http://www.spacenews.com/civil/1010-06-layoffs-nasa-slows-constellation-spending.html>>> NASA will complete an advanced manufacturing demonstration of the Ares J-2X upper-stage engine nozzle extension before the end of the year, at which point the project will be shelved, [Dale] Thomas [CxP Program Manager] said. In addition, NASA is expected to complete work on the A-3 engine test stand at Stennis Space Center in Mississippi, but the agency is not planning to spend Constellation funds to do it. “Constellation is just trying to save that test stand because we don’t need it to fire the engine unless we’re using that nozzle extension,” he said. “But Stennis is trying to find other funding sources to finish it up. It won’t get finished with Constellation funding.” <<<
Does this mean that the J-2X will be cancelled? Or is it just the nozzle extension that will be cancelled? If so, why is it being cancelled?
Quote from: yg1968 on 10/06/2010 07:55 pmDoes this mean that the J-2X will be cancelled? Or is it just the nozzle extension that will be cancelled? If so, why is it being cancelled?There is a CxP "ramp down" going on, if you noticed (has been in the news since last week). As can be seen from the article, "Spending on Constellation [] is expected to decline as much as 25 percent for the two months ahead".OK so how do you ramp down the development of an engine like J-2X ? Well... start by reducing the thrust and Isp... lol... stop working on the nozzle extension... lol... As a collateral damage, the A-3 test stand (vacuum testing) takes a hit... why test the engine in a vacuum if the nozzle extension is missing ?!P.S. The situation would be comical if one could ignore the absurdness
...opens the door WIDE OPEN for the RL-10 configurations....
I may be tempted to quote Sen.Shelby (R-AL.) if somewhat out of context ("This would not represent a step forward for innovation or for the future of our space program") but I won't .
Quote from: renclod on 10/06/2010 07:20 pmhttp://www.spacenews.com/civil/1010-06-layoffs-nasa-slows-constellation-spending.html>>> NASA will complete an advanced manufacturing demonstration of the Ares J-2X upper-stage engine nozzle extension before the end of the year, at which point the project will be shelved, [Dale] Thomas [CxP Program Manager] said. In addition, NASA is expected to complete work on the A-3 engine test stand at Stennis Space Center in Mississippi, but the agency is not planning to spend Constellation funds to do it. “Constellation is just trying to save that test stand because we don’t need it to fire the engine unless we’re using that nozzle extension,” he said. “But Stennis is trying to find other funding sources to finish it up. It won’t get finished with Constellation funding.” <<<Does this mean that the J-2X will be cancelled? Or is it just the nozzle extension that will be cancelled? If so, why is it being cancelled?
Most of the J-2X's requirements were due to it being the second stage engine of Ares I.Even the Saturn C8 only needed a standard 200klbs thrust J2 engine for it's upper stage.But I suspect the J-2X might eventually end up in SLS anyway.
I wonder if the engine or at least parts of it could be reused on some RLV type project it seems a shame to waste it.Some early shuttle concepts did call for using a J2 engine.
Quote from: Patchouli on 10/25/2010 02:39 amI wonder if the engine or at least parts of it could be reused on some RLV type project it seems a shame to waste it.Some early shuttle concepts did call for using a J2 engine.After spending some time looking at "all-liquid" heavy-lift concepts, it seems clear that the trade when it comes to SLS is five segment booster versus J-2X. If NASA uses five segment booster, it won't need J-2X any time soon, if ever. If NASA were to go with an all-liquid heavy lifter (very unlikely, but fun to contemplate as we have been doing in the "all-liquid SD" thread), it would need J-2X or something similar. (Conversely, if NASA cancels J-2X, it will be stuck with five segment booster for the foreseeable future). - Ed Kyle
In all honesty Ed, with the rise of commercial spaceflight and the fact that we have rl 10, what is the justification for needing j2x? Even for beo heavy missions it seems an rl10 stage outpreforms j2x, and if it does not raptor and other commercial engines could replace rl 10 in future.what is the justification for this?
Quote from: FinalFrontier on 10/26/2010 12:30 amIn all honesty Ed, with the rise of commercial spaceflight and the fact that we have rl 10, what is the justification for needing j2x? Even for beo heavy missions it seems an rl10 stage outpreforms j2x, and if it does not raptor and other commercial engines could replace rl 10 in future.what is the justification for this? As I said, not having a high thrust upper stage engine necessitates use of the big solids for decades more, for as long as SLS flies. Low thrust upper stage engines only work on a super heavy if they are confined to the latter, mostly horizontal exoatmospheric portion of the ascent to orbit. That means that they can't work as second stage engines on an all-liquid two stage super heavy. - Ed Kyle
NASA's J-2X is an efficient and versatile rocket engine, offering the ideal thrust and performance characteristics to power the upper stage of a heavy-lift launch vehicle. Hardware for the first engine is being assembled at Pratt & Whitney Rocketdyne and at numerous subcontractor locations across the country, with testing anticipated at NASA's Stennis Space Center in early 2011. ...Page Last Updated: October 30, 2010
