what the new NASA Space launch system says to other rockets

[Aedile]

Rockets are actually less efficient while still below about 100m/s, so getting up to speed is a must (that's what SRB's are for)

I'd describe the NASA SLS as the upper limit of chemical rocket technology, I doubt there will ever be a larger rocket or one more powerful before some other technology completely replaces the need for such craft.

As for the KSP version, I describe it as beefy

In addition,

If we are talking about RL engines - Thrust increases with ISP, that is at sea level rockets have lower trust.

In KSP this is modeled wrong by varying fuel consumption. So you get more trust to begin with, and you burn fuel faster, so the use of SRBs is limited at best.

Also KSP provide constant trust (leading to huge spike in TWR at the end of their burn), while RL boosters can be designed with difference trust curve.

Edit - in this particular case 400kN per engine, or 1600kn together...

Edited April 11, 2014 by Aedile

[mellojoe]

I'd describe the NASA SLS as the upper limit of chemical rocket technology, I doubt there will ever be a larger rocket or one more powerful before some other technology completely replaces the need for such craft.

I think the only real innovation will be the ability to do true crossfeeding, like is predicted with the Falcon. Once this is repeatably achievable, we'll see bigger payloads to LEO using conventional rocketry.

Conventional rockets will probably always be initial stages. I think the real innovation will come from upper-stages and fuel depots. If you could park the fuel in LEO, thats much less weight sitting on the launchpad. Your payloads could effectively get bigger. Or a partial space elevator from LEO to Geostationary or beyond taking the place of upperstages. I see lots of innovation in the future in the upper edges of the atmosphere. But the initial stages consisting of sparks + fuel + blasting copious amounts of gasses out of a cylinder will probably remain supreme for a long, long time.

[godefroi]

I think the only real innovation will be the ability to do true crossfeeding, like is predicted with the Falcon. Once this is repeatably achievable, we'll see bigger payloads to LEO using conventional rocketry.

There's nothing preventing us from doing crossfeeding on a large scale right now. The only problem is that in real life, things like hoses, pumps, connectors, and valves all have weight, and failure rates which are >0. It's not beneficial enough in real life to risk your expensive payloads (and rockets).

[nadreck]

I'm just a lurker but that got me thinking - what delays does SLS project have? They're still on track with december 2017 lunch, AFAIK they concluded PDR and are preparing for 2015's CDR. On the other hand Falcon's Heavy first launch may slip from 2014 to 2015.

Well, first of SLS is a long delayed version of a similar plan that got mired in development (Constellation) and politics, the Orion Capsule that is supposed to integrate with SLS is facing delays, one test by 2 years. Finally, I would suggest that we talk again in 2017 and see where SLS is then (possibly the same place Constellation is now with a new paper tiger in the wings).

[deadshot462]

SLS, what DO you lift? Besides an Orion capsule?

[NovaSilisko]

By the way, some of the publically known info about SpaceX's beast: http://www.nasaspaceflight.com/2014/03/spacex-advances-drive-mars-rocket-raptor-power/

SLS, what DO you lift? Besides an Orion capsule?

If we're VERY lucky, a big fat probe to Europa.

[[email protected]]

A gigantic waste of money. Ten times the cost of the Atlas, at least twenty times the cost of the Falcon Heavy for only marginally better lifting capacity.

NASA has become so mired in bureacracy it is incapable of doing anything with reasonable efficiency to cost or time.

I firmly believe that the future of spaceflight must lie in private hands, as governments are too inept, corrupt, and stupid to do it anymore.

[Walker]

Well, first of SLS is a long delayed version of a similar plan that got mired in development (Constellation) and politics, the Orion Capsule that is supposed to integrate with SLS is facing delays, one test by 2 years. Finally, I would suggest that we talk again in 2017 and see where SLS is then (possibly the same place Constellation is now with a new paper tiger in the wings).

Thank you for your answer, I see your point. I my personal opinion we should also remember, that:

1. SLS isn't really a version of Constellation - it's LV construction program. This LV may be used for many different purposes (like shuttles were), e.g. flexible path missions. We may argue if Constellation's cancellation resulted in some “delay†of flexible path, but that's not a problem of SLS as a launch vehicle.

2. Orion has been facing delays, yes, but the capsule is not part of SLS program, but part of flexible path as one of SLS's possible "payloads". Also those delays result mainly from Ares I issues, that caused frequent redesigns of the capsule.

I don’t say that in 2017 we’ll see first launch of SLS, but I believe, that if it goes through CDR in 2015 (and stays funded) it will be launched no later than, I guess, 2018.

If there are some concerning issues with SLS, those would be IMO lack of payloads and destinations rather than engineering problems or delays.

[nadreck]

I don’t say that in 2017 we’ll see first launch of SLS, but I believe, that if it goes through CDR in 2015 (and stays funded) it will be launched no later than, I guess, 2018.

If there are some concerning issues with SLS, those would be IMO lack of payloads and destinations rather than engineering problems or delays.

You are welcome to your opinions, and in fact I would single handedly fly a Kerbal 1 person lander can all the way to Eloo to defend your right to those opinions, but one of them really does drip with irony to me: the lack of payloads for the SLS is a direct result of the waste of billions on the Constellation project, the SLS, the Orion capsule. Imagine how many science payloads they could have built and provisioned with that sort of money. If they had poured 25% of it into SpaceX and one competitor in the same time frame the other 75% could have gone to manned and unmanned missions for those vehicles (including the Falcon Heavy and probably the X with the Raptor engine) to carry.

[Captain Sierra]

SLS Block II- 130 tons to LEO

SpaceX Falcon XX- ~154.3 tons to LEO

SpaceX wins.

[Jouni]

SLS Block II- 130 tons to LEO

SpaceX Falcon XX- ~154.3 tons to LEO

It's actually 130 tonnes vs. 140 tonnes. Those non-standard tons some people use can be confusing.

The SLS Block 2 variant using boosters based on F-1 engines will probably go beyond 130 tonnes to LEO design target, if it's ever built. According to some estimates, it's going to be closer to 150 tonnes.

[samstarman5]

I am willing to bet there is more we can do yet with current liquid engine tech; it just requires enough motivation which is still lacking, at least as far as the government programs go. I am hoping the private sectors, like SpaceX, are really serious about getting themselves established with their space programs, as there is a ton of money to be made from space. As it is, iron alone is getting noticeably harder to find on terra firma without heading out to the ocean floor(which would be another worthy endeavour), and yet there is a ton of it floating up there in places the treehuggers could care less about. If there is money to be made in space, the private sector would definitely be motivated to build a better engine to get out of Earth's gravity well on a budget. That will be where more will come out of liquid engines.

[cantab]

The Falcon X and the Merlin 2 engine planned to power it are pretty much concepts at the moment. In terms of timescale for flying and likelihood of being built they're not at all comparable to the SLS, which is using proven in-service engine and booster designs (in Block 1 at least). (Not that SLS is guaranteed to fly, but I think it will at least once.)

[Rokker]

SLS, what DO you lift? Besides an Orion capsule?

Well, there are a number of possibilities, such as the largest space telescope ever, much more powerful than Hubble or JWST. There is also the possibility of Skylab 2: Electric Boogaloo, Skylab II would be located in the L2 Earth-Moon Lagrange point. There's also the asteroid capture mission, ya know, the whole reason for the ARM pack. A Mars sample return mission and Martian crew transfer vehicle. We could finally probe Uranus (lol) with a dedicated Uranus probe. The Bigelow Commercial Space Stations, and possibly a number of secondary commercial items acting simultaneously as ballast. Near Earth Asteroid missions are being looked at. Stuff like that mainly.

[MarvinKitFox]

What does SLS say to other rockets?

"Im more expensive than you, your family, and your whole neighborhood together."

"I can lift one fiftieth of an ounce per dollar" Theoretically, of course, in real life nothing has been lifted yet, aside from price.

"I don't exist yet, and may never "

"Everything I aim to (not) do has already been (not) done, by Constellation"

Edited April 16, 2014 by MarvinKitFox

[ZooNamedGames]

When speaking to the engines of the new SLS, most of you forget (unless they decided otherwise since I've read it) they're using the SSMEs instead of creating a who new engine for the program, because the idea and point of the program is to reuse existing existing technology.

We are planning on using the same SRBs from the SSs as well, because again, it is cheaper to remake existing technology than to completely design, test, manufacture and learn about new man rated engines work.

I can't remember, I might be thinking of an idea from a prior idea that has been thrown out, but they (were) planning to reuse the same SS EFT as well for the main fuel stage. So that would again reuse the same existing technology (I may be mistaken there).

The biggest goal of the Orion program is to "beyond LEO", as NASA has said a plethora of times. It's other goal is to reuse the existing technology to go where the SS couldn't.

[ScallopPotato]

I don't get where people are saying the SLS is being delayed and is over budget. AFAIR, the rocket is on time and on budget.

The SLS is really good, it's just that there may be better rockets than it.

I feel that there should have been a commercial heavy launch development program like there is for cargo and crew. If the commercial programs had been this current point back in 2010-2011, I think Congress would've felt confident in having a CHLVD (SDHLV vs SpaceX Falcon BFRs vs something else). But it is what it is.

[TechnicalK3rbal]

And then the BFE-5000 walks in and goes "So what'd I miss?"

Warning: Do not Google BFE-5000

[ZooNamedGames]

Warning: Do not Google BFE-5000

O.o what did you find?? Are you ok? Can I get you a new brain?

[TechnicalK3rbal]

O.o Can I get you a new brain?

Yes,,please....

[NASAFanboy]

Meh, I'm not impressed.

Is it really only that big?

I think I'll start working on a engine five times or twice as big if I ever bother to my 50+ unfinished modding projects in Blender. Or just that one, make it functional for 0.23.5, and upscale it in the configuration file.

I'll call it the BFE-Infinity.

Powerful enough to eat the fuel of a jumbo in a minute and the fuel of a new SLS tank on a minute and 45 seconds it mattered. It's going to reach escape velocity from Kerbol after a

Might have to make massive fuel tanks

[ZooNamedGames]

Yes,,please....

*smashes head open with a hammer*

*removes brain*

*puts a blender in*

*puts metal bowl as skull replacement*

*stitches together*

It's fixed! Your all better now...

*hands mirror*

[merendel]

I'll call it the BFE-Infinity.

Powerful enough to eat the fuel of a jumbo in a minute and the fuel of a new SLS tank on a minute and 45 seconds it mattered. It's going to reach escape velocity from Kerbol after a

Might have to make massive fuel tanks

Try KSP interstelar and use a thermal rocket on beamed power. pump 100gw or so into the network and you can burn out a jumbo in a couple of seconds. Last time I did it I had around 2 seconds of thrust, had reentry effects almost instantly and still got up over 20k ballistic despite the absurd drag. I dont think the engiens were still runing when it flew past the 1k mark.

[razark]

I don't get where people are saying the SLS is being delayed and is over budget. AFAIR, the rocket is on time and on budget.

Has it flown yet? Once it flies, then you can determine if it met budget and time goals. It is a government project, after all.

[ScallopPotato]

Has it flown yet? Once it flies, then you can determine if it met budget and time goals. It is a government project, after all.

The rocket goes through stages of development, and it's been hitting those milestones on time, so that's where the "on schedule" part comes from.