Poll

September 2027: will either, neither or both SpaceX's BFR and NASA's SLS be operational?

SLS will be operational, BFR will not.
23 (9.4%)
BFR will be operational, SLS will not.
131 (53.5%)
Both BFR and SLS will be operational.
79 (32.2%)
Both BFR and SLS will not be operational.
12 (4.9%)

Total Members Voted: 245

Voting closed: 10/30/2017 05:15 PM


Author Topic: 10 Years From Now: SLS vs BFR  (Read 27409 times)

Offline oldAtlas_Eguy

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Re: 10 Years From Now: SLS vs BFR
« Reply #80 on: 10/08/2017 04:32 PM »
Your views did a 360? So, back where you started. Sill not making much sense though, sadly.

Also, you don't test reliability in. It is designed in and then verified.



Exactly.  In order to get near perfect reliability, the design is going to have to iterate. 

But the tests to demonstrate the required reliability are going to need more than a couple thousand hours (which is typical). In other words, how long would reliability testing need to run to demonstrate a service life on Mars for about two years?

Demonstrating the required reliability to get to a moon base for 'just' 28 days would be quite a challenge.
The estimate I have for such manned testing occurring in LEO with small crew on-board (quick return to Earth if required because of any failures in any of the redundancy systems is 2 1/2 years. Which is any element of a redundant system fails but still leaves the system operable would still require a return. It is these failures while on-orbit that is being seeked. Between each test is the time it takes to determine and fix the root cause of the failure. Testing is iterated until the small crew is able to stay on-orbit in LEO (possibly L2 durring latter tests) for 1 year without any systems failing.

So the system would be qualified for long duration usage for such as a manned Mars flight after 2 1/2 years from first manned flight.

At that point usage for Lunar mission conveyance of larger crews (25) would not be out of question with stays on Lunar surface of 6 months as temp habitat for them.

Offline intrepidpursuit

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Re: 10 Years From Now: SLS vs BFR
« Reply #81 on: 10/25/2017 07:23 PM »
I voted BFR and not SLS. Though I think it is equally likely that they will both be "operational" as much as SLS is ever even planned to fit that term.
BFR has no bearing on SLS being canceled because SLS has no real purpose for BFR to usurp other than "creating jobs" which BFR will not do (in Alabama anyway). But, I think SLS can't survive past its first two launches because we already know there is not enough money for it plus a worthy payload.

BFR might have more bearing on whatever the next rocket is since a vague "mars rocket" or "moon rocket" claim is harder to make arbitrarily when there is actually an operation system laying around. Congress and NASA's engineers and mission planners (so Congress) have long since forgotten that was the stated purpose of Ares V and SLS respectively, despite NASA's marketing department's mindless droning about it. I just hope that makes the new jobs program go under a different budget so NASA can work on mars tech to put on BFR.

Offline Craftyatom

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Re: 10 Years From Now: SLS vs BFR
« Reply #82 on: 10/26/2017 03:22 AM »
I said BFR and not SLS, but it was a hard decision, and I don't put it far out from 50/50 between that and them both being operational.  I'm pretty sure BFR will be operating as an orbital launcher within the next 10 years (even a pessimistic take on schedule would have a hard time introducing that many delays without major changes to SpaceX's plans, imo), but SLS is a bit of a different beast.

I agree that SLS has its steadfast congressional proponents, and only exists today because of them.  However, I think that once BFR has any commercial mission complete - that is, someone buys a launch, pays SpaceX the money, and then gets their payload delivered to orbit for $X - it will be difficult to defend SLS in congressional hearings, even more so than it is now.  Keep in mind that many American news sites opposed to the party in control of Congress at the time will immediately run an article reading "the government is wasting your tax dollars on a rocket when they could be using BFR".

Shuttle was built because it was supposed to be cheap, but then it wasn't cheap so instead it was called assured American access, but then 51L happened so instead it was billed as "the manned American launcher" until its reputation as a manned launcher degraded and it was retired.  SLS will suffer the same fate: it was the "only manned deep space launcher" until it wasn't (see recent panels on Lunar economy, and SpaceX's moon flyby customer on FH), now it's "the only rocket big enough" until BFR or NA fly, and then...?  There are only so many metrics to measure a launch system by, and though you only need one to make a case, soon there won't be any left.  BFR will take the last leg SLS had to stand on.

So that's why I don't think SLS will be flying 10 years from now.  BUT, that said, I don't think Congress is going to roll over and hand SpaceX their launch contracts.  I think, in their infinite wisdom, the U.S. government is going to try and make NASA build a new launcher - SLS clearly isn't cutting it (note that some of its proponents may not be in office a decade from now), so NASA will be told to do it again, but better.  I'll let you imagine how that one goes.

I don't like saying that SLS is going away so soon, because it feels like wishful thinking, but perhaps the above scenario is proof that a future without it could theoretically still be incredibly bleak.
All aboard the HSF hype train!  Choo Choo!

Offline spacenut

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Re: 10 Years From Now: SLS vs BFR
« Reply #83 on: 10/26/2017 12:54 PM »
If SLS is to continue, I predict NASA will build kerolox reusable boosters for it with SpaceX landing technology.  They will probably use 5 AR-1's.  This would cost less in the long run.  They will probably expend the core, but, going back to the SSME, and either maybe parachuting them down.  It may lower costs, but still not be fully reusable.  If not it will be cancelled and NASA will use BFR for things they want to do in space.  They will have to design to fit the payload bay of a cargo BFR.  By then there will also be New Glenn and Vulcan for larger payloads, in space assembly of something. 


Offline Ronsmytheiii

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Re: 10 Years From Now: SLS vs BFR
« Reply #84 on: 10/28/2017 10:29 AM »
For SLS,  I think it will be flying in 10 years, but it will have on average at best one flight a year. I think NASA will delay the advanced booster competition, and as a result stretch out existing SLS launches. Then as new and bigger commercial lv's enter the market (Falcon Heavy, New Glen, and even Ariane 6) NASA will move payloads like Orion and resupply flights to the DSG and the moon to "supplement SLS". Eventually they will cancel the advanced booster competition, and simply end SLS after the current booster cases are expended, and will instead use New Armstrong and BFR.

All of which will take more than a decade, so I might be alone but I can easily see SLS flying in 10 years and BFR not.
« Last Edit: 10/28/2017 10:29 AM by Ronsmytheiii »
"Every vision is a joke until the first man accomplishes it; once realized, it becomes commonplace." - Robert Goddard

Offline darkenfast

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Re: 10 Years From Now: SLS vs BFR
« Reply #85 on: 10/30/2017 04:55 AM »
Thank you for participating in my poll and for the high-quality comments.  The poll will close tomorrow morning.

Offline oldAtlas_Eguy

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Re: 10 Years From Now: SLS vs BFR
« Reply #86 on: 10/30/2017 03:04 PM »
Even though SLS planning dates for launch events may be earlier, the actual occurrence of those launch events may never meet those dates. Having an earlier planning date when the event is several years away and in the case of all of the launch events possible planning dates (EM-1->Dec 2019 = 2+ years away, EC ->Jun 2022= 4.5 years away, EM-2 -> Jun 2023 = 5.5 years away) will help in minimizing slips. But that leaves what are the reality of when the high likelihood of those events occurring: EM-1 -> May 2020, EC -> Mid 2023, EM-2 ->Mid 2024. The first manned launch at 12+ years after program start and ~$40B spent SLS/Orion since SLS program started in 2012. The sad part is that Constellation could possibly have been done with that amount of time and money resulting in a 200mt cargo launcher not just a 100mt cargo launcher.

Online envy887

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Re: 10 Years From Now: SLS vs BFR
« Reply #87 on: 02/09/2018 04:51 PM »
Yeah you can split hairs to no end. No i don't think Atlas 552 can be called an operational capability quite yet. Dual engine centaur isn't a done deal.

If a thing flies more than 2 times, and has hit at least 1 flight a year cadence at some point, I'd say its properly operational.

Quote
Or are you saying that in the next 10 years no 30+ tonne capable rocket will achieve operational status anywhere in the world?

That is what I'm saying.

This seems like a terrible bet for you, since you can't win for 10 years. But if you really think it worthwhile, I'll bet 6 months of L2 membership (or equivalent value when the bet ends, but not more than $100 US). Conditions: a launch vehicle in a configuration nominally capable of 30,000 kg of separable payload to LEO must successfully fly 3 times including at least 2 times in less than 2 consecutive calendar years before today's date in 2027. And the vehicle can't be explicitly considered experimental, even if completing those flights. Once those flights are complete, I win. If the end date passes without those flights happening, you win. Good?

You are on.
That's one.
« Last Edit: 02/09/2018 07:42 PM by envy887 »

Offline DJPledger

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Re: 10 Years From Now: SLS vs BFR
« Reply #88 on: 03/01/2018 07:56 PM »
If SLS is to continue, I predict NASA will build kerolox reusable boosters for it with SpaceX landing technology.  They will probably use 5 AR-1's.  This would cost less in the long run.  They will probably expend the core, but, going back to the SSME, and either maybe parachuting them down.  It may lower costs, but still not be fully reusable.  If not it will be cancelled and NASA will use BFR for things they want to do in space.  They will have to design to fit the payload bay of a cargo BFR.  By then there will also be New Glenn and Vulcan for larger payloads, in space assembly of something. 
SLS likely to be cancelled long before 2027 with BFR flying frequently by then. If NASA wants to build kerolox reusable boosters for SLS then have them use 17-20 Merlins rather than 5 AR-1's. BE-4 more likely to fly than AR-1. Merlin already has an extensive flight history while AR-1 has not even reached full engine testing.

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