What do you think of the SLS?

[Seret]

NASA is done wasting it's time, money and resources on repeating experiments in LKO and sending countless rovers* to Mars.

Nonsense, the Mars rovers have been hugely successful, and there are extensive future plans for further probes, rovers and a sample return. Experiments in LEO are also very sensible, we still have quite a lot of new kit to test before it'll be really safe to send humans on interplanetary missions.

[rkman]

they should just stick to the guns of the past! They worked perfectly fine and we could give them a facelift

SLS is more efficient than Saturn V, and it actually uses some Saturn V technology that has gotten a facelift.

[Wahgineer]

Nonsense, the Mars rovers have been hugely successful, and there are extensive future plans for further probes, rovers and a sample return. Experiments in LEO are also very sensible, we still have quite a lot of new kit to test before it'll be really safe to send humans on interplanetary missions.

Did you see the asterisk? That's called a footnote. Go down to the bottom of the page, find the sentence with an asterisk in front, and read it. Then you'll understand my point a bit better.

[rkman]

Did you see the asterisk? That's called a footnote. Go down to the bottom of the page, find the sentence with an asterisk in front, and read it. Then you'll understand my point a bit better.

*I'm not saying that the Mars rovers are useless, just that they can only do so much before it becomes impractical to use them.

Your point seems to be to counter your own claim that NASA has been wasting its time, money and resources.

Bonus question: how many NASA missions are not in LEO or on Mars?

Edited April 25, 2014 by rkman

[Klingon Admiral]

New Horizons and Cassini come to mind, and there is one around Jupiter as well iirc.

[78stonewobble]

New Horizons and Cassini come to mind, and there is one around Jupiter as well iirc.

Dawn, Messenger, still listening to voyager once in a while... SOHO, Stereo and other assorted probes aimed at investigating the sun... James webb telescope and others that we might want to put a little further away than LEO.

[Seret]

Did you see the asterisk? That's called a footnote. Go down to the bottom of the page, find the sentence with an asterisk in front, and read it. Then you'll understand my point a bit better.

Lol, I managed to detect your little caveat just fine thanks. I don't think it really adds weight to your point though, does it? On the contrary, I think you realised you'd said something a bit ridiculous and tried to back away from it a bit.

I get it, you like manned exploration. That's understandable, it's romantic and inspires all sorts of warm fuzzy feelings. But that's not how priorities in space exploration are set. Maximum science out to money in ratio is the hard-nosed reality of it. Which is why SLS will struggle, it costs a lot and doesn't have much to do. They either need to find some payloads for it or cancel it now before too much more money is spent.

[78stonewobble]

Lol, I managed to detect your little caveat just fine thanks. I don't think it really adds weight to your point though, does it? On the contrary, I think you realised you'd said something a bit ridiculous and tried to back away from it a bit.

I get it, you like manned exploration. That's understandable, it's romantic and inspires all sorts of warm fuzzy feelings. But that's not how priorities in space exploration are set. Maximum science out to money in ratio is the hard-nosed reality of it. Which is why SLS will struggle, it costs a lot and doesn't have much to do. They either need to find some payloads for it or cancel it now before too much more money is spent.

Well you could also launch unmanned stuff on the SLS. Ie. hubble replacement with say an 8 meter primary mirror versus the 2,4 meter mirror on hubble.

[Albert VDS]

The SLS is a good idea. I'm glad NASA choose for an actual rocket.

Comparing the Saturn V with SLS isn't really fair. It's like comparing a tube with an LCD TV.

Imagine what the Saturn V might have evolved into if it was kept in favor of the Space Shuttle.

It might have become a better rocket than what they say the SLS is going to be.

[KASASpace]

I did the same thing in Kerbal Space Program, and I am happy with my results. My similarly-developed universal interplanetary tug system can put 6 Kerbals or ten tons anywhere in the Kerbolar system.

Yeah, but KSP has time-warp. I wish IRL had that feature.....

Why were the papers not kept? O_O

The manufacturers of the engines (IE the F-1) were ordered to keep the designs. They didn't really do that well at it.

The same could be said of Delta-IV.

No, that's no where near the payload of the SLS. SLS will have an LH2 stage that will be just as big or bigger than the first stage of the S-V.

The funding of exploding craft does not necessarily evaporate: Apollo 1 killed its crew, and Apollo 11 walked on the Moon.

-Duxwing

Umm, not to be the contrary, but that was when NASA was heavily committed. Now, NASA has a shoestring budget, one flop, and it goes down the toilet. It's mainly a political thing. Plus, Apollo 1 was a capsule fire, not an LV explosion.

[Woopert]

I don't know why people say this. There were terrible tragedies, yes, but it worked perfectly fine otherwise. It was a (relatively) cheap way to go to space. Now SLS is going to be that.

It was not really that cheap. And SLS is not replacing the Space Shuttle, it is a heavy lift rocket similar to payload capacity of the Saturn V (Block II at least). Dream Chaser, Dragon, and CST-100 are the replacements for the Space Shuttle.

I'm gonna say it now, the sls, is the ugliest rocket ever created... bad name as well. Plus the solild boosters "I got an idea lets kill another crew". I doubt it will cost what they say, probably over 3-4 times as much.

I thought the same thing, but with a proper and traditional launch escape system, they SHOULD be able to abort rather quickly if they solid rocket boosters fail (which isn't likely, they've learned a lot about O-rings since then; another safety "feature" is that the Orion MPCV is not piggybacked, so there won't be any foam coming off and knocking away the heat shield... and the heatshield is already not exposed like the Space Shuttle's wings.

I thought it was pretty cool that the J-2 engines on it were the same as the main engines on the Space Shuttle, and using a cluster of four of them was something I had never thought of.

Haha, you got those mixed up a bit. The J-2 was used on the Saturn V second stage in a cluster of five, and a single J-2 on the third stage. The Space Shuttle used SSME's (renamed RS-25 for the SLS), and they're using four (you're correct ) on the core stage. Block II of the SLS will use two J-2X engines (upgraded J-2 enginees) on the second stage (or third, counting the boosters). The F-1 engine from the S-IC stage (Saturn V first stage) is being modernized and made more "reliable" (even though the F-1 had no failures) and turned into a less complex (simpler) design. It's called the F-1B and is being developed by Dynetics and Aerojet Rocketdyne (formerly Pratt and Whitney Rocketdyne when development began).

No, that's no where near the payload of the SLS. SLS will have an LH2 stage that will be just as big or bigger than the first stage of the S-V.

Space Launch System Block II upper stage will be 8.4 meters wide. The first stage of the Saturn V was 10.1 meters wide.

The SLS is not a waste of time, not at all. It is another step in the right directions for Mars, which if we don't get there, we are failing. Falcon Heavy doesn't have the Oomph, and the Falcon XX and such aren't even being developed, they're just concepts. They actually ARE making the SLS, it's going to happen.

[R0cketC0der]

Falcon XX is an interesting concept, but it isn't getting any funding currently and we don't even know anything about the development of its Merlin 2 engines, so it's pretty unlikely that it will become reality anytime soon.

However we know that SpaceX is developing the raptor engines and the only planned vehicle they have yet spoken about that would use these engines is the mars colonial transporter - a vehicle that could lift over 100 tons to mars. It will still take several years to even get to a point when they can announce an ETA.

This is still all only on paper, but if it will get operational and fully reusable, SLS would loose all hope for any mars missions. Things that SLS would set on mars would be able to be loaded as a secondary payload on the mars colonial transporter.

[check]

Falcon XX is an interesting concept, but it isn't getting any funding currently and we don't even know anything about the development of its Merlin 2 engines, so it's pretty unlikely that it will become reality anytime soon.

I don't think it's that far off.. maybe by the end of the decade. Falcon 9 first stage recovery should be demonstrated by years end... reusability by Q1 of 2015. Abort tests for Dragon rider should be done by this year. Falcon Heavy demo flight by Q1-Q2 of 2015... Maybe a crewed Dragon Rider next year. All that is happening within the next year. After that, I could see a large part of r&d shifting to Merlin 2 and Falcon X/XX.

[Nibb31]

That schedule is way too optimistic. SpaceX has yet to recover a booster. After that, it will be a while before they get to a stage where they are confident enough to reuse it. They will need to tear down the first couple of recovered stages, x-ray the parts, check everything, and rebuild and test them. They will also need to find a customer who is actually willing to risk their payload on a reused stage. NASA won't, and I don't think DoD will either. That kind of limits the point of reusability.

And again, Falcon XX will only be built if there are customers willing to fly their birds on it. There are no payloads for it and customers aren't really queuing up with 100 ton payloads on the launch market.

[Lexif]

you show your ignorance.

Concorde "only killed 1 crew and load of passengers". That was considered enough to order the type retired.

Why? Because there were so few of them.

2 hull losses out of 6 or so built is a lot, it's 1/3 of the fleet.

You should not use bold statements about the ignorance of others and then expose your lack of knowledge in the next sentences, that's pretty embarassing.

[Dodgey]

........They will also need to find a customer who is actually willing to risk their payload on a reused stage. NASA won't, and I don't think DoD will either. That kind of limits the point of reusability.............

So I guess the STS was useless than?

[Duxwing]

Or it might not, that's my point. As I said up at the top: "if you build it, they will come" is not a sensible way to do business.

We can speculate forever on what Congress' motivation might be, and payload manufacturers might be nervously standing around, pointing at and whispering about the guy with the blue patch on his shirt and the model of a huge rocket on his desk, wondering whether he can build it and whether they therefore can sleep at night after building payloads for it; the patch-and-rocket guy likely has already asked the huddled crowd whether they would if he succeeded. Less allegorically, NASA likely has done market research that indicates demand for the SLS.

The only reason they should even be building a giant lifter is if they had some giant payloads they absolutely had to launch. That's why we built the Saturn V, because it was an integrated part of a programme that required it. I'm not quite sure what SLS is being built for.

The SLS is for Beyond Earth Orbit payloads that lesser rockets cannot lift.

I don't think anyone is seriously thinking about sending one to LKO ;-)

*snickers* Playing a little Kerbal Space Program, I see...

If congress wants to send men to Mars, then they'd better start allocating a budget. It would take at least 10 years to develop the technology and another 10 years to develop the vehicles to go there, and that's if they started allocated funds right now, which they aren't.

That estimate seems extreme. The Martian technology (I feel giddy saying that phrase) would be developed within some mass limit, enabling the transfer vehicles' simultaneous development.

SLS can't sit around for 20 years waiting for a payload, and any interim mission hardware requires even more funds, which only pushes Mars back another 10 years.

It need not, and how would interim mission hardware push back a mission that would have, by definition, already begun?

It is an overly specialized launcher. It's specialized in 60 to 130 ton payloads which don't exist. You don't get more overly specialized than that really.

Those payloads are already being developed.

-Duxwing

[cantab]

So I guess the STS was useless than?

Not the same thing at all. The Shuttle was always meant to be reusable and they were never going to make a new Shuttle just for one launch.

With Falcon, customers will have a clear choice: Insist on a brand-new rocket for their payload and accept the possible higher cost, or let SpaceX use a reused rocket and negotiate a lower price. Commercial buyers will estimate what they feel is the extra risk of failure with a reused rocket and weigh the losses of such a failure against the cost savings. Their estimates may or may not be in line with SpaceX's.The insurers will have a say too. The military, on the other hand, will probably just take the brand-new rocket, cost be damned. NASA's payloads are probably more expensive and less replaceable themselves than typical commercial satellites so they're also likely to play it safe.

[Seret]

The SLS is for Beyond Earth Orbit payloads that lesser rockets cannot lift.

Well obviously, yes. But do you think it makes sense to simply assume that such payloads will appear once the rocket is ready? What happens if they don't? What if NASA ends up using STS for ISS crews and not much else?

[R0cketC0der]

Not the same thing at all. The Shuttle was always meant to be reusable and they were never going to make a new Shuttle just for one launch.

With Falcon, customers will have a clear choice: Insist on a brand-new rocket for their payload and accept the possible higher cost, or let SpaceX use a reused rocket and negotiate a lower price. Commercial buyers will estimate what they feel is the extra risk of failure with a reused rocket and weigh the losses of such a failure against the cost savings. Their estimates may or may not be in line with SpaceX's.The insurers will have a say too. The military, on the other hand, will probably just take the brand-new rocket, cost be damned. NASA's payloads are probably more expensive and less replaceable themselves than typical commercial satellites so they're also likely to play it safe.

The falcon 9 was also designed from the beginning with reusability in mind. The probability of a failure because something got damaged on a previous flight and the damage wasn't discovered won't be very much higher than the probability that some component got manufactured faulty. The space shuttle failures didn't have anything to do with the reuse of components and so it's unlikely that the falcon 9 will be more unsafe when reused.

[Duxwing]

Well obviously, yes. But do you think it makes sense to simply assume that such payloads will appear once the rocket is ready? What happens if they don't? What if NASA ends up using STS for ISS crews and not much else?

The payloads are already being developed.

-Duxwing

[R0cketC0der]

The payloads are already being developed.

-Duxwing

Which payloads are those? From what I know the only payload that is actually funded is Orion.

[Armchair Rocket Scientist]

Well obviously, yes. But do you think it makes sense to simply assume that such payloads will appear once the rocket is ready? What happens if they don't? What if NASA ends up using STS for ISS crews and not much else?

Not even NASA would use a vehicle with a 70+ ton payload capacity to deliver a 20 ton spacecraft to LEO. A man-rated Delta IV Heavy would probably work, but Dragon, Dream Chaser, or CST-100 would be much better suited for LEO taxi missions.

[deadshot462]

The SLS is a jobs program for former shuttle contractors to keep state constituents happy. Congress basically wrote the specs for the rocket, telling NASA they have to use certain shuttle-derived parts. Not much room for innovation there, which is NASA's job.

I wouldn't mind this if there were specific missions lined out or even payloads. Right now the only confirmed payload is the Orion capsule for a couple of test missions. Just for that, NASA could have used already available commercial rockets.

[Dodgey]

Not the same thing at all. The Shuttle was always meant to be reusable and they were never going to make a new Shuttle just for one launch.

With Falcon, customers will have a clear choice: Insist on a brand-new rocket for their payload and accept the possible higher cost, or let SpaceX use a reused rocket and negotiate a lower price. Commercial buyers will estimate what they feel is the extra risk of failure with a reused rocket and weigh the losses of such a failure against the cost savings. Their estimates may or may not be in line with SpaceX's.The insurers will have a say too. The military, on the other hand, will probably just take the brand-new rocket, cost be damned. NASA's payloads are probably more expensive and less replaceable themselves than typical commercial satellites so they're also likely to play it safe.

As R0cketC0der said, it was designed from the start to be reusable, the Shuttle accidents had nothing to do with detriment of parts over time due to being reused, what reason do you have to think that it won't be more reliable because it is being reused. In fact we have reason to think that it would be more reliable than the STS because the main components which are being reused do not have to survive reentry and are inherently less complicated than the entire STS system. What's your point? Because the customer has a choice between using a reusable rocket and using a one time use rocket they will just pay the extra to use the one time use? So if they had the same option with the STS would they of taken it?