Sinking in the quicksand of HPR
- Jul 31, 2018
- Reaction score
- Pittsburgh, PA
Yep.MCF -- Major Component Failure on engine 4.
A few points:To do one Artemis mission, three totally different launch vehicles need to place three totally different spacecraft in orbit around the moon (and the lander has to dock automatically with the Lunar Gateway). Apollo only needed one rocket, the Saturn-V to do that.
It just boggles my mind that we flew rs25s from '81 to '11 but can't sustain a full test, to say nothing of the MIA Integrated Powerhead Demonstrator.
Meanwhile Elon is over here doing full flow gas-gas staged combustion and cranking up the pressure both physically and metaphorically.
I guess too much pork really is bad for your health.
From what Ive heard around town, it wasn't an engine problem, but a nearby (important) component
Also from the Ars Technica article, it appears that there were three significant issues that need to be addressed:NASA is leaning towards repeating the test. That might take another 3 or 4 weeks.
That might be related to one of the differences between Shuttle and SLS. On the Shuttle, the APUs, that provide power for the TVC system, are driven by Hydrazine, because the same APUs are also required for landing. On SLS, the APUs are driven by hot hydrogen gas from the engine.
This quote sums up the entire program pretty well IMO - astounding how NASA has lost its way since the glory days of Apollo/Saturn. SpaceX (and others) do it way more affordably and without the endless delays."SLS needs to fail just enough to maintain a credible promise to keep getting funded. It's primary purpose is to keep ex shuttle rocket infrastructure employed, not to provide a competitive launch system."
"All of the SLS related documents have flight heritage. They got it being slung across the room in frustration by the engineers at one point or another."
"The failed Soviet N1 has more flight time than SLS at this time."
Basically, because NASA presently doesn't have a plan to reuse any of its rocketry equipment. At least, that is not part of the SLS architecture.I definitely can't figure out why they throw their RS-25 motors away. Such a waste. I guess it is just so they mitigate risk and development time (that hasn't worked!). They were engineered to have a life expectancy of 27000 seconds (that's 7.5 hours of runtime).
Wasn't the whole original idea of SLS to be a reusable rocket, or mostly like the Falcon 9?Basically, because NASA presently doesn't have a plan to reuse any of its rocketry equipment. At least, that is not part of the SLS architecture.
The fact that RS25's could be reused is of little value, since there is not feasibly way to take advantage of that capability.
The fact that RS25's were used at all, was probably a mistake, but I am not certain, since the data on cost of a new engine design vs. repurposing RS25's is not publicly available. NASA had them sitting in a warehouse, and people got nostalgic and couldn't simply write them off. Instead, they got fixated on using 4 semi-under-powered RS25's (for the task at hand), and augmented them SRBs.
Oh well, if nothing else, NASA has been paying to preserve the R&D and manufacturing capability to build big rockets. Whether they fly or not, is secondary.
SpaceX's BFR seams to be gaining credibility with each test. It not looks increasingly likely that BFR will be lunar flight ready before SLS.