Quote from: drunyan8315 on 02/07/2018 09:39 pmHow can one discuss the relative merits of two rocket systems without acknowledging that one is throwaway and the other is reusable? The first SLS is going to go up in 4-5 years and then... it will be vaporized. Then you get to build another one.Again, SLS is a creature of politics, not sensibility. It doesn't matter that competing systems are reusable. That's not going to be a factor in deciding whether SLS will continue or not. And to be fair, SLS was bending metal before SpaceX started crashing boosters into the ocean; I'm not going to fault NASA for not pursuing reusability when they were clearly directed to build an expendable system in a relatively short time frame, and especially when their previous reusable system failed to live up to its promises regarding cost and turnaround time.
How can one discuss the relative merits of two rocket systems without acknowledging that one is throwaway and the other is reusable? The first SLS is going to go up in 4-5 years and then... it will be vaporized. Then you get to build another one.
Quote from: Chris Bergin on 02/07/2018 01:08 pmQuote from: Svetoslav on 02/07/2018 12:34 pmHow do you think the successful flight of Falcon Heavy will impact SLS? Will there be consequences? Will development of the rocket continue as planned, will the status quo will be maintained? Or is there any chance for the Adminstration to redirect the Lunar efforts to Falcon Heavy?No impact to SLS. Remember, Falcon Heavy hasn't just come on the scene....in fact she's years late and SLS wasn't riding along a competitive path. The only rocket that will be muttering in a disgruntled manner will be Delta IV-Heavy.The Delta IV-Heavy isn't going to lose any missions over this. No more orders are being taken. Vulcan is going directly to a heavy capable configuration.
Quote from: Svetoslav on 02/07/2018 12:34 pmHow do you think the successful flight of Falcon Heavy will impact SLS? Will there be consequences? Will development of the rocket continue as planned, will the status quo will be maintained? Or is there any chance for the Adminstration to redirect the Lunar efforts to Falcon Heavy?No impact to SLS. Remember, Falcon Heavy hasn't just come on the scene....in fact she's years late and SLS wasn't riding along a competitive path. The only rocket that will be muttering in a disgruntled manner will be Delta IV-Heavy.
How do you think the successful flight of Falcon Heavy will impact SLS? Will there be consequences? Will development of the rocket continue as planned, will the status quo will be maintained? Or is there any chance for the Adminstration to redirect the Lunar efforts to Falcon Heavy?
SLS, even the interim, limited Block 1 variant, has more payload capability than Falcon Heavy.
Orion is crew capable.
If you'll indulge my lightly comic touch a moment:If Falcon Heavy flies successfully two more times before years end - with big, real payloads - then the knives could be or should be out for SLS. It would then be a LITERAL 'Emporer Has No Clothes' situation... Or more accurately; the Black Knight from 'Monty Python's Holy Grail', with Elon Musk playing the part of King Arthur and SLS/Boeing playing the part of the Black Knight....
It would be a Kerbal Kludge; but an SLS using 4x Falcon 9 Block 5's as strap on, flyback boosters would have extraordinary capability. Hey, Dr Steve Pietrobon; have at it!
I'm an SLS fan, but I wouldn't mind seeing some of the outer planet probes (e.g. Europa Clipper) moved to Falcon Heavy. After all, if the launcher price in the overall mission budget is much lower, you can devote more $ to the probe itself (no skimming on science instruments). In fact, couldn't low-cost delivery to the outer planets allow even more such probes to be approved?
Quote from: Svetoslav on 02/07/2018 12:34 pmHow do you think the successful flight of Falcon Heavy will impact SLS? Will there be consequences? Will development of the rocket continue as planned, will the status quo will be maintained? Or is there any chance for the Adminstration to redirect the Lunar efforts to Falcon Heavy?ULA offered Atlas V heavy and Atlas Phase 2 would have been even more powerful than Falcon Heavy and it didn't kill Ares which become SLS.Keep in mind FH's LEO payload includes the remaining propellant in the second stage and the limit of the payload adapter is much lower than 63 tons.Now BFS and New Armstrong could render SLS obsolete.
Quote from: bob the martian on 02/07/2018 10:31 pmQuote from: drunyan8315 on 02/07/2018 09:39 pmHow can one discuss the relative merits of two rocket systems without acknowledging that one is throwaway and the other is reusable? The first SLS is going to go up in 4-5 years and then... it will be vaporized. Then you get to build another one.Again, SLS is a creature of politics, not sensibility. It doesn't matter that competing systems are reusable. That's not going to be a factor in deciding whether SLS will continue or not. And to be fair, SLS was bending metal before SpaceX started crashing boosters into the ocean; I'm not going to fault NASA for not pursuing reusability when they were clearly directed to build an expendable system in a relatively short time frame, and especially when their previous reusable system failed to live up to its promises regarding cost and turnaround time. You mean like everyone else in the history of rocketry? ...or was there a difference this time that you so conveniently forgot to mention? Selective amnesia? You people that cling to the impossibly outdated history of how it should be done are impossible to believe.
NASA gave up on reusability because they don't have the chops any more to engineer it. (Hell, they cannot even build an expendable rocket.) You who defend that failure are owners of it.
And how is that 'relatively short time frame' coming along?
Folks, the Emperor is stark naked. Deal.
{snip}SLS/Orion have _worse_ LOC projections than STS did at shutdown. If/when a NASA Administrator or White House grapples with the reality of these figures, it's doubtful crew will launch on SLS/Orion.To the OP's question, SLS/Orion will eventually collapse under their own weight, regardless of FH or any of the other heavy lifters in design/development. Between a poor flight safety projection, an incompetent flight rate, and a cost/budget mismatch that keeps pushing milestones over the horizon, a good NASA Administrator with White House backing can make a credible argument for termination to Congress without ever mentioning FH, especially if they could present a reasonable plan for what to do with the workforce. With the right leadership, NASA does not necessarily have to wait for Senator Shelby to retire to remove the SLS/Orion albatross from around its neck.What FH, NG, VH, and maybe eventually NA and BFR do is alter the conversation about what to do with the SLS/Orion workforce after termination. If there are three providers offering up to five different heavy lift launchers, does NASA (or the USG in general) really need to be in the ETO trucking business anymore? Or should that talent and resources be focused elsewhere?Do you want your cryogenic rocket propulsion engineer at MSFC working on an ETO upper stage or an interplanetary transit stage? Do you want your life support engineer at JSC working on yet another ETO capsule or a planetary surface habitat? Do you want your plasma thermodynamics engineer at ARC or LaRC working on Earth reentry or Mars entry?I think the emergence of FH and its kin is more important to how the NASA human space flight program is organized and focused after SLS/Orion termination than to the termination of SLS/Orion itself.
The SLS will continue development, which would only make sense given that nearly all the flight hardware has been made for EM-1, and flight hardware is already in process for EM-2
Quote from: drunyan8315 on 02/07/2018 09:39 pmHow can one discuss the relative merits of two rocket systems without acknowledging that one is throwaway and the other is reusable? The first SLS is going to go up in 4-5 years and then... it will be vaporized. Then you get to build another one. Because when Falcon Heavy is flown in its partially reusable form (boosters and core recovered), it only gets Atlas 5-53x capability. It is a "heavy lifter" only when it, too, is expended, and even then it falls short of even SLS Block 1. It can't lift Orion beyond low earth orbit in a single launch, so multiple expended Falcon Heavies would be needed. These expendable versions are going to cost substantially more than the numbers everyone sees on the SpaceX web site. That's not to say that Falcon Heavy and other rockets won't be able to play a big role in NASA's deep space program. There should be plenty of opportunities for systems like these. - Ed Kyle
Multiple launches are not a problem because it is so much cheaper than SLS that you could afford five or six for the price of one SLS launch. You also don't need expendable versions, you simple expend a used stage. The trouble is that there isn't much of a role for FH in NASA's current state. How much resupply does a deep space gateway need that only gets one or two flights a year from SLS(not much)? And the only thing official so far I have seen calls for propellant deliveries only!
Quote from: pathfinder_01 on 02/08/2018 07:19 pmMultiple launches are not a problem because it is so much cheaper than SLS that you could afford five or six for the price of one SLS launch. You also don't need expendable versions, you simple expend a used stage. The trouble is that there isn't much of a role for FH in NASA's current state. How much resupply does a deep space gateway need that only gets one or two flights a year from SLS(not much)? And the only thing official so far I have seen calls for propellant deliveries only!The energy required to reach the Moon compared to LEO is so much higher that although the DSG is smaller than the ISS, the heaviest commercial vehicles can only lift modest amounts of payload to lunar orbit. Commercial resupply could potentially be amortized through using the same vehicles to reach the ISS and DSG. The Moon is also different to the ISS because there are more destinations for payloads than the DSG itself, human controllerd rovers, probes and base equipment can be delivered directly to the surface. Satellites for observation, navigation and communications can be positioned in various lunar orbits to support the DSG and surface infrastructure.