Aerojet Rocketdyne is developing the country’s next great rocket engine, the AR1.  This engine incorporates the latest advances in propulsion technology, materials science and manufacturing techniques to be the lowest risk, lowest cost to the taxpayer, and fastest path to eliminating U.S. dependence on Russian-built rocket engines for national security space launches.

Incorporating the 500,000-pound thrust AR1 onto an existing launch vehicle is the fastest way to carry out this mandate. Rapid development of the AR1 will take place at space-qualified manufacturing and test facilities. Fueled by kerosene and liquid oxygen, the AR1 requires minimal changes to existing launch infrastructure and production facilities.  AR1’s choice of propellant combination, high-performance engine cycle, and thrust-level make it an attractive propulsion solution from the Delta-II-class through EELV with potentially applications for larger, reusable launch vehicles.


  • All-American design and production
  • Advanced oxygen-rich staged combustion kerosene technology
  • 500,000 lbf thrust (sea level)
  • Propellants: Liquid-oxygen (Lox)/Kerosene (RP-1)
  • Configured to accommodate multiple applications
  • Fast-paced and affordable development
  • Advanced low-cost manufacturing techniques

Our Role

Aerojet Rocketdyne is the industry leader in building liquid-propellant rocket engines and the only company in the United States that has ever developed and flown large booster engines, including the nation’s last three major liquid rocket engines: the RS-68, J-2X, and RS-25. The RS-25, based on the Space Shuttle main engine, is the world’s only reusable, staged combustion rocket engine.