NASA wants one new 'brain' for two rocket engines (video)
Lee Roop | 
During a recent tour for Space Launch System Program managers, Mike Kynard, center, manager of the program's Engines element office, explains how test personnel use working parts from an RS-25 engine to test the new engine control unit at the Marshall Space Flight Center test facilities. (NASA/MSFC) HUNTSVILLE, Alabama -- How do you get a new heavy-lift rocket program off the ground with a "flat-line" development budget? One key for NASA is using a cache of 16 unused RS-25 Space Shuttle Main Engines (SSMEs) to help power the first few flights. But the space agency says they'll need new "brains" to do the job, and developing that upgrade is one of the jobs being handled by engineers and contractors at Marshall Space Flight Center, where the new rocket is being developed.NASA calls its new rocket the Space Launch System (SLS), a name that encompasses not only the booster but also the upper stage with the Orion crew capsule. The first version will be capable of lifting 70 metric tons of cargo to deep space, and the final version will lift as much as 130 tons. By comparison, the space shuttle could lift 24 metric tons into space, and the Apollo-era Saturn V, capable of supporting deep space flight, could lift 130 metric tons. Marshall engineers gave other SLS managers a tour of the developments in Huntsville so far on Oct. 17. (See video of the tour below)"The computer controlling the SSME was manufactured in the early '80s and many parts are now obsolete," Jeremy Richard, SLS Liquid Engines Office Subsystem manager, said in on Marshall's website. "While working on updating the technology, we discovered we could adapt the same controller being used by the new J-2X engine to the RS-25 engine, effectively streamlining the controller and resulting in a cost savings."An engine's controller regulates thrust and fuel mixture, and it passes commands and information back and forth between the engine and the rocket. It will take SLS engineers a year to tweak their design and test the controller at Marshall. After that lab approval, the controller will go to the Stennis Space Center in Mississippi for "hot-fire testing" in 2014. Engineers with Pratt & Whitney Rocketdyne, the company that built both the RS-25 and the J-2X engine that will power the upper stage of SLS, are working with Marshall on the new controller design."Our long-term objective is to use the same basic hardware design to control multiple engines," Richard said. "With a common physical design and just a few card change outs, we could control the RS-25, J-2X, and future engine designs at less than half the cost of a space shuttle main
engine controller." I cover NASA, space and biotechnology for The Huntsville Times and al.com. Follow me on Twitter @leeroop and email me at  Most Read