Rocketdyne
The Rocketdyne Division was founded by North American Aviation (NAA) in 1955, and was later part of Rockwell International (1967-1996) and Boeing (1996-2005). In 2005, the Rocketdyne Division was sold to United Technologies Corporation, becoming Pratt & Whitney Rocketdyne as part of Pratt & Whitney. In 2013, Pratt & Whitney Rocketdyne was sold to GenCorp, which merged it with Aerojet to form Aerojet Rocketdyne.
Rocketdyne
Rocketdyne's next major development was its first all-new design, the S-3D, which had been developed in parallel to the V-2 derived A series. The S-3 was used on the Army's Jupiter missile design, essentially a development of the Redstone, and was later selected for the competitor Air Force Thor missile. An even larger design, the LR89/LR105, was used on the Atlas missile. The Thor had a short military career, but it was used as a satellite launcher through the 1950s and 60s in a number of different versions. One, "Thor Delta", became the baseline for the current Delta series of space launchers, although since the late 1960s the Delta has had almost nothing in common with the Thor. Although the original S-3 engine was used on some Delta versions, most use its updated RS-27 design, originally developed as a single engine to replace the three-engine cluster on the Atlas.