Boldly going where Elon Musk will probably go before: NASA successfully tests SLS Moon rocket core stage NASA’s Space Launch System (SLS) core stage has finally completed its test, taking the Artemis program one step closer to the Moon and relieving nervous engineers across Stennis Space Center and beyond. The second hot-fire test of NASA's largest ever rocket element went off without a hitch for 8 minutes and 19 seconds after …
The rocket caught fire, and I don't mean the flames being deliberately shot out of the nozzles. It didn't cause any problems and was passed off as only happening because the rocket stayed where there's plenty of air to allow it to burn. However I can't help think they'll have to replace the burnt bits and that'll add more delays.
>the bits that burned were cork insulation and of little consequence.
Not to the cork farmers whose congressional district vote secured this project's future
Nasa's real challenge is to make the coal fired 2nd stage work, otherwise the representative from Pennsylvania will vote against it
Nasa's real challenge is to make the coal fired 2nd stage work
I can't quite work out how deep that joke it. For the benefit of those who don't know both the first and second stages use hydrogen for their propellant and oxygen for the the oxidiser. The main source of hydrogen is from steam reforming of natural gas ...... but some is make from coal. Most oxygen supplies come from the cryogenic distillation of air. This normally uses electricity and in the US 30% of electrical power from from coal so the Pennsylvania representative should be voting for it.
I'm guessing that the fire that was seen around the tops of the engines was of no consequence?
There was some discussion of extra materials having been added to protect the underside of the rocket for what was an artificial test environment (no air flow and no reduction in available oxygen as the rocket didn't climb), and the adhesive used to hold them in place melted and burned.
SLS has cost $20 billion so far, and will be more before it manages a single launch. While I don't know the exact split of cost on various parts, it feels we must be at least a couple of orders of magnitude beyond "multi-million" being the best descriptor.
"330,000 gallons (1.249 million litres) of water per minute"
That's a smidge under half an Olympic-sized swimming pool per minute. (0.4991)
I don't know why we don't have a proper unit of time to demonstrate the flow rate. Minutes are so passé. The best I can do right now is 10.062 Olympic-sized swimming pools per milli-fortnight.
You omitted the 10000 kg of sugar (or suitably cancer inducing alternative) and approx 10000 lt of "colorings" from the recipe. Not that I have opinions about the drinks they serve in Texas - no Sir - not me.
Oh - and enough ice to clear the Weddell sea - what? they already did?
>Not that I have opinions about the drinks they serve in Texas - no Sir - not me.
Have you considered that this is just Texas' attempt to make oil a renewable resource?
With dinosaurs now sadly extinct we need a new specious of extremely large land animals (with brains the size of walnuts) to die and their bodies by converted into fossil fuel.
"Well, it's only going to take a month or so to refurbish them for a flight. Not so sure about the refurbishment time after they get used on the flight though. That may be a tad longer. Unlike SpaceX :-)"
There are no plans to recover and refurbish the engines after they are used on a flight. It takes too much capability to land a first stage for reuse. It's a big hit to carry the landing gear and the fuel. Even SpaceX has to splash a few when the payload is over a certain weight or the orbit of the payload is too high. It's far less expensive for NASA to build new rockets than to short the payload on each flight to allow for landing.
Recovering the first stage of a rocket hasn't been a technological problem for decades. It's been a financial gamble. If parts are beefed up to be used over and over, they get heavier. Mass is everything on a rocket. The more mass the vehicle, the less payload it can carry and the lower the altitude it can achieve. John Carmack (Doom/Quake) was landing rockets with his company, Armadillo Aerospace, long before Elon "came up with the idea". And, that was after NASA was landing rockets on the moon in the 60's and working on other applications with the Delta Clipper.
Masten Space Systems and Armadillo Aerospace won the NASA Centennial prizes in the Northrup Grumman Lunar Lander Challenge (2009). Yes, the rockets didn't go into orbit, but neither does the first stage of the Falcon 9. It's not about the height, it's about the control it takes to land at all. Blue Origin is making great strides. Their sub-orbital rocket has flown many times perfectly from their site in Texas. BO tends to keep things quiet and the NDA that employees have to sign is very draconian. Since they have lots of money in the form of Jeff Bezos, they can afford to take things one step at a time and do it right. The hare will beat the elephant to the finish line, but the elephant will be carrying far more cargo. If the goal was to put some mice on the moon, maybe SpaceX would win the race, but the goal will be to put a colony on the moon with the ability to transport people in both directions.
It's tempting to rubbish the SLS because, well, SpaceX.
Overhyped and over there--->
It's been interesting to see the different approaches between SLS and SpaceX/Starship. Next step for SLS is Artemis, and a possible trip around the moon come November. Individual elements have been tested, so now it's sticking it all together and sending it into the wild blue yonder.
For Starlink, it's been 10 launches, 10 landings, 1 landing you could walk away from, if you were really quick. Assuming SpaceX can nail the landings, it's still got to integrate it's second stage. And re-design the second stage, ie Starship to be human rated, or just carry any useful payload. So Space-X seems a long way off by comparison.
So one is commercial outfit moving fast and breaking things to make launches cheap.
The other is a dead end project to re-use a small stock of 30year old engines, and then build some expensive copies. In a dead end project to go to the moon quickly to:
demonstrate our technical superiority over N Korea
distract attention from the presidential scandal of the day
funnel funding to a bunch of aerospace companies that are losing money *(delete as applicable)
"So one is commercial outfit moving fast and breaking things to make launches cheap."
The cost per kilo with SpaceX isn't dramatically cheaper. At least they don't charge the government any less if it is. Being a private company, their books are available to look at, but it's telling that they have $500mn funding rounds a few times a year. You'd expect that they could self-fund if they were doing as well as some fans believe.
distract attention from the presidential scandal of the day
Would that be Solyndra? But SLS was incepted in 2011, so during Obama's reign.
funnel funding to a bunch of aerospace companies that are losing money *(delete as applicable)
Of which SpaceX is just the latest in a long line. It's had it's own large share of funding funneled in it's direction.
Whilst you are correct I think you are somewhat misrepresenting the situation. SLS is a throwaway - in the best pork barrel traditions of the US Gov. The Artemis 1 mission could fly on Falcon Heavy and you'd still have the boosters.
Starship (both the 'capsule' and the booster) are early representatives of the next generation - SLS is just another iteration of the same tired old system. So for the record it's Starship 1 out of 10 'successful' landings vs Boeing 0 out of 0. Hey - at least they are consistent, Also - SpaceX do seem to already have a 7 seater human rated capsule that has flown 2 more missions than Orion - so if you are comparing like with like that would be a closer one.
For the record - while I think Boeing/ULA are little more than a highly efficient leach on the public purse and long ago stopped innovating - I really really want the Artemis program to work and be a spectacular success. It's a popular conception that NASA were once a freewheeling outfit that degenerated into a bureaucracy - but if you read the accounts of the early days it was always thus. They were just given political ego generated unlimited budgets. They still managed some of the most stupendous achievements in history despite the paper pushers and I sincerely hope they continue to do so.
That's the really sad thing about the SLS.
Assuming it is ever launched, and works and gets to the moon - then what?
It was designed as a quick/cheap/politically-expedient way to use some old technology for a showboating trip.
It's like Britain demonstrating a post-Brexit challenge to Airbus by taking a Concorde out of a museum and refurbishing it for a single flight.
Someone who I trust on this one told me that when Concorde went out of service, BA quickly scuppered their fleet (drained hydraulic oil etc.) to stop Branson buying them, refitting them to pass modern flight safety rules and getting them back in the sky under the Virgin flag. BA weren't prepared to lose that publicity war.
"The Artemis 1 mission could fly on Falcon Heavy and you'd still have the boosters."
Not really. You'd have to discount the mass of available payload capacity by the mass of the landing gear, extra fuel and added margin for a reusable rocket. With a rocket you plan to drop in the drink, you can optimize for the maximum amount of payload. That can often be much cheaper.
"For Starlink, it's been 10 launches, 10 landings, 1 landing you could walk away from, if you were really quick. "
Very true, but it's currently 0 launches for SLS. Let's check back in 6-9 months to see where both programs are. I suspect SpaceX will have both stuck a landing and done a two stage launch (maybe even a successful stage landing) by then. SLS I suspect will have a firm commitment to the color of the launch procedures manual for Artemis. Then let's check back again in early 2023.
Don't get me wrong, I'd love to see Artemis succeed, and I agree there's an abundance of hype around all of Musk's endeavors. I just think that when you consider the pace of development, SpaceX has the current edge. SLS will beat SpaceX to the moon, but in terms of having a commercially viable heavy lift launch platform, I'd bet on SpaceX coming out ahead im the end.
I also agree that it's fascinating to see the different approaches to system development. I just hope there are strong firewalls between the processes on SpaceX development side and the human rated flight side.
>I also agree that it's fascinating to see the different approaches to system development. I just hope there are strong firewalls between the processes on SpaceX development side and the human rated flight side.
One is test things quickly / discover problems / change things.
The other is take so long building and testing everything that it is no longer possible to change anything fundamental (o'rings, foam insulation) because that would make you even later - so launch and hope.
How good would your software be if your only requirement was that no unit test could ever fail? How reliable would it be in production when faced with unknown new problems?
"One is test things quickly / discover problems / change things."
The downside of that approach is to fail because it turns out that a particular relief valve design is prone to freezing open when it's humid or a system needs redundant sets of one-way valves to prevent back flow of hypergolic fuels. Just to name two very basic problems that SpaceX has discovered that have led to massive explosions/crashes. You don't want a bad choice in valve selection cost a couple of hundred million. You want it to cost 10k in time and testing.
Engineers "breadboard" a rig to make sure that an assumption they didn't realize they were making doesn't turn around and take a big chuck out of their backside.
The 0-rings could have been changed on the boosters of the Space Shuttle. So could the foam. Both were. The O-ring issue was already a known problem that never was addressed and nobody thought that low-density, light-weight foam could damage the leading edge of the wing. There was no "safety margin" when the O-rings burned at all nor when foam came off of the main tank. Neither was supposed to happen at all.
I'm guessing you mean Starship rather than Starlink. However, I'm not sure where you get 10 launches from. Only SN8, SN9 and SN10 where really Starship; many of the others never flew (unless you count SN4 "flying" when it failed under pressure testing!) as they were engineering prototypes used to validate the construction process. SN5 and SN6 (I think it was) made a couple of "hops" across the pad, but these weren't really flights (but they did land ok).
The next ones to fly are SN11 and SN15 - SN12, 13 and 14 were never completed as the data required was obtained from earlier tests.
> Assuming SpaceX can nail the landings, it's still got to integrate it's second stage. And re-design the second stage, ie Starship to be human rated, or just carry any useful payload
That *IS* the second stage, and it *IS* going to be human rated. There is a very large payload section at the top. They have not even started on the booster.
That *IS* the second stage, and it *IS* going to be human rated. There is a very large payload section at the top. They have not even started on the booster.
I know, but the second stage still needs to be integrated with the booster, which is waiting in the wings. Sure, there may be a lot of space in the top, eg-
As envisioned in the 2017 design unveiling, the Starship is to have a pressurized volume of approximately 825 m3 (29,100 cu ft), which could be configured for up to 40 cabins, large common areas, central storage, a galley, and a solar flare shelter for Mars missions.
Which is typical Musk-style 'artists impressions'. A bit like the Hypeloop, which went from maglev to air-cushion (in a near vacuum) to Model 3's being chauffer driven along a sewer pipe. But basically much work to do before SpaceX can put people on the moon.
But again I think it's a difference in development philosophy. SpaceX has been unfraid to fail, and been keeping up a high tempo of SN-X tests. Later this year, we might get to see if SLS/Artemis makes it around the moon and back. But they seem further ahead by some margin. Starship doesn't have a crew capsule, life support systems, crew escape system, or even a hatch and a rope ladder. Or as a 'Super Heavy' launch vehicle, any kind of payload bay & fairing.
But that might be a difference in mission philosophy. SpaceX will almost certainly lose the Moon race, but has some interesting ideas about Mars. So might be content to work on tanker Starships first, and crewed versions once in-orbit refuelling works and a Mars (or Moon) lander can be launched.
Interesting times though, and curious if SpaceX will continue with a re-usable Starship in it's current form.. Or if it's winglets will grow and it turns into a glider. NASA presumably did a lot of the heavy lifting before coming to the conclusion that a space plane might be better.
Not to worry. They'll go back to committee to tentatively decide whether there's a fragment of possibility that something untoward might happen and make NASA look bad. It'll be in committee for six or so years before they decide to revise the scope of the plan, give another $20 billion for development. Musk will have grandkids on Mars before NASA moves. Sad isn't it.
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