ELT first stage, a Delta-F second stage, nine Castor SRMs, and on most flights either a Star-37E or Burner-2 upper stage, identical to the US Delta 0100 series configurations. Eight were launched between 1981 and 1987, before it was replaced by the H-I, which featured Japanese-produced upper stages. All eight launches were successful.
The Thor-Delta, also known as Delta DM-19 or just Delta was an early American expendable launch system used for 12 orbital launches in the early 1960s. A derivative of the Thor-Able, it was a member of the Thor family of rockets, and the first member of the Delta family.
The Delta A, or Thor-Delta A was an American expendable launch system used to launch two Explorer spacecraft in October 1962. A derivative of the Thor-Delta, it was a member of the Delta family of launch vehicles. The Thor-Delta itself was a Thor booster with an Able second stage and Altair third stage.
The Delta B, or Thor-Delta B was an American expendable launch system used for nine orbital launches between 1962 and 1964. A derivative of the Thor-Delta, it was a member of the Delta family of rockets.
The Delta C, or Thor-Delta C was an American expendable launch system used for thirteen orbital launches between 1963 and 1969. It was a member of the Delta family of rockets.
The Delta D, Thrust Augmented Delta or Thor-Delta D was an American expendable launch system used to launch two communications satellites in 1964 and 1965. It was derived from the Delta C, and was a member of the Delta family of rockets.
The Delta L, Thor-Delta L, or Thrust-Augmented Long Tank Thor-Delta was a US expendable launch system used to launch the Pioneer E and TETR satellites in 1969 (failed) and HEOS satellite in 1972. It was a member of the Delta family of rockets.
The Delta M or Thor-Delta M was an American expendable launch system used for thirteen orbital launches between 1968 and 1971. It was a member of the Delta family of rockets.
The Delta N or Thor-Delta N was an American expendable launch system used for nine orbital launches between 1968 and 1972. It was a member of the Delta family of rockets, and the last Delta to be given an alphabetical designation - subsequent rockets were designated using a four digit numerical code.
The Delta 0100 series, also Delta 100, 0300 or 300 series, was an American expendable launch system which conducted orbital launches between 1968 and 1972. It was a member of the Delta family of rockets, and the first to be designated using a four digit numerical code. Two variants were flown, individually designated Delta 0300 and Delta 0900.
The Delta 1000 series was an American expendable launch system which was used to conduct eight orbital launches between 1972 and 1975. It was a member of the Delta family of rockets. Several variants existed, differentiated by a four digit numerical code. Delta 1000 was developed by McDonnell Douglas company in 1972.
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. Several variants existed, which were differentiated by a four digit numerical code. The Delta 1000, 2000 and 3000 series used surplus NASA Apollo program rockets engines for its first and second stages.
The Delta 4000 series was an American expendable launch system which was used to conduct two orbital launches in 1989 and 1990. It was a member of the Delta family of rockets. Although several variants were put forward, only the Delta 4925 was launched. The designations used a four digit numerical code to store information on the configuration of the rocket. It was built from a combination of spare parts left over from earlier Delta rockets, which were being retired, and parts from the Delta II 6000-series, which was just entering service.
The Delta 5000 series was an American expendable launch system which was used to conduct an orbital launch in 1989. It was a member of the Delta family of rockets. Although several variants were put forward, only the Delta 5920 was launched. The designation used a four digit numerical code to store information on the configuration of the rocket. It was built from a combination of spare parts left over from earlier Delta rockets, which were being retired, and parts from the Delta II 6000-series, which was just entering service.
