Aviation Week reports that NASA will delay development of the recently tested J-2X engine to keep within the budget provided by Congress.
Struggling to stay within a flat budget for the heavy-lift Space Launch System (SLS), NASA plans to halt development of the J-2X rocket engine that will power its upper stage after the ongoing development-test series.
Once the pacing item for the defunct Ares I crew launch vehicle, the Saturn-heritage J-2X may not fly until well into the 2020s. With the SLS program office expecting an annual development budget of $1.2 billion, near-term engine-development money is deemed better spent on a throwaway version of the RS-25D space shuttle main engine (SSME) that will power the SLS main stage. That engine—designated RS-25E—will use advanced manufacturing and design changes to lower the cost of the reusable SSME.
SLS critics have dubbed it the Senate Launch System because it seems intended to protect government pork in their districts rather than to develop a viable next-generation deep-space exploration vehicle.