Rocket Engines
Our rocket engines are built to customer specifications.  Below is a selection of engines that illustrate some of our capabilities.  Click on any engine class to learn more. (listed by order of thrust)

• XR-2P1 15 lbf N2O-Ethane
  R&D and educational, variable propellants and third fluid injections
   
• XR-3E17 56 lbf N2O-Ethane
  Stationkeeping - storable
   
• XR-3B4 50 lbf N2O-Isopropyl
  Stationkeeping - storable
  
  
• XR-3M9 50 lbf LOX-Methane
  Stationkeeping - storable
   
• XR-4A3 400 lbf LOX-Alcohol
  Auxilliary or primary propulsion
   
• XR-4K14 1,500 lbf LOX-Kerosene
  Primary propulsion, 'Rocket Racer' engine
   
• XR-4K5 1,800 lbf LOX-Kerosene
  Primary propulsion
   
• XR-5K18 2,700 lbf LOX-Kerosene
  Primary propulsion, Lynx
   
• XR-5M15 7,500 lbf LOX-Methane
  Primary propulsion, space storable

XR-4K5, 1,800 lbf LOX/kerosene Engine

In 2003, XCOR completed multiple successful test runs of the LOX/kerosene rocket engine, the XR-4K5. This engine is considerably more powerful than the previous isopropyl alcohol fueled rocket engine used in the EZ-Rocket. It produces 1,800 pounds of thrust (lbf), and runs at two and a half times the chamber pressure of the previous engine.

The XR-4K5 also uses a smaller and lighter electrical igniter design than previous generations.

This engine moved us closer to our goal of a reliable and economical vehicle for space tourism, as well as educational and commercial uses. The more powerful engine, and use of readily available and non-toxic fuels is a notable development in reliability and cost control of operating suborbital vehicles.