NASA Space Launch System (SLS)

merriman said:
Challenger

David

Wow, so ONE failure qualifies as "never do it again"? I guess you walk everywhere then right? I mean people have died in cars, planes, trains, ships, you name it. Clearly they're not to be trusted. Furthermore, the failure wasn't a technological one, it was a human one. They "put on their manager hats" and decided to launch anyway against the recommendation of the engineers. Now if you'd said, "rough ride" you might have been onto something. (Interior footage of launch with the astronauts bouncing around like bugs in a jar while the boosters are firing and suddenly goes to Bentley-smooth once they're under liquid only. )
 
RyanCrierie said:
sferrin said:
Falcon Heavy is only about 1/2 - 1/3 of an SLS.

SLS is only going to be about 70 metric tonnes (Block I), unless lots of expensive upgrades are funded for continued block development; like Block IB's EUS, which would bring it up to 105~ mt.

FH initially was about 50 mt, but some rumors indicate it may be now 60 mt after various upgrades over the years to the F9 cores (v1.0 to 1.1 to Full Thrust).

Falcon Heavy might cost $100-150 million to launch (who knows at this point); while SLS conservatively would cost between $500m and $1B to launch.

At this point, things are starting to swing to SpaceX, as they've done things thought "impossible", like recovering a spent first stage via retropulsive flyback; so their "believability quotient" has gone up versus what it was when they initially started Falcon Heavy.

Thought I saw 150 tons somewhere but that might have been for the previous iteration, that was cancelled.
 
130+ tons is with the following upgrades:

EUS (Exploration Upper Stage) -- this is funded and under development for SLS Block 1B, which will fly EM-2. Could be cancelled between now and 202x.

Advanced Boosters (Solid or liquid) For Block 2 onwards.

They should just have gone with the kerolox Saturn V style inline back in 2011; but oh well.
 
merriman said:
Yes. 1986.

Does time attenuate fact? Are you suggesting that The Great Chicago Fire is, today, not so 'great' because it happened so, so long ago?

David
Please your comment was not 'just' to reflect on the Challenger disaster it was to make a 'judgement' that solid rockets are incompatible with manned space flight.

Have fire code regulations and material technologies and firefighting techniques and technologies changed since the Great Chicago fire? Has there been other major city fire disasters on the scale of the Chicago fire?

Your statement about Challenger would be the same as if you said "Because of the Chicago fire we shouldn't build or live in any large cities" disasters just waiting to happen. Silly comparison isn't it?
 
It's not just that, but solids impose a huge fixed load onto facilities -- for example, you have to treat them as LOADED explosives all the way through processing and launch -- this places limitations on what you can use / put into the VAB, for example.

Plus, solids are pre-loaded, which places great stress onto the crawler-transporter which has to move the fully loaded mass to LC-39; as opposed to a liquid rocket, which can be moved empty, and fuelled on the pad.

These aren't major problems with the smaller SRBs used by Atlas V and Delta II, but become serious with the huge ones used by STS/SLS.
 
RyanCrierie said:
It's not just that, but solids impose a huge fixed load onto facilities -- for example, you have to treat them as LOADED explosives all the way through processing and launch -- this places limitations on what you can use / put into the VAB, for example.

Plus, solids are pre-loaded, which places great stress onto the crawler-transporter which has to move the fully loaded mass to LC-39; as opposed to a liquid rocket, which can be moved empty, and fuelled on the pad.
So then what are the advantages of solid rockets? Why would NASA persist in using them if liquid boosters would be such a easy improvement?
 
So then what are the advantages of solid rockets?

Supposedly shares infrastructure costs with ICBM program, allowing cheap thrust. Not much of an issue anymore with our present ICBM/SLBM program.

Why would NASA persist in using them if liquid boosters would be such a easy improvement?

SLS is essentially a jobs program now, to be honest, as we grind on year after year with no launch in sight. For something that was supposed to use "off the shelf" components; it's taken an awful long time to develop.
 
RyanCrierie said:
So then what are the advantages of solid rockets?

Supposedly shares infrastructure costs with ICBM program, allowing cheap thrust. Not much of an issue anymore with our present ICBM/SLBM program.

Why would NASA persist in using them if liquid boosters would be such a easy improvement?

SLS is essentially a jobs program now, to be honest, as we grind on year after year with no launch in sight. For something that was supposed to use "off the shelf" components; it's taken an awful long time to develop.

Sad that it's taking longer to do the SLS with "off the shelf parts" than the original Apollo program. ::)
 
RyanCrierie said:
It's not just that, but solids impose a huge fixed load onto facilities -- for example, you have to treat them as LOADED explosives all the way through processing and launch -- this places limitations on what you can use / put into the VAB, for example.

Plus, solids are pre-loaded, which places great stress onto the crawler-transporter which has to move the fully loaded mass to LC-39; as opposed to a liquid rocket, which can be moved empty, and fuelled on the pad.

These aren't major problems with the smaller SRBs used by Atlas V and Delta II, but become serious with the huge ones used by STS/SLS.

IIRC that was one strike against the Ares V. Too heavy for the crawler.
 
RyanCrierie said:
They should just have gone with the kerolox Saturn V style inline back in 2011; but oh well.
They tried, Congress torpedoed the idea because it wasn't close enough to STS for them.
 
It's interesting to go back to the first posts in this thread c. 2011 and consider what's happened since then:

Back then, Falcon 9 v1.0 had flown just twice; and the Dragon just once, where the Dragon did nothing but float around and validate various data before re-entering.

Since then, we've had Space X retire the Falcon 1.0 after five launches for the Falcon 1.1, put up six straight CRS successes before CRS-7 blew up; return to flight following the CRS-7 failure, introduce the Falcon 1.1 FT, and conduct a two year campaign (2013-2015) to return to earth a flown booster stage following a successful orbital launch.
 
blackstar said:
But a kerosene (RP-1) powered first stage was never an option for a bunch of reasons, including the fact that the pads have hydrogen plumbing but have not had kerosene plumbing since the 1970s, so choosing a kerosene engine would have required even more ground infrastructure changes.

Saturn V RP-1 plumbing was abandoned in place, not torn out.

The RAC-2 RP-1 launcher(s) won on economics and performance, but politics dictated RAC-1 Shuttle "Derived" had to win.

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20120013881.pdf
RAC-2
 
sferrin said:
merriman said:
Falcon-heavy and the SLS are in the same class, right? If not, BFR is only a few years away. I suggest we hang fire on the SLS and leave those warehoused SSME's be. We've demonstrated that solids and humans don't mix. What the hell are we doing?

David

Falcon Heavy is only about 1/2 - 1/3 of an SLS. Solids and humans don't mix? Uhm, wut?

53mT as on their site is an unchanged figure from 2011. Since then F9 is now able to lift more than 2 times to orbit vs v1.0 and hence 53mT is waaay lowballed for FH. It should be very fairly close (within 10-20%) of SLS Block 1 now. But LEO figures is not what matters here - SLS has by far higher performance upper stage.

Price for expendable FH was quoted as 135mil on their site previously but that figure is now removed, the price is likely to be between 135-150mil. Supposedly we might see updated FH data next week.
 

1. Fuel switch at the pad isn't a big deal. SpaceX is going to launch a kerosene vehicle from the other Shuttle pad and they sure as hell aren't spending what SLS is getting every year for ground ops.

ULA will also add methane supply to the pad they will launch Vulcan from.

2. Part of the plans in the Obama space policy of FY2011 saw the funding of a large hydrocarbon booster engine, aka an RD-180 replacement. It would have been eligible for HLV designs in their 2015 HLV design selection date. SLS displaced Obama's space program plan.
 
SLS development cost: $10Billion (just the booster). All tax paid. Each launch costs between $1Billion - $2Billion.

Falcon Heavy cost: zero (funded out of Spacex private R&D).

If SLS were privately funded I would be rooting for them but skeptical of their business plan.
 
blackstar said:
But as you note, payload to LEO is not the relevant measure, and I think somebody calculated that SLS can throw something like 4-5 times beyond LEO.

50 to 60 metric tons is a pretty powerful Earth Departure Stage; and even if Falcon Heavy still ends up costing $200m a launch, it's still going to be significantly cheaper than SLS, allowing Earth Orbit Rendezvous missions.

We'll get the new specs soon, but Falcon Heavy is the fanboy's favorite paper rocket, because they always assume the most optimistic aspects about it and disregard the rest. (I haven't seen anybody who makes a big deal out of SLS launch date slippage mentioning that FH was supposed to be flying three years ago).

SLS was to use "proven" shuttle technology, and was nothing special sizewise for the big primes who after all, have been building SLS-sized rockets since 1966; with a brief interruption from 1970ish to 1981. So why is it taking so long to get it to launch; particularly after it had been cut down to using off the shelf parts wherever possible (Delta IV upper stage, final flight STS SSMEs, left over SRB segments remanufactured from STS, etc) and prolonging all new stuff like advanced boosters and EUS to well into the 2020s?

By contrast, SpaceX took only about two years to accomplish the impossible, landing a booster stage on a landing pad after an orbital launch.

EDIT: Yes, I know rockets aren't legos; they had to do a bit of work on the SSMEs due to the increased head pressure from SLS' core stage being significantly taller than the STS ET...
 
I know I probably do sound like a SpaceX fanboy, but right now as of early 2016; their claims for Falcon Heavy are looking much more credible than they did back in 2011; when they were still a NuSpace upstart with very little booked feats to their name.

Now; they're pretty much one of the leading LPRE facilities in the world -- their own website makes the point clear:

To date, eighty Merlin 1Ds have launched, exceeding the propulsion heritage of the RS-68/68A engine (41 flown) on the Delta and the RD-180 engine (55 flown) on Atlas variants.
 
sferrin said:
RyanCrierie said:
So then what are the advantages of solid rockets?

Supposedly shares infrastructure costs with ICBM program, allowing cheap thrust. Not much of an issue anymore with our present ICBM/SLBM program.

Why would NASA persist in using them if liquid boosters would be such a easy improvement?

SLS is essentially a jobs program now, to be honest, as we grind on year after year with no launch in sight. For something that was supposed to use "off the shelf" components; it's taken an awful long time to develop.

Sad that it's taking longer to do the SLS with "off the shelf parts" than the original Apollo program. ::)

Absolutely...

All the decisions that have been made with respect to rocket design selection, re-use of 'existing parts', etc. have all been POLITICALLY mandated, not decided by good engineering...

SLS is a jobs program designed to keep the main shuttle contractors happy, nothing more. The main beneficiary is ATK for their solid boosters...

Later! OL J R :)
 
Moose said:
RyanCrierie said:
They should just have gone with the kerolox Saturn V style inline back in 2011; but oh well.
They tried, Congress torpedoed the idea because it wasn't close enough to STS for them.

Because it wouldn't reward ATK with huge contracts for their solid boosters, which in fact will be flown in EXPENDABLE mode and allowed to impact and sink after every flight now, instead of being recovered and reused as they were in the Shuttle program... eventually necessitating the rewarding of a huge new development contract to ATK to develop advanced throw-away boosters with expendable composite casings.

It's all about the politics, NOT the engineering... Why I've come to consider NASA's manned space program something of a joke... a very expensive bad joke, but a joke nonetheless... it's a political animal, nothing more.

Later! OL J R :)
 
http://www.sciencealert.com/8-charts-reveal-the-crazy-numbers-behind-nasa-s-new-monster-rocket
 
It’s big and impressive but what are we going to do with it? Going to Mars with our current economy is politically improbable. Going to the moon can’t generate or sustain a significant level of support and would still be exceedingly expensive if carried out in the normal NASA process. Capturing asteroids has failed to capture imaginations. What would be done in near Earth space that couldn’t be done significantly cheaper with smaller boosters? Using a monster rocket to launch cubesats invites ridicule (whether or not it’s merited). If a giant booster could reduce payload costs to $100/lb then you could open up the potential of creating/servicing a space tourism business but even at just $1Billion per launch (it’s probably higher) this would work out to $7100/lb. It won’t happen but my preference would be to terminate NASA’s manned spaceflight program and replace it with a single mission of pursuing all possible technologies that significantly reduce launch costs to a level that enables mass access to space. It would be interesting to "poll test" this idea so some politician might think about it.
 
If only NASA had stuck with the NACA mission -- comprehensive aero(space) research. Government built the infrastructure (wind tunnels, test stands, university grants, etc.) and defined areas of scientific investigation. Nothing else. Where's Vannevar Bush when you need him!

Once NASA got into the spacecraft production and launch business this government agency was doomed to die at the hands of the self-serving political 'leaders' and bureaucracy. An agency that puts 'safe' and job security ahead of progress. Today NASA is a magnificent white-collar government works program; welfare for accomplished, uninspired drones.

Not so with profit oriented spacecraft builders and operators (however, I choke back a primal scream as I remind myself of the attenuating 'work' the crony capitalists -- the 'legacy' space contractors -- have done). Look at the age and enthusiasm of the start-up rocket guys. Now, take a look at a group photo of NASA administrators and 'researchers' -- bunch of old guys in suits more worried about job retention than advancement of the craft.

NASA. Practitioners of the old rocket-as-expendable-ammunition school (The agencies brief embrace of Shuttle a bust). Once on the public dole it's much easier to embrace the tired and true and not expose yourself by engaging in daring, adventurous activity.

David
 
merriman said:
1. If only NASA had stuck with the NACA mission -- comprehensive aero(space) research. Government built the infrastructure (wind tunnels, test stands, university grants, etc.) and defined areas of scientific investigation. Nothing else. Where's Vannevar Bush when you need him!

2. Once NASA got into the spacecraft production and launch business this government agency was doomed to die at the hands of the self-serving political 'leaders' and bureaucracy. An agency that puts 'safe' and job security ahead of progress. Today NASA is a magnificent white-collar government works program; welfare for accomplished, uninspired drones.

3. Not so with profit oriented spacecraft builders and operators (however, I choke back a primal scream as I remind myself of the attenuating 'work' the crony capitalists -- the 'legacy' space contractors -- have done). Look at the age and enthusiasm of the start-up rocket guys. Now, take a look at a group photo of NASA administrators and 'researchers' -- bunch of old guys in suits more worried about job retention than advancement of the craft.

4. NASA. Practitioners of the old rocket-as-expendable-ammunition school (The agencies brief embrace of Shuttle a bust). Once on the public dole it's much easier to embrace the tired and true and not expose yourself by engaging in daring, adventurous activity.

Nonsense. NASA =/ SLS
The post is nothing but an idiotic rant.

1. And we would be way behind. NASA enabled many of the space systems used today. Spacex wouldn't exist except for NASA

2. Back off! You really don't know what you are talking about. As for wide sweeping stereotypes there are many when it comes to submariners that are more true.

3. Commercial operations have no need for scientific spacecraft, so how would space exploration be done?

4. Launch vehicle reuse has yet to be proven as cost effective.
 
Great, got my own personal stalker. Neat! Welcome aboard my fan-base, pal. Kisses.

David
 
merriman said:
Great, got my own personal stalker. Neat! Welcome aboard my fan-base, pal. Kisses.

Has nothing to do with "stalking", it was just a simple google search on your name and third hit was sub drivers forum. What did you expect, especially when your statements are unsubstantiated? But then again, it is all about the kisses for you submariners.
 
Exploration Mission 2 (EM-2) and Asteroid Retrieval Mission (ARM) are the only manned missions for Orion/SLS in 2020s decade? And if yes, can this space system be sustainable with a fly rate so low?

(Which mission, and when after ARM?)
 
carmelo said:
Exploration Mission 2 (EM-2) and Asteroid Retrieval Mission (ARM) are the only manned missions for Orion/SLS in 2020s decade? And if yes, can this space system be sustainable with a fly rate so low?

(Which mission, and when after ARM?)
Over at NSF they're discussing internal discussions (yes, that's a weird sentence) going on at NASA to fill out the SLS manifest with unmanned launches. A flight rate of 1 SLS a year is painfully low but would probably keep the booster viable for the whole decade.
 
carmelo said:
Exploration Mission 2 (EM-2) and Asteroid Retrieval Mission (ARM) are the only manned missions for Orion/SLS in 2020s decade? And if yes, can this space system be sustainable with a fly rate so low?

Considering that the 2020s are still a few years away, I think it's premature to act as if we know--or if NASA is expected to know--just how much it will do in the 2020s. We cannot predict the entire decade at this point.
 
http://gizmodo.com/yup-the-space-shuttle-engines-still-work-1764185832
 
https://science.slashdot.org/story/16/03/29/0446213/new-nasa-launch-control-software-late-millions-over-budget

(Note, not quite objective.)
 
Grey Havoc said:
Pardon my cynicism with respect to the current administration's posture regarding manned exploration, but I have always thought the asteroid mission and the stated goal of skipping the Moon for manned flights to Mars was simply a way for them not to commit any money beyond the bare-minimum to manned exploration.

The asteroid mission serving the purpose of a seemingly lofty goal - that came with the added benefit of not requiring the development any new flight hardware and infrastructure beyond that already being developed for Orion/SLS. Then the Mars program being the "bridge too far" that would solely exist in the form of PowerPoint and through the sound of lip-service.

We've been to the Moon. We have a good idea of all the additional hardware and infrastructure required to develop a robust Moon exploration program because of our prior experience. Which is exactly why I think this administration put the kibosh on the Constellation program. That money could be used to enrich the administration's constituency, and pie-in-the-sky "goals" that replaced Constellation cost nothing more than words.

Again, pardon my cynicism.
 
Grey Havoc said:
Boxman said:
Again, pardon my cynicism.

No apologies necessary, in fact it's well justified I fear.

Competely. I still haven't heard a compelling case for cancelling Ares only to recreate it (with years and billions wasted) and calling it "SLS".
 
sferrin said:
Grey Havoc said:
Boxman said:
Again, pardon my cynicism.

No apologies necessary, in fact it's well justified I fear.

Competely. I still haven't heard a compelling case for cancelling Ares only to recreate it (with years and billions wasted) and calling it "SLS".
It was never planned for that to happen, the Administration and NASA leadership didn't plan for the new Launcher to just be "An Ares by any other name" when they killed A-I and A-V. If they had known that Congress would take a "thou shalt use SRBs and HydroLox and thou shall not compete these contracts" hard line, they probably would simply have gone with "Area V Lite" and called it a day.
 
Boxman said:
Grey Havoc said:
Pardon my cynicism with respect to the current administration's posture regarding manned exploration, but I have always thought the asteroid mission and the stated goal of skipping the Moon for manned flights to Mars was simply a way for them not to commit any money beyond the bare-minimum to manned exploration.

The asteroid mission serving the purpose of a seemingly lofty goal - that came with the added benefit of not requiring the development any new flight hardware and infrastructure beyond that already being developed for Orion/SLS. Then the Mars program being the "bridge too far" that would solely exist in the form of PowerPoint and through the sound of lip-service.

We've been to the Moon. We have a good idea of all the additional hardware and infrastructure required to develop a robust Moon exploration program because of our prior experience. Which is exactly why I think this administration put the kibosh on the Constellation program. That money could be used to enrich the administration's constituency, and pie-in-the-sky "goals" that replaced Constellation cost nothing more than words.

Again, pardon my cynicism.

Oh, it's way beyond that--but you're in the right ballpark. I know various people on the edge of involvement with this who confirmed that the decision was not made with the input of any of NASA's in-house expertise. I'm pretty convinced that it was a PR exercise so that they could claim that they were pursuing a mission without actually doing it. They were not willing to spend the money up-front that was required (for instance, a better asteroid survey, which all the experts told them was needed to identify potential targets).
 
http://www.spacedaily.com/reports/International_Partners_Provide_Science_Satellites_for_Americas_Space_Launch_System_Maiden_Flight_999.html
 

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