Space Shuttle (1981-2011). Key rocket engine technologies were advanced at the Rocketdyne Canoga plant: gimbaling of rocket engines, introduction of engine injector baffling plates for improved combustion stability, tubular regenerative cooling, "stage and a half" engine configuration first used on Atlas, thrust chamber ignition using pyrophoric chemicals and electrically-controlled starting sequences. Aerojet Rocketdyne moved their office and manufacturing operations to the DeSoto campus in 2014. Demolition and site clearing of the former Rocketdyne facility in Canoga Park commenced in August 2016. As of February 2019, the future land use of the site has not been announced. McGregor, Texas Rocketdyne's Solid Propulsion Operations business unit was engaged in the development, testing and production of solid rocket engines at McGregor, Texas for nearly twenty years. The Rocket Fuels Division of Phillips Petroleum Company began using the former Bluebonnet Ordnance Plant in 1952. In 1958, Phillips and Rocketdyne entered a partnership to form Astrodyne Incorporated. In 1959, Rocketdyne purchased full ownership of the company and renamed it Solid Propulsion Operations (later designated the Solid Rocket Division). The purchase caused Rocketdyne to invest in facilities and research at McGregor towards diversification into other propellant types and rockets engines. Notably, Rocketdyne installed a facility capable of testing engines having up to three million pounds of thrust. The Solid Propulsion Operations initially used ammonium nitrate -based propellants in the manufacture of gas generators used to start aircraft jet engines, turbo pumps of the Rocketdyne H-1 rocket engine and the manufacture of the Jet Assisted Take Off (JATO) rocket engines. Ullage motors were developed for the Saturn V Space Vehicle. The group also built solid propellant boosters providing for the zero-length launching of North American F-100 Super Sabre and Lockheed F-104 Starfighter aircraft. The motor provided a takeoff thrust of 130,000 lbf for 4 seconds, accelerating the aircraft to 275 miles per hour and 4 g before separating and dropping away from the jet. In 1959, the group began using ammonium perchlorate oxidizer combined with carboxyl-terminated polybutadiene (CTPB) binder to produce solid propellants marketed under the trade name "Flexadyne." For the next nineteen years, Rocketdyne used the formulation in the production of solid rocket motors for three major missile systems: the AIM-7 Sparrow III, AGM-45 Shrike, and the AIM-54 Phoenix. Rocketdyne transferred operation of the McGregor plant to Hercules Inc. in 1978. A portion of the former Bluebonnet Ordnance Plant is now used by SpaceX as their