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NASA Delays First Flight of New SLS Rocket Until 2019 (arstechnica.com)
schwit1 writes: Despite spending almost $19 billion and more than thirteen years of development, NASA today admitted that it will have to delay the first test flight of the SLS rocket from late 2018 to sometime in 2019. "We agree with the GAO that maintaining a November 2018 launch readiness date is not in the best interest of the program, and we are in the process of establishing a new target in 2019," wrote William Gerstenmaier, chief of NASA's human spaceflight program. "Caution should be used in referencing the report on the specific technical issues, but the overall conclusions are valid." The competition between the big government SLS/Orion program and private commercial space is downright embarrassing to the government. While SLS continues to be delayed, even after more than a decade of work and billions of wasted dollars, SpaceX is gearing up for the first flight of Falcon Heavy this year. And they will be doing it despite the fact that Congress took money from the commercial private space effort, delaying its progress, in order to throw more money at SLS/Orion.
SLS has always been a make-work program to preserve legacy jobs at Space Shuttle contractors. If NASA (or anyone else) has set out to design the best possible heavy-lifter with today's technology, they wouldn't use strap-on SRBs, and probably wouldn't bother with H2/LOX in the first stage either. (Just look at the two private companies that are developing heavies -- SpaceX and Blue Origin.)
I have a running bet with some friends on how many times the SLS will fly (if ever). My money's on two flights before it gets the axe.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
It's not worth rushing it
SpaceX is notorious for delays.
The big and crucial difference between the two organizations is that SpaceX has been incrementing up to FH while simultaneously doing something commercially useful, as opposed to NASA's One Big Project approach (which it had to do for a variety of reasons.
"I don't know, therefore Aliens" Wafflebox1
Out of curiosity, which era of history or presidential legacy are you comparing those 8 years to? I'm kinda old and I don't recall any president in my lifetime not fucking up the economy. Clinton balanced the budget, but left GWB with a huge cleanup bill which Clinton should have been spending money on the whole time, Reagan, Bush and Bush all spent money like a whore who found a rich customer's credit card on the floor after he left.
You seem to think the grass used to be greener... it was always brown and we were convinced by our leaders it just needs more water. The only real difference is Obama was Internet era and we saw what he was doing. Before that it was much easier to keep you from seeing the yard.
SRBs are a pain-in-the-ass to "refuel"... it takes weeks of meticulous work. Liquid H2 is a "pernicious molecule" according to Elon Musk. It's so tiny it's hard to contain; it's colorless and odorless, and burns with an invisible flame. Yes, it gives you a higher ISP than RP-1, but not so much higher as to make it worth the trouble. (H2 is mostly used in upper-stages, where the higher performance has a better pay-off.)
Note: IANA rocket scientist, the above is just what I've gathered over the years as an armchair space enthusiast.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
Solids have horrible failure modes for a manned space flight platform. Not to mention they are inefficient like heck. The only reason to use solids is because you're indirectly funding ICBM tech. I'm not sure I agree with the LOX/H2 thing though. It kind of depends on the vehicle and engine design. But it is true hydrocarbons are a lot more dense and hence result in less vehicle manufacturing costs.
True. I hadn't thought of that. But I'd note that Ariane-5 was developed in the mid-90s, and was based on the Ariane-4, which also had SRBs. I wonder if they would make the same design choices today?
Perhaps not but sometimes the best path forward is to not try to relive the past. Perfect can be the enemy of good. Something can be very useful without being optimal. The computer you are typing this on has a lot of historical cruft in it but removing that cruft is generally more expensive than simply building around it. If it is economically not viable in the face of some new technology then eventually it will get replaced (see SpaceX) but if it is "good enough" compared with the available alternatives then there is no point in reinventing the wheel. SRBs may not be perfect but they demonstrably have been economically useful.
I'm not arguing for or against SRBs but merely pointing out that if the expensive work of development has already been done then it makes sense to keep using them until something truly better comes along to replace them in the market. Whatever replaces them has to provide a substantial cost/performance savings or there is little point.
Did anyone seriously think they would kick the thing off on time? This is a govt. project.
You say that as if private enterprise projects never miss a deadline...
SLS has always been a make-work program to preserve legacy jobs at Space Shuttle contractors.
Perhaps in part but it also serves a few other purposes. Probably the most important one is that it gives NASA a path to getting heavy lift capabilities in the event that the private enterprises working on the problem fail. It's a hedge of a sort, albeit an expensive one. Let's say hypothetically that SpaceX cannot get their Falcon Heavy to work for some reason. If NASA put all their eggs in that basket they could reasonably end up with no heavy launch vehicle. With SLS in the works NASA won't find themselves without options no matter what the private sector does.
Remember that as recently as a few years ago it wasn't at all clear that private companies like SpaceX would be as successful as they have been so far. It was uncharted territory and when you go into uncharted territory it's sensible to have a backup plan in place just in case things go wrong. Things are looking better by the day for private launch companies but there is still time for things to go tits up before SLS is operational.
I have a running bet with some friends on how many times the SLS will fly (if ever). My money's on two flights before it gets the axe.
I think it will depend heavily on how successful companies like SpaceX and Blue Origin turn out to be. You may very well be right but I would regard that as a best possible scenario. If SLS ends up seeing a lot of use it means that SpaceX and the rest failed.
Did anyone seriously think they would kick the thing off on time? This is a govt. project.
It's not like it's rocket science or anything... oh wait.
That's not the reason you don't use it for a first stage. The disadvantages of hydrolox (which are numerous) are offset by its incredible specific impulse. But for a first stage, specific impulse doesn't matter that much, while thrust matters a lot. Thrust is in large part proportional to fuel density, as a turbopump sweeps out a fixed volume per rotation, so the denser the fuel, the more mass (and generally all else being equal, energy) it pumps per rotation.
Another aspect is that first stages are big, meaning that cost is more important than specific impulse. By contrast, when dealing with an upper stage, a small increase in mass has a huge increase in first stage size, and since first stages are so large and expensive, that's a big cost. So you generally want a higher ISP upper stage. With the caveat that "storability" requirements for engines that need to restart can shift the balance; because hydrogen is so deeply cryogenic it's difficult to store for protracted lengths of time. Also, the longer you plan to have a stage in usage without maintenance, the more you tend to favour simple propellants over high performing ones, particularly when you're dealing with small, light engines. So for example if you have an interplanetary probe you'll tend to favour a self-pressurizing hypergolic system so that you only have to rely on a couple valves working, even though self-pressurizing propellant tanks are heavier and hypergolics tend to be lower specific impulse. Engines that are smaller still are often monoprops for an even greater degree of simplicity.
"He's a liar whose lawyer is lying about his lying lawyer's lies."
Solids really aren't that bad when reusability isn't a concern. They're very high thrust, which is exactly what you want out of a booster, and they're structurally very simple. Their low impulse and high structural mass are not particularly important aspects for boosters. Reuse of solids however gains you very little, because there's so much work in refurbishing them.
"He's a liar whose lawyer is lying about his lying lawyer's lies."
This is why you set goals and let the scientists & engineers figure it out. When Apollo was built we didn't have Congress constantly dictating to NASA how it should be built, where it should be built or making design decisions. Fast forward to the 21st Century, we have endless committees getting nowhere with a constant tug of war on where components should be built and by whom.We've laid off the core of NASA who knew how to make the shuttle work and yes, regrettably we've had to spend tax dollars on busy work to keep ATK and others from going out of business.
In the meantime, ISS manned missions will be handled by the Russians who are our sometimes on again/off again friends. Now, because of these relationship issues, do any of us believe that the costs of doing business with the Russians won't significantly increase over the next few years? The ISS will be shuttered before it's end of life in 2024, another multi-billion dollar boondoggle that now the US can't fully support yet we provided most of the funding for. Bravo!
After billions spent on Orion/SLS, we still have no way to get our astronauts into LEO much less beyond. Didn't we win the race to the moon?
Harrison's Postulate - "For every action there is an equal and opposite criticism"