I really suspect that SpaceX will be doing just BFR development over the next decade while the actual vehicle to mars will continue to be studied and refined without a firm mission architecture until they actually have to cross that bridge.
Quote from: guckyfan on 10/20/2015 08:15 pmThings do change and I can't wait for the great reveal. I like MCT going all the way and back for a simple reason, not only because Elon Musk said so. It is operationally simple, straightforward and elegant. Making MCT ready for the next flight is a lot simpler down on earth than in space. Getting the weight back up into orbit is not an expensive problem given the capability of BFR.I agree, with a proviso:As you add more and more little things to make it work, a straightforward plan can have terrible complexities. Many refueling dockings, transferring people from several Dragons to the MCT, etc... there will be a point where making an easy system work isn't easy. But otherwise yes... if they can make it work in the simple way envisaged it will make the trip cheaper (which is ultimately the SpaceX goal). And 20 Synods later they'll have a different vision for higher numbers.
Things do change and I can't wait for the great reveal. I like MCT going all the way and back for a simple reason, not only because Elon Musk said so. It is operationally simple, straightforward and elegant. Making MCT ready for the next flight is a lot simpler down on earth than in space. Getting the weight back up into orbit is not an expensive problem given the capability of BFR.
Quote from: Impaler on 10/21/2015 02:37 amHas anyone considered the possibility that the upcoming reveal will just be the Rocket, aka BFR, and not in fact the whole system? I really suspect that SpaceX will be doing just BFR development over the next decade while the actual vehicle to mars will continue to be studied and refined without a firm mission architecture until they actually have to cross that bridge.That is precisely my thinking.The BFR is congruent with SX's core competency and is a necessary precursor. Even it will undergo changes after hopefully SX succeeds in recovering and re-flying F9 cores. I think Musk will speak to the MCT issue, but still in vague terms. Even were he somewhat specific I don't think many observers here would expect the details to hold true during what I expect would be a longer than a decade gestation for the Block One MCT, which I expect to be quite different from its folllow-on.There are too many outside SX technology developments ongoing* to fixate and spend R&D $ on a MCT in this decade, and probably for the early part of the next.*SEP panels & engines, plasma propulsion, magneto aero capture, life support systems tech, etc. Never mind extreme wildcards like one of the myriad small fusion projects actually working.
Has anyone considered the possibility that the upcoming reveal will just be the Rocket, aka BFR, and not in fact the whole system? I really suspect that SpaceX will be doing just BFR development over the next decade while the actual vehicle to mars will continue to be studied and refined without a firm mission architecture until they actually have to cross that bridge.
Quote from: Impaler on 10/21/2015 02:37 amHas anyone considered the possibility that the upcoming reveal will just be the Rocket, aka BFR, and not in fact the whole system? I really suspect that SpaceX will be doing just BFR development over the next decade while the actual vehicle to mars will continue to be studied and refined without a firm mission architecture until they actually have to cross that bridge.That is precisely my thinking.The BFR is congruent with SX's core competency and is a necessary precursor. ...
...There are too many outside SX technology developments ongoing* to fixate and spend R&D $ on a MCT in this decade, and probably for the early part of the next.*SEP panels & engines, plasma propulsion, magneto aero capture, life support systems tech, etc. Never mind extreme wildcards like one of the myriad small fusion projects actually working.
Quote from: philw1776 on 10/21/2015 01:23 pmQuote from: Impaler on 10/21/2015 02:37 amHas anyone considered the possibility that the upcoming reveal will just be the Rocket, aka BFR, and not in fact the whole system? I really suspect that SpaceX will be doing just BFR development over the next decade while the actual vehicle to mars will continue to be studied and refined without a firm mission architecture until they actually have to cross that bridge.That is precisely my thinking.The BFR is congruent with SX's core competency and is a necessary precursor. Even it will undergo changes after hopefully SX succeeds in recovering and re-flying F9 cores. I think Musk will speak to the MCT issue, but still in vague terms. Even were he somewhat specific I don't think many observers here would expect the details to hold true during what I expect would be a longer than a decade gestation for the Block One MCT, which I expect to be quite different from its folllow-on.There are too many outside SX technology developments ongoing* to fixate and spend R&D $ on a MCT in this decade, and probably for the early part of the next.*SEP panels & engines, plasma propulsion, magneto aero capture, life support systems tech, etc. Never mind extreme wildcards like one of the myriad small fusion projects actually working.I sure we will get some nice video of a giant rocket taking off. It might just have some totally ambiguous payload-fairing on it leaving everything beyond the launch unspecified much the way Vulcan was introduced, this would be a clear sign that they are shopping BFR around to commercial customers, but even I would find that a bit conservative given the hype that has been built up.More likely were shown some kind of large mars vehicle reaching LEO on top of the BFR. But then the video might just cut to said vehicle landing on mars with all the details of refueling, trajectory, aerocapture, entry etc etc left out. Or on the opposite end of the spectrum we could see a nearly full 'architecture' which covers all these steps and Musk will be open with the numbers.But even the most minimal video will give some ideas as to what the present preferred architecture is and one of the three camps of 'Super Dragon', 'Integrated Bi-conic' and 'Separate Bi-conic' will likely get to crow, despite the fact that the shown architecture is still in flux, given the kind of 'Holy writ' that people ascribe to offhand statements of Musk their will be no point arguing with a video. The speculation would then narrow down to other operational details of how the vehicle actually dose the mission and what the ultimate cost will be, how fast if at all SpaceX can put the vehicle into service, if SLS is doomed and when first landing on mars might happen.
Quote from: GregA on 10/21/2015 08:18 pmYes EM's said it. I think it was something like "you need a really big f'ing rocket, a BFR". But if that memory is correct, then he wasn't really calling it a BFR at the time... just describing it. If that was the only mention of it, then the context still doesn't seem to indicate differentiation between a launch vehicle and a spacecraft f he was saying to land 100mt on Mars, you need a really big f'ing rocket...for example...there's nothing in that to indicate a stand alone rocket, and a separate spacecraft. I'm more saying, was there a reference to "BFR" and "MCT" being referred to separately in the same comment, like how "Dragon" and "Falcon" are referred to differently in the same comment. If so, then there could be a reasonable chance EM will just be announcing the LV. Although even then, it's main purpose would be to loft MCT to space, just like the main purpose of the Saturn V was to loft the Apollo CSM and LEM through TLI. The spacecraft were in the "unveilings" from the beginning. Even when it was originally Direct Ascent instead of LOR. So I would expect something like that for this unveiling. At least a working concept for the spacecraft, even if there is a stand alone LV.But good to know that EM actually did use the term. I'd not been aware of that. :-)
Yes EM's said it. I think it was something like "you need a really big f'ing rocket, a BFR". But if that memory is correct, then he wasn't really calling it a BFR at the time... just describing it.
This might be useful Lobo[Question about getting to Mars.] I don't think the Moon is a necessary step, but I think if you've got a rocket and spacecraft capable of going to Mars, you might as well go to the Moon as well - it's along the way. That's like crossing the English Channel, relative to Mars. So, it's like, if you have these ships that could cross the Atlantic, would you cross the English Channel? Probably. It's definitely not necessary, but you'd probably end up having a Moon base just because, like, why not, ya know. It terms of the key technologies, obviously it would be great to have some sort of fundamental new thing that's never existed before and pushes the boundaries of physics, that'd be great, but as far as the physics that we know today, I actually think we've got the basic ingredients - they're there. I mean, if you do a densified liquid methalox rocket with on-orbit refueling, so like you load the spacecraft into orbit and then you send a whole bunch of refueling missions to fill up the tanks and you have the Mars colonial fleet - essentially - that gets built up during the time between Earth-Mars synchronizations, which occur every 26 months, then the fleet all departs at the optimal transfer point. I think we have - we don't need any sort of thing that people don't already know about, I believe. I believe we've got the building blocks, but the mass efficiency is extremely important. So, having better heat shields, that obviously are reusable.http://shitelonsays.com/transcript/elon-musk-at-mits-aeroastro-centennial-part-2-of-6-2014-10-24and this from 2005:In past talks Musk has hinted at the development of something called the “BFR” (where B stands for “big” and R for “rocket”), a heavy-lift vehicle far larger than the Falcon family of vehicles. At SpaceVision2005 Musk disclosed that the BFR, in its current iteration, would use “multiple” Merlin 2 engines. The BFR would be able to place 100 tons in low Earth orbit, putting it in competition with NASA’s planned shuttle-derived heavy-lift launcher. The BFR is so big, Musk said, that it’s too large for the BFTS at their Texas test site...http://www.thespacereview.com/article/497/1
Lobo is on the right track here. Before jumping to design solutions, we need to find the requirements for BFR and MCT first. Thats like engineering 101. That hasn't been happening to the extend needed to define an MCT or BFR. Lobo just started that process and I am very glad he did it.
Quote from: Semmel on 10/22/2015 10:45 amLobo is on the right track here. Before jumping to design solutions, we need to find the requirements for BFR and MCT first. Thats like engineering 101. That hasn't been happening to the extend needed to define an MCT or BFR. Lobo just started that process and I am very glad he did it.Agree that's necessary - but I believe he and a few others with the appropriate knowledge have been getting into those requirements for quite some time - and from that trying to ascertain what could work that still fits within what EM has said.(Or did I miss some new approach?)
Sleeping your way to mars.http://www.parabolicarc.com/2015/10/23/snooze-mars/
Musk has worked out just enough about potential "MCT" approaches that he has a generic requirement for his BFR launcher. I am certain that he has explored the solution space for Mars transport and wants a launch capability that can support solutions from all chemical solution to SEP/chemical hybrid transport and other possible more exotic solutions. Technology over a >10 year timeframe does not stay still. The 1st and 2nd stage need only be able to get the 100mT cargo plus MCT dry weight into appropriate LEO. If all his broad brush Mars transport solution space fits within these parameters and their evolutionary improvements (e.g.Merlin to Merlin FT), he's good to go.
... So, the Block One MCT will likely again be different from the MCT that lands the first crew on Mars June 2033 following the un-crewed MCT bringing the ISRU equipment May 2031.
Quote from: philw1776 on 10/23/2015 02:13 pmMusk has worked out just enough about potential "MCT" approaches that he has a generic requirement for his BFR launcher. I am certain that he has explored the solution space for Mars transport and wants a launch capability that can support solutions from all chemical solution to SEP/chemical hybrid transport and other possible more exotic solutions. Technology over a >10 year timeframe does not stay still. The 1st and 2nd stage need only be able to get the 100mT cargo plus MCT dry weight into appropriate LEO. If all his broad brush Mars transport solution space fits within these parameters and their evolutionary improvements (e.g.Merlin to Merlin FT), he's good to go.But why build BFR first? BFR has the most infrastructure requirements. Additionally, you're making the implicit assumption that MCT isn't essentially BFR's second stage. I really, REALLY don't expect SpaceX to make the same mistake NASA is currently making by building a super-expensive-to-develop-and-maintain launch vehicle without really anything to launch.philw1776: No, I see the MCT as the BFR stage 2. Just its specifics beyond engines & tankage at TBD. I see several cargo refueler MCTs as does Musk to fuel up the transit MCT.Quote... So, the Block One MCT will likely again be different from the MCT that lands the first crew on Mars June 2033 following the un-crewed MCT bringing the ISRU equipment May 2031.I have no doubt MCT will evolve, but your timeline is not the same as SpaceX's timeline. They expect crewed missions much earlier. Which makes sense, as it doesn't make sense to develop a capability and then essentially just let it languish, sucking up money while nothing is accomplished (another mistake NASA is making, though this is mostly Congress's fault).