Quote from: Svetoslav on 02/12/2018 07:11 pmOK, let's paraphrase the question.Could a rocket (such as SLS) continue its existence if her direct competitors offer cheaper options?Could such a rocket exist and fly, even if it has limited use (i.e. missions to lunar orbit) and no commercial launches?The answer should be a theoretical yes. But could it be, in this specific case? BFR and NA will totally price SLS out of the market. The estimated $1 billion cost per launch of SLS is absolutely insane especially in the light of the BFR announcement last IAC. Cost of BFR per launch will be cheaper than F9 with 1st stage reuse never mind SLS and NA will likely be competitive with BFR on launch cost. Expendable launchers such as SLS won't stand a chance in a few years time as the launch market moves towards reusable systems.
OK, let's paraphrase the question.Could a rocket (such as SLS) continue its existence if her direct competitors offer cheaper options?Could such a rocket exist and fly, even if it has limited use (i.e. missions to lunar orbit) and no commercial launches?The answer should be a theoretical yes. But could it be, in this specific case?
Quote from: DJPledger on 02/12/2018 06:42 pmQuote from: RDoc on 02/12/2018 06:38 pmQuote from: DJPledger on 02/12/2018 06:25 pm1. BFR and NA replace SLS because SLS is so dammed expensive.2. BO designs NA to launch Orion as a payload option so SLS not needed.3. NA may be superior to SLS for TLI.4. SLS can no way compete with BFR and NA forcing it's cancellation.5. Just cancel SLS, give it up as a bad job to stop further money bleeding and hand over funding for BFR and NA dev.6. US of BFR may start testing by the time EM-1 launches.So all in all SLS needs to be cancelled now to stop billions more $ being wasted.Unfortunately, SLS is doing precisely what it was intended to do. Spread lots of pork around to lobbyists and constituents. It's not called the Senate Launch System for nothing, and as long as the money keeps flowing, the project will continue, launch or not.Perhaps Musk and Bezos should get together and force NASA to cancel SLS and to fund their HLV systems.They couldn't do any such thing, even if they tried to do what you propose. A. NASA is not in charge of deciding how its budget is spent, Congress is; and B. that's not how federal funding works. If Congress cancels a project, that money isn't redistributed, it's just gone.
Quote from: RDoc on 02/12/2018 06:38 pmQuote from: DJPledger on 02/12/2018 06:25 pm1. BFR and NA replace SLS because SLS is so dammed expensive.2. BO designs NA to launch Orion as a payload option so SLS not needed.3. NA may be superior to SLS for TLI.4. SLS can no way compete with BFR and NA forcing it's cancellation.5. Just cancel SLS, give it up as a bad job to stop further money bleeding and hand over funding for BFR and NA dev.6. US of BFR may start testing by the time EM-1 launches.So all in all SLS needs to be cancelled now to stop billions more $ being wasted.Unfortunately, SLS is doing precisely what it was intended to do. Spread lots of pork around to lobbyists and constituents. It's not called the Senate Launch System for nothing, and as long as the money keeps flowing, the project will continue, launch or not.Perhaps Musk and Bezos should get together and force NASA to cancel SLS and to fund their HLV systems.
Quote from: DJPledger on 02/12/2018 06:25 pm1. BFR and NA replace SLS because SLS is so dammed expensive.2. BO designs NA to launch Orion as a payload option so SLS not needed.3. NA may be superior to SLS for TLI.4. SLS can no way compete with BFR and NA forcing it's cancellation.5. Just cancel SLS, give it up as a bad job to stop further money bleeding and hand over funding for BFR and NA dev.6. US of BFR may start testing by the time EM-1 launches.So all in all SLS needs to be cancelled now to stop billions more $ being wasted.Unfortunately, SLS is doing precisely what it was intended to do. Spread lots of pork around to lobbyists and constituents. It's not called the Senate Launch System for nothing, and as long as the money keeps flowing, the project will continue, launch or not.
1. BFR and NA replace SLS because SLS is so dammed expensive.2. BO designs NA to launch Orion as a payload option so SLS not needed.3. NA may be superior to SLS for TLI.4. SLS can no way compete with BFR and NA forcing it's cancellation.5. Just cancel SLS, give it up as a bad job to stop further money bleeding and hand over funding for BFR and NA dev.6. US of BFR may start testing by the time EM-1 launches.So all in all SLS needs to be cancelled now to stop billions more $ being wasted.
Quote from: DJPledger on 02/12/2018 07:20 pmQuote from: Svetoslav on 02/12/2018 07:11 pmOK, let's paraphrase the question.Could a rocket (such as SLS) continue its existence if her direct competitors offer cheaper options?Could such a rocket exist and fly, even if it has limited use (i.e. missions to lunar orbit) and no commercial launches?The answer should be a theoretical yes. But could it be, in this specific case? BFR and NA will totally price SLS out of the market. The estimated $1 billion cost per launch of SLS is absolutely insane especially in the light of the BFR announcement last IAC. Cost of BFR per launch will be cheaper than F9 with 1st stage reuse never mind SLS and NA will likely be competitive with BFR on launch cost. Expendable launchers such as SLS won't stand a chance in a few years time as the launch market moves towards reusable systems.No, they won't. SLS will fly its first mission before BFR and NA become operational. As such, NASA won't be forced to use commercial alternatives.SLS will be primarily used to fly government missions. As such, SLS is not competing with BFR and NA.The primary markets for BFR and NA are commercial missions, not government work.IMO, the fate of SLS after the debut of Falcon Heavy is that it will continue to exist and (eventually) launch, even after BFR and NA have arrived on the scene.
If SLS gets cancelled now that will be end of DSG and NASA HSF BLEO. The freed up money will go back into Government coffers. NASA may buy commercial HSF services to BLEO but it won't pay for development. SLS Orion and DSG enables HSF to BLEO. Commercial companies will eventually follow and do it cheaper allowing SLS to be cancelled.
Quote from: Proponent on 02/10/2018 02:15 pmQuote from: A_M_Swallow on 02/10/2018 05:54 amQuote from: Robotbeat on 02/10/2018 03:52 amDon't go into *Low* lunar orbit but instead an elliptical orbit. Way less delta-V to enter and leave. Solves a whole bunch of problems and makes logistics by a whole range of rockets easier.Does an elliptical orbit result in spacecraft having to use instantaneous launches due to tiny windows?I don't think the windows are excessively short. The problem I see is that an efficient TEI burn must take place at perilune and on the far side of the moon. So it seems to me that an elliptical orbit leaves you with departure windows only once a month. You could move perilune, but that takes delta-V. Am I missing something?Isn't it one launch window (from Low Earth Orbit) per lunar orbit of the lunar gateway/orbiter. That doesn;t impose a constraint on launch from Earth, assuming the upper stage can orbit for between 0 and a few days.
Quote from: A_M_Swallow on 02/10/2018 05:54 amQuote from: Robotbeat on 02/10/2018 03:52 amDon't go into *Low* lunar orbit but instead an elliptical orbit. Way less delta-V to enter and leave. Solves a whole bunch of problems and makes logistics by a whole range of rockets easier.Does an elliptical orbit result in spacecraft having to use instantaneous launches due to tiny windows?I don't think the windows are excessively short. The problem I see is that an efficient TEI burn must take place at perilune and on the far side of the moon. So it seems to me that an elliptical orbit leaves you with departure windows only once a month. You could move perilune, but that takes delta-V. Am I missing something?
Quote from: Robotbeat on 02/10/2018 03:52 amDon't go into *Low* lunar orbit but instead an elliptical orbit. Way less delta-V to enter and leave. Solves a whole bunch of problems and makes logistics by a whole range of rockets easier.Does an elliptical orbit result in spacecraft having to use instantaneous launches due to tiny windows?
Don't go into *Low* lunar orbit but instead an elliptical orbit. Way less delta-V to enter and leave. Solves a whole bunch of problems and makes logistics by a whole range of rockets easier.
Quote from: TrevorMonty on 02/13/2018 09:05 amIf SLS gets cancelled now that will be end of DSG and NASA HSF BLEO. The freed up money will go back into Government coffers. NASA may buy commercial HSF services to BLEO but it won't pay for development. SLS Orion and DSG enables HSF to BLEO. Commercial companies will eventually follow and do it cheaper allowing SLS to be cancelled. Cancelling SLS now will only delay DSG and NASA HSF BLEO until BFR IOC then be joined by NA a few years later. Gov. should just give the money freed up by SLS cancellation to SpaceX and BO for BFR and NA dev. respectively. Better to delay NASA BLEO HSF a few years by cancelling SLS for the dramatically reduced costs benefits of using BFR and NA. Need to force NASA to pay for commercial HLV dev. using the money saved from SLS cancellation.Perhaps we should all get together and lobby Congress and NASA to get SLS cancelled ASAP and to divert funds towards expediting BFR and NA dev.
If SLS gets cancelled now that will be end of DSG and NASA HSF BLEO. The freed up money will go back into Government coffers. NASA may buy commercial HSF services to BLEO but it won't pay for development. SLS Orion and DSG enables HSF to BLEO.
Perhaps we should all get together and lobby Congress and NASA to get SLS cancelled ASAP and to divert funds towards expediting BFR and NA dev.
A very interesting article on the Space Review:""""SLS is simply one more government project, liberally marinated in absurdity, that continues because it has, thus far, flown below the public’s radar. Absent public outrage or, even worse, public ridicule, many such projects have soldiered on in obscurity for long periods based entirely on the politics of parochial self-interest and mutual back-scratching. But no amount of political influence tends to be able to save these things when the general public takes note. Especially when they laugh.""""http://thespacereview.com/article/3429/1
Quote from: DJPledger on 02/13/2018 09:19 amPerhaps we should all get together and lobby Congress and NASA to get SLS cancelled ASAP and to divert funds towards expediting BFR and NA dev.No, they don't need the money
OK, let's paraphrase the question.Could a rocket (such as SLS) continue its existence if her direct competitors offer cheaper options?
Quote from: Svetoslav on 02/12/2018 07:11 pmOK, let's paraphrase the question.Could a rocket (such as SLS) continue its existence if her direct competitors offer cheaper options?Everyone keeps missing the point.SLS is not subject to any kind of market pressure. At all. The eventual existence of multiple commercial offerings with equivalent performance for less cost is completely, absolutely irrelevant to SLS' future. Cost effectiveness is not the metric against which SLS' continued survival will be measured. Keeping federal dollars flowing into specific districts is the metric against which its survival is measured. As long as it fills that role, arguments about cost per launch, rate of launches, lack of missions, etc., will have little weight. Politics and nothing else will decide SLS' fate. Certain elected officials will have to retire, die, or lose elections in order for SLS to be cancelled irrespective of the existence (or not) of FH, BFR, NA, etc. Sure, we can argue to our elected representatives that it's a waste of money and should be cancelled, and most of them will agree and push for cancellation, but unless they're in the right positions of power, it won't happen.
Quote from: Jim on 02/13/2018 01:21 pmQuote from: DJPledger on 02/13/2018 09:19 amPerhaps we should all get together and lobby Congress and NASA to get SLS cancelled ASAP and to divert funds towards expediting BFR and NA dev.No, they don't need the moneyAgreed.And if we do find them (indirectly), the govt should bargain hard and make them work hard for every dollar through competition.
Spaceflightnow.com:"NASA officials said there would be significant roles for commercial partners in the lunar exploration plan. In 2022, a power and propulsion module could be launched aboard a commercial rocket to begin the construction of a space station named the Lunar Orbital Platform – Gateway. Employing solar-electric propulsion with plasma engines, the module was previously slated to launch on the NASA-owned Space Launch System"Interesting report on today's Spaceflightnow.com based on just-released NASA budget outline. According to the report, NASA could launch the Power/Prop module of the Deep Space Gateway aboard a COMMERCIAL rocket in 2022 (instead of SLS). Commercial rockets with the lift capacity in 2022: Falcon Heavy or perhaps New Glenn.