The Rocketdyne XRS-2200 was an experimental linear

aerospike engine The aerospike engine is a type of rocket engine that maintains its aerodynamic efficiency across a wide range of altitudes. It belongs to the class of altitude compensating nozzle engines. Aerospike engines have been studied for several years an ...

developed in the mid-1990s for the

Lockheed Martin X-33 The Lockheed Martin X-33 was a proposed uncrewed, sub-scale technology demonstrator suborbital spaceplane that was developed for a period in the 1990s. The X-33 was a technology demonstrator for the VentureStar orbital spaceplane, which was pla ...

program. The design was based on the J-2S, the upgraded version of the Apollo era J-2 engine developed in the 1960s. The XRS-2200 used the J-2's combustion cycle and propellant choice. Rocketdyne intended to develop the subscale XRS-2200 into the RS-2200 for use on the

VentureStar VentureStar was a single-stage-to-orbit reusable launch system proposed by Lockheed Martin and funded by the U.S. government. The goal was to replace the Space Shuttle by developing a re-usable spaceplane that could launch satellites into orbit a ...

. While the X-33 program was cancelled, two XRS-2200 engines were produced and tested.

References

{{Reflist Rocketdyne engines Rocketdyne Rocket engines