The Moon or bust, says NASA, after successful SLS/Orion test flight NASA is ready to fly a crew of astronauts to the Moon next year after the success of the first test flight of its Space Launch System (SLS) rocket and Orion capsule. After months of delay due to technical issues and bad weather, the SLS, with the Orion spacecraft onboard, finally took off from the Kennedy Space Center in …
Yes, actually. Circuit breakers just pop like that, even on light aircraft. And the heatshield is fine, it just acted slightly differently than the models predicted, which only goes to show those models were wrong and need improving, not that the heatshield has a problem.
" the Artemis II mission, which will fly a more powerful version of the SLS rocket – and carry a group of astronauts inside Orion."
Surely if astronaut safety is a priority they would fly the modified / more powerful version without occupants first and only fly astronauts on the same stack that has been tested? While to a large extent the components are the same, and the new component will have had it's unit tests, changing any component basically invalidates the previous testing with respect to whether the new component will 'play nice' with the rest of the previously-tested stack. That's what 'integration' or 'system' testing is for.
I wouldn't dream of putting any software into Prod that was a modified version of what's been passed in testing.
Since SLS is currently utterly reliant on SpaceX's Starship to actually get to the moon (rather than just near it)...
I would actually pick the dragon, it's a well proven ship to get to orbit - and if I recall correctly the heatshield was originally designed to cope with lunar reentry. SpaceX agree: "The Dragon spacecraft is capable of carrying up to 7 passengers to and from Earth orbit, and beyond" That 'and beyond' is important.
Of course the current heatshield might not (mass being expensive and all), but it's a relatively small change to a well known system.
I think they only have enough of certain hardware (including main engines I believe?) for a fixed number of flights, regardless of whether they are tests or real/crewed.
So there is a lot of pressure for the tests to all pass and to not downgrade a planned crewed mission to un-crewed test.
Opinions may vary on whether this is a good thing or not....
It was one of the proposals... but I'm sure there would have been enough proposals put forward to come up with a workable plan if they had wanted to.
Those engines are marvels of engineering, it really does seem to be a shame in today's world to simply ditch them.
I appreciate that reuse wasn't seriously an option in 2011, but we're a little way on from that now, and to be throwing away engines that you've forgotten how to build is so badly self limiting.
They didn't forget how to build the RS-25 engines, they only shut down production in 2007/8. Instead they're building a new, cheaper*, non-reusable version (RS-25E).
* They claim it will be cheaper, but I'm sure this is a cost-plus contract so we can guess how that will turn out.
Go read some history on Apollo-Saturn. The first crewed Apollo mission went all the way to the moon, it didn't screw around in earth orbit tests.
Then read up on the Space Transportation System's history. NASA treated that as a continual development project. And it bit us in the ass, twice.
Riding a rocket in to space is not a safe activity. Testing, modeling, forecasting, predicting. But eventually someone climbs aboard and takes the risk. Godspeed, good luck, and if I ever had the opportunity to take that same risk I would do it in a heartbeat.
A beverage to the men & women who have the guts to do it.
So they indeed blew the bloody doors off while upgoing - nice
Is the heatshield a worry downcoming? Well, "less than expected" can still mean "more than required" The heatshield is still trusty AVCOAT, but the ablative structure's new manufacturing, and assembly process had been modified.
Modifications from known data, means it's one of those 'known, unknown' thingies..They know AVCOAT works, and they know how well it worked in a past configuration (Apollo) The new configuration and process is (was) unknown - they had no data for it, and was therefore (gulp) modelled.
The data returned did not match the model.
What did they do differently? Different bonding, and production line modular manufacture - the Apollo era heatshield was handcrafted and bonded, in a time consuming process. The new configuration worked though, so there is that going for it,
What else? Well, before we decry the modelling for the heatshield performance, we should mention the novel, modelled 'skip entry' - that worked great. It was intended to reduce the stresses of downcoming, including heat stress; so I'm wondering if the "less than expected" relates more to the modelling of reduced heat, and stress with a skip-entry, than to the performance of the ablative heatshield.
The Artrmis mission remember, was coming in hot - damn, hot, real hot! Hotter than a hot thing on planet Hot. Beyond known heat stress data is what I'm getting at.
So, despite the discrepancies in modelled data, and expected performance, both the skip-entry and ablative shield was well done - no astronauts would have been well done, or skited into the black and well gone.
Still an horrrendous waste of money,
"The Artrmis mission remember, was coming in hot - damn, hot, real hot! Hotter than a hot thing on planet Hot. Beyond known heat stress data is what I'm getting at."
Well, entry velocity was 24,581 mph for Artemis 1 vs 24,816 mph for Apollo 10 - that means Apollo had ~2% more energy to deal with per unit mass.
Artemis is only ~10% more massive ~20t -> ~22.5t (i.e. 10% more energy)
Apollo was only 80% the diameter (4m vs 5m), so presumably loads on the heat shield would be 50% more? (not run the physics on this one)
Basically it's within reasonable bounds of heat loads we dealt with 50 years ago.
"the novel, modelled 'skip entry' "
Novel only insofar as its the first time it's been used (for this definition of a skip reentry - i.e. leaving the atmosphere to perform the skip) on a human-rated reentry vehicle - the Apollo CM used a "skip whilst remaining within the atmosphere" variant, and non-crewed RVs have previously used this "exit the atmosphere" variant as well.
"They will build an emergency egress system at the launchpad in case the crew needs to make a last-minute exit from the rocket."
Ummm...wot?!?!?
Hasn't this been standard practice, on and off, since the Apollo era?
Maybe it's just worded badly and the "emergency egress system" just hasn't been built yet because there's been no need for unmanned launches. Why build a one use system that might need maintenance when an actual human crewed launch is happening. At least I hope that is what is meant and this is not a case of "oooohhh, maybe we should put this in" at the last minute.
Apart from flag wavers, who actually cares?
Flying craft into asteroids, dive bombing into distant planets or visiting far of bodies I totally get, but nan on the moon?
In the 70s people got fed up with the costs and it became a non-event.
So my question, why? So we can get to Mars? Why? We have robotic craft that weren't available back in the 60s and 70s.
Grumpy old me just see's it a another expensive willy waving contest, just this time with China and India.
Guess it may be time for a cover of "Whitey On The Moon"
> Why?
Because baby steps. Because until very recently we weren't even able to go (back) to our moon (anymore).
Obviously one can chose to totally disregard one's own limitations and fantasize about going to Mars and beyond, but more reasonable/prudent people would like to make sure we can at least send people as far as our own satellite before trying Mars.
I care, and I'm not even a US citizen. I wouldn't make assumptions on other people's motivations. If I posted something on the lines of "apart from ignorants devoid of curiosity, who actually disapproves this?", you would be rightfully pissed, and no amount of "Genuine Question" tags would fix it. Genuine questions do not have precompiled answers.
Anyway, sending men on the Moon probably doesn't let us do more exploration than robots, but it does let us learn more about how to live there. That's the kind of thing that could well have payoffs, even if you don't know in advance what they would be. Science is frequently in that situation. There was a time when electricity was considered a useless toy. I could easily see advances in biology, materials science, medicine and more coming from this, that you wouldn't have with robots alone.
Yeah, it's expensive, but we spend way more money than that on wars, fossil fuel subsidies, advertising and movie remakes. At least with space exploration we're advancing knowledge, even if it's not immediately useful, as opposed to doing things that are actively harmful.
There are dozens of things public money is spent on, that I would invest elsewhere. If I actually took the time to go look, I'd probably find hundreds.
And yet, I do not feel the need to go visit movie boards to declare that public funding for movies made for profit should be canceled. Because I respect the fact that my own priorities are not universal values.
So we are considering really going to the moon this time, cool.
Now I have to wonder if this is about mining H3. Years ago after watching the comedy Iron Sky, I thought H3 was made up, found out last year it is real, and Russia, India, China and the US all have had drafts to mine it on the moon since the '90's. Crazy stuff to learn is real, and I thought I was up on tech,,,.
So the rockets delivered more thrust than intended and panels cracked.
Funny how nobody is mentioning G force.
I can't help wondering whether an obscure but ingenious little gadget known as a throttle could have saved those panels, at the expense of taking a little longer for the ride and hence burning up the magic saving in fuel.
Not sure I'd be happy to ride an "improved" one of these without another unmanned test first. There are heroes and there are the foolhardy.
So the rockets delivered more thrust than intended and panels cracked.
Funny how nobody is mentioning G force.
The broken panels weren't in the spacecraft or rocket. They were in the "mobile launcher". I suspect the issue is not the amount of thrust generated by the rockets, but the amount of noise and vibration to which the stuff around the launch pad is subjected.
SLS is the absolute embodyment of a government program. It took decades to build an obsolete rocket with tech that was out of date when the program was started, then it wasted money for a few decades and now the only reason why it keeps going is government momentum.
Meanwhile the private sector (SpaceX) has eclipsed them in every way except for government compliance shenanigans.
It is exceedingly rare that any business launches, literally or figuratively, a truly challenging and original product or service from whole cloth. Innovation is often, nearly always, funded by governments because initial costs versus likely rewards are wildly out of scale - from ships of war and commerce to microwave ovens to rockets and computers and, eventually, space travel. Oh, and this Internet thing.
The pseudo-mythical man with a plan in a van just can't cover the startup price of truly difficult things - or the costly failures that come with iterative development.
Sometimes, even frequently, those government-funded technologies and opportunities that work and can scale are then trickled down to business though public/private partnerships because repetitive manufacture and refinement at scale, however relative, is cost-manageable and potentially profitable. And governments get back some or all of their investment over longer time-scales through licensing and taxes and demand usage (i.e., "...we need you to put this special satellite in orbit but not mention it on the cargo manifest...").
SpaceX is one of numerous beneficiaries of that managed government largesse, and it's worth noting that their innovations are minor improvements, mostly cost related, to driving a low Earth orbit bus route. That doesn't make them bad or inferior or useless, it underscores that the system is working according to plan.
Agree with a lot of the comments. This reminds me of the Space Shuttle thinking that led to the loss of two shuttles.
And this is at the very beginning of the flight testing. It does not bode well for the future. This thinking was evident in the lead up to the initial launch. Lost of exceptions being made when super-cautious maybe would have been more effective.
Only if the issues reported are well understood and easily correctable should they move on. There is so much pressure to fly because of the money spent to date.
The Register 
Biting the hand that feeds IT
Copyright. All rights reserved © 1998–2024
