Author Topic: MCT Speculation and Discussion Thread 4  (Read 572983 times)

Offline JamesH

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Re: MCT Speculation and Discussion Thread 4
« Reply #860 on: 10/20/2015 07:34 PM »
Presumably they will use something that can withstand a year in transit (I'm thinking micrometeorite impacts) then still be usable for a shield. Which is best suited, PicaX or metallic?

Offline JamesH

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Re: MCT Speculation and Discussion Thread 4
« Reply #861 on: 10/20/2015 07:36 PM »
why is MCT always considered a single vehicle launched from Earth? Has Musk in any way indicated that?

isn´t there any possibility MCT could be a space only craft in permanent transit between Mars and Earth, picking people on Earth and dropping them on Mars?

that way, MCT could be faster and bigger. Because you wouldn´t need to accelerate an habitat for 100 people to live for 6 months (or less if possible) EVERY trip.

Just accelerate (to catch up with MCT and transfer people) a "small" capsule where you have 100 people crammed in a tight space with their luggage.


The idea of a big transport to Mars for people to live in for 6 months being launched EVERY trip sounds to me somewhat like launching half the space station into space every time a new astronaut goes to it.

Not, always, I'm one of a few voices in the wilderness that still see semi-direct like architectures as most likely and fully compatible with Musk's goals and statements so far.  And we should NOT be taking even clear statements of intent as evidence that alternatives have been taken off the table as their are FAR too many instances of early statements of intent in the engineering minutia by SpaceX that fall through.
I'm wilderness bound. MUsk's statement was a while ago, and things definitely change. I think its going to be a lot more radical than people have been speculating so far.

Online guckyfan

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Re: MCT Speculation and Discussion Thread 4
« Reply #862 on: 10/20/2015 08:15 PM »
I'm wilderness bound. MUsk's statement was a while ago, and things definitely change. I think its going to be a lot more radical than people have been speculating so far.

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.

Offline GregA

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Re: MCT Speculation and Discussion Thread 4
« Reply #863 on: 10/20/2015 08:54 PM »
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.

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.

Offline Robotbeat

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Re: MCT Speculation and Discussion Thread 4
« Reply #864 on: 10/20/2015 11:50 PM »
Sorry it took me a while to respond. I apologize in advance for my abrasive tone, but I'm a little annoyed at the lack of an attempt to understand what I wrote and instead go with an obviously absurd interpretation (at least for the first part).

...


That was also true for each and every Shuttle and Apollo reentry. The reentry corridor was narrow. But if one MCT out of 500 ships did skip out on a heliocentric trajectory, you'd just have to devote one or two stripped-down MCTs in orbit or on the surface of Mars to be ready to mount a rescue mission (or wouldn't even have to be devoted to that purpose, just ready to be fueled up when the MCTs are arriving). In the grand scheme of things, that would be fairly cheap insurance.

No, Shuttle did not do Aerocapture because it was not going anywhere near escape velocity on atmospheric entry and could not leave the Earth if it over-shot
Thank you Captain Obvious.
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it did controlled skips and banked turns along the atmosphere to dissipate energy but that is not the same as aerocapture.
Nope, but the reentry corridor is quite narrow in order to keep the reusable and fragile TPS intact, which was my point: narrow reentry corridor.
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When you under-shoot aerocapture you end up back on a Heliocentric orbit leaving the planet entirely.
Of course. If you screw up the Shuttle reentry corridor, you don't just end up on a heliocentric orbit, you end up completely dead. I'd rather be on a heliocentric trajectory, waiting on a rescue mission, than completely dead. But the narrow reentry corridor didn't kill anyone on either Shuttle or Apollo, and we have more sophisticated guidance and navigation than we did then.

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The rescue idea is ridiculous, the lost vehicle would be heading for a aphelion well into the asteroid belt and even if another MCT on mars had the DeltaV to rendezvous with it they would have not have the DeltaV to return to mars or likely any other planet on a time scale of less then years.
Um, yes it would. A stripped down MCT in elliptical Mars orbit could have capability for FAR more C3 than the MCT that didn't quite aerocapture enough. It could launch almost immediately after the failed aerocapture, easily catching up to the MCT in question. You aren't stuck waiting for orbits to come back around because you would have plenty of delta-v to work with. On the scale that SpaceX is dealing with, this sort of capability would be cheap. It's not "ridiculous" if this is the only reason keeping you from attempting aerocapture.

Additionally, the MCT that missed the full aerocapture still has 0.5-1km/s of propellant on board for landing that it could use (while still deep in Mars' gravity well, so getting an Oberth Multiplier of up to 4) to put itself into an elliptical orbit if it only undershot the aerocapture a little bit. So you would have to be REALLY far off (not just slightly off) in order to be automatically on a heliocentric trajectory. Even during a regular, low-speed entry, being significantly off can easily kill you, so it's something you'll have to get pretty good at regardless of whether or not you do aerocapture.

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No, it's also useful during aerocapture because you can adjust for uncertainties in the atmosphere's density. And you can utilize negative lift to give you more time-in-atmosphere.

Yes this is correct, the more lift you can generate the wider your aerocapture corridor is and the more adjustment can be made in real time due to atmospheric conditions.  It is an argument in favor of the bi-conic shape when doing aerocapture.
Sure, but even a typical capsule shape can generate significant lift. And with greater entry precision, that amount of lift may be all you really need (more later).
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100 day transfers don't just involve high amounts of velocity to dissipate, more and more of that velocity has to be dissipated on the first pass.
Sure. But not more than needs to be dissipated for lunar reentry.

Apollo entry was at 10.77 km/s, contrary to popular belief they could not skip off the atmosphere and be lost in space forever, they would simply have re-entered later after a large elliptical orbit during which they would run out of oxygen because they were below escape velocity.

Burnate already did the numbers, on the 102 day transit your perigee at mars is 9.17 km/s and you need to shed 4.7 km/s.  That's about half your velocity, and about 50% of the energy of the Apollo return.

The 100 day transit is even worse (it saves Earth Escape DeltaV by raising velocity at mars), cause your velocity is 13.77 km/s of which you must shed 9.2 km/s, which is 88% of your total energy.  In fact you need to shed more energy then the entire Apollo lunar return, about 60% more.
I pretty clearly was talking about velocity difference (i.e. acceleration times time), not energy.

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I'm very skeptical that the cord through the martian atmosphere can be long enough to provide this much deceleration within even your g limits.  The faster your going to less time you spend in the atmosphere and your deceleration force needs to increase exponentially.   And as entry velocities increase the corridor gets narrower and narrower, according to http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19930003532.pdf even with 5 g limit the entry velocity had to kept to under 9 km/s to keep the corridor to 1 degree wide with a 0.3 L/D vehicle like a capsule.
So we'll have to get within less than a degree wide. I don't see the problem; we're much better at Mars entry precision than we were when that document was written (1992), particularly with the Curiosity rover's entry, and clearly some sort of areospatial positioning system could be deployed to enhance the precision to within a tiny fraction of a degree (on Earth, you can get within centimeters). But even with purely optical aids, you can do much better than a single degree: "Other investigators have shown that with the use of onboard optical sightings of the Martian moons, the error in the atmospheric entry angle could be reduced to +/-0.25 degrees without the need for secondary spacecraft to serve as navigational aides (Ref. 45)." (In fact, we already have spacecraft around Mars that could be used for this purpose.)
« Last Edit: 10/21/2015 12:10 AM by Robotbeat »
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Offline Lars-J

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Re: MCT Speculation and Discussion Thread 4
« Reply #865 on: 10/21/2015 12:03 AM »
why is MCT always considered a single vehicle launched from Earth? Has Musk in any way indicated that?

isn´t there any possibility MCT could be a space only craft in permanent transit between Mars and Earth, picking people on Earth and dropping them on Mars?

that way, MCT could be faster and bigger. Because you wouldn´t need to accelerate an habitat for 100 people to live for 6 months (or less if possible) EVERY trip.

Just accelerate (to catch up with MCT and transfer people) a "small" capsule where you have 100 people crammed in a tight space with their luggage.


The idea of a big transport to Mars for people to live in for 6 months being launched EVERY trip sounds to me somewhat like launching half the space station into space every time a new astronaut goes to it.

Because cyclers are inherently a ... dumb idea. IMO. You've got to accelerate all the crew, crew consumables, cargo, and propellant for the lander to a Mars transfer orbit anyway. Just to catch up to the cycler. All while stuck in VERY cramped conditions. This has some very serious failure modes - what if you cannot rendezvous with the cycler?

Do the math, look at the size of the "capsule" you need to transport all that to the cycler, and you'll realize that your small transfer vessel is almost at the size you need for normal transit, so you might as well just scale up the crew area and skip the cycler altogether. (And that larger crew area will be needed on Mars as well)

And that doesn't even beging to deal with the limited and few launch windows a cycler offers. And how you deal with a fleet of ships going in the same launch window.

No, I maintain that "cyclers" make no sense. And I'm dumbfounded why otherwise brilliant people such as Aldrin keep advocating for them.
« Last Edit: 10/21/2015 12:04 AM by Lars-J »

Offline Space Ghost 1962

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Re: MCT Speculation and Discussion Thread 4
« Reply #866 on: 10/21/2015 12:59 AM »
why is MCT always considered a single vehicle launched from Earth? Has Musk in any way indicated that?

isn´t there any possibility MCT could be a space only craft in permanent transit between Mars and Earth, picking people on Earth and dropping them on Mars?

that way, MCT could be faster and bigger. Because you wouldn´t need to accelerate an habitat for 100 people to live for 6 months (or less if possible) EVERY trip.

Just accelerate (to catch up with MCT and transfer people) a "small" capsule where you have 100 people crammed in a tight space with their luggage.


The idea of a big transport to Mars for people to live in for 6 months being launched EVERY trip sounds to me somewhat like launching half the space station into space every time a new astronaut goes to it.

Because cyclers are inherently a ... dumb idea. IMO. You've got to accelerate all the crew, crew consumables, cargo, and propellant for the lander to a Mars transfer orbit anyway. Just to catch up to the cycler. All while stuck in VERY cramped conditions. This has some very serious failure modes - what if you cannot rendezvous with the cycler?

Do the math, look at the size of the "capsule" you need to transport all that to the cycler, and you'll realize that your small transfer vessel is almost at the size you need for normal transit, so you might as well just scale up the crew area and skip the cycler altogether. (And that larger crew area will be needed on Mars as well)

And that doesn't even beging to deal with the limited and few launch windows a cycler offers. And how you deal with a fleet of ships going in the same launch window.

No, I maintain that "cyclers" make no sense. And I'm dumbfounded why otherwise brilliant people such as Aldrin keep advocating for them.
Google "The MCV: A Mars Colonization Vehicle". Two kids at the Mars Society (Musk was there too!). Slightly different concept, but enough like Aldrin's cycler in ways that he was verbally jousting with them.

They were doing accelerated orbits with both Mars and Earth assists for high velocity exchanges of small craft carrying scalable numbers of crew mostly.

To a captured and repurposed asteriod. They got the idea from Rusty Schwieckart and Robert Farquhar - the orbital mechanics is of a chaotic orbit with chosen encounters. Using asteroid deflection to drive asteroids to accurate closest possible encounters as a means of high velocity propulsion.

They were after the GCR radiation protection of the asteroid, and the ability to accumulate resources successively, with ISRU and food cultivation reducing the need for supply mass. A later version added the ability to use SEP in the relaxation period of the chaotic orbit (when unusable for transport given Earth Mars orientation) for high mass additions, where a low velocity encounter on a long period orbit occurs.

So yes, a related concept does work, but it solves the dilemmas differently then Aldrin's cycler. Oh, and the safety for a missed rendezvous is to bleed off delta-v with a close pass to Earth or Mars, recapturing the small transfer craft. The supplies needed are an issue for initial capture and orbital insertion/management, but in operation only a few days consumables (for safety) beyond transfer needs are used. Rendezvous is well before encounters.

Offline Impaler

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Re: MCT Speculation and Discussion Thread 4
« Reply #867 on: 10/21/2015 02:37 AM »
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.

Offline oiorionsbelt

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Re: MCT Speculation and Discussion Thread 4
« Reply #868 on: 10/21/2015 02:53 AM »
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.
Possibly but it's also possible that reusable second stage and Mars ambitions combine to make BFR/MCT the next step.
 SpaceX has always been a builder of spacecraft as well as a builder of launch vehicles.

Offline The Amazing Catstronaut

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Re: MCT Speculation and Discussion Thread 4
« Reply #869 on: 10/21/2015 03:06 AM »

 SpaceX has always been a builder of spacecraft as well as a builder of launch vehicles.

That's true. We knew about F9 and Dragon pretty much at the same time when both were in development. Actually, didn't dragon development start before F9 did?

I don't imagine this will be prescient. BFR will either come at the same time as the MTC or slightly before. One prescient I do believe in: there won't be a BFR Falcon V analogue, they'll go full monty, and just iteratively upgrade the full size rocket/space craft over time like they're oft to do with F9.
« Last Edit: 10/21/2015 03:08 AM by The Amazing Catstronaut »
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Offline oiorionsbelt

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Re: MCT Speculation and Discussion Thread 4
« Reply #870 on: 10/21/2015 03:14 AM »

 SpaceX has always been a builder of spacecraft as well as a builder of launch vehicles.

That's true. We knew about F9 and Dragon pretty much at the same time when both were in development. Actually, didn't dragon development start before F9 did?

I don't imagine this will be prescient. BFR will either come at the same time as the MTC or slightly before. One prescient I do believe in: there won't be a BFR Falcon V analogue, they'll go full monty, and just iteratively upgrade the full size rocket/space craft over time like they're oft to do with F9.
I have a hard time picturing a payload other than MCT for the first BFR test flight.
Especially if the the MCT is the second stage.
« Last Edit: 10/21/2015 03:15 AM by oiorionsbelt »

Offline nadreck

Re: MCT Speculation and Discussion Thread 4
« Reply #871 on: 10/21/2015 03:25 AM »
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.

No the clues from several sources (like Peter Nasa's post earlier today) suggest that there will be a planned sequence of steps presented that include definite plans with several Mars activities, a more intricate timeline,  further refined definition of the systems that will be used, and finally more clarity on some of the resources being brought to bear to pay for it all.
It is all well and good to quote those things that made it past your confirmation bias that other people wrote, but this is a discussion board damnit! Let us know what you think! And why!

Offline sghill

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Re: MCT Speculation and Discussion Thread 4
« Reply #872 on: 10/21/2015 01:18 PM »
I think the announcement of a SpaceX teaming agreement/partnership/knowledge sharing agreement/ stock swap with a submarine manufacturer will be the trigger that SpaceX is moving forward in earnest with designing the MCT and associated surface pieces. 

General Dynamics would be the natural partner.  A partnership arrangement gets GD back into launching rockets (it's been out of the launcher business since 1998 and the satellite business since 2010).  For SpaceX, it gets large, mobile, long-duration, and potentially nuclear-powered,  habitat systems design and engineering capabilities into their hands. 

It also gets one of the "big three" U.S. defense contractors on its team- something that shouldn't be ignored long term for SpaceX.
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Online philw1776

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Re: MCT Speculation and Discussion Thread 4
« Reply #873 on: 10/21/2015 01:23 PM »
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.

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.
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Online Lobo

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Re: MCT Speculation and Discussion Thread 4
« Reply #874 on: 10/21/2015 07:01 PM »

Because cyclers are inherently a ... dumb idea. IMO. You've got to accelerate all the crew, crew consumables, cargo, and propellant for the lander to a Mars transfer orbit anyway. Just to catch up to the cycler. All while stuck in VERY cramped conditions. This has some very serious failure modes - what if you cannot rendezvous with the cycler?

Do the math, look at the size of the "capsule" you need to transport all that to the cycler, and you'll realize that your small transfer vessel is almost at the size you need for normal transit, so you might as well just scale up the crew area and skip the cycler altogether. (And that larger crew area will be needed on Mars as well)

And that doesn't even beging to deal with the limited and few launch windows a cycler offers. And how you deal with a fleet of ships going in the same launch window.

No, I maintain that "cyclers" make no sense. And I'm dumbfounded why otherwise brilliant people such as Aldrin keep advocating for them.

Yea I think they are ideas that seem better in theory than in practice...for reasons you mention.

They make a little more sense for expensive expendable systems where you perhaps aren't refueling on Mars and every gram is important....like Apollo (and several Mars mission concepts).  So if you can shed a little bit of mass by not having to loft the hab, then there can be advantage.

But, if we are assuming here fully reusable components, with on-surface fueling and a LEO depot that will be cheap [relatively] to launch cheap propellant to...then even gram isn't so precious.  You can sacrifice some mass efficiency for economic efficiency or for additional simplicity/safety.  And just launch one more tanker to the depot for a mission that you might otherwise...and make a little more propellant on the surface prior to coming back.
(That is a reason that SEP may not really be necessary either.)

Additionally, pure hab space isn't all that heavy.  And if we're talking what the initial several exploration missions will need, we're talking smaller crew of maybe 6 or 7ish, so the hab volume isn't all that much anyway....there won't be 100 people coming at once for a long time.   But they'll need a lot of surface equipment and provisions and supplies for their stay as there won't be anything/much already there.  The cycler doesn't help with that, that needs to be launched from Earth every time.
Then once they get to Mars, they leave that nice cycler hab in space...but will still need one on Mars.  If MArs was habitable, then a cycler could make more sense.  Like a bus.  You ride it there...and get off and stay at your destination.  Then you catch it back, and can travel light.
But people need a place to stay there.  So it's more like an R/V.  They have a place for the trip there, for the stay there, and for the trip back.  IF you need to bring an R/V with you anyway, it doesn't make much sense to tow it where you are going and stay in hotels while traveling, just drive it and live in it along the way. 

Now...down the road when they are moving 100 people at a time, you get into the "bus" model rather than the R/V.  It might make more sense there.  But  your spacecraft is already designed to be large enough to eventually carry and support 100 people to Mars with additional life support and hab volume where the equipment storage was for the exploration missions, so I'm not sure it would serve much purpose even then.  Plus you don't have to worry about missing your cycler rendezvous if your hab is in your spacecraft, or hitting that narrow launch window.  Which I think adds a lot of safety margin.

Online Lobo

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Re: MCT Speculation and Discussion Thread 4
« Reply #875 on: 10/21/2015 07:15 PM »
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.
Possibly but it's also possible that reusable second stage and Mars ambitions combine to make BFR/MCT the next step.
 SpaceX has always been a builder of spacecraft as well as a builder of launch vehicles.

Anything is possible.  We won't know until they see. 

But, "BFR" is a term I think only we've used here on the forums.  I don't think SpaceX or Musk has ever differentiated a HLV and MCT as separate items.  It's always been 'MCT' as I recall seeing.

So I see it as being more like "STS" than "Saturn V" and "Apollo" or "Falcon" and "Dragon" or even "Energia" and "Buran"...as separate systems.

The orbiter was integral to STS, not optional.  You couldn't really unveil the launch vehicle without the orbiter too.

As always, I might be completely misreading EM's intent.  heh.  ;-)




Online RonM

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Re: MCT Speculation and Discussion Thread 4
« Reply #876 on: 10/21/2015 07:31 PM »
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.
Possibly but it's also possible that reusable second stage and Mars ambitions combine to make BFR/MCT the next step.
 SpaceX has always been a builder of spacecraft as well as a builder of launch vehicles.

Anything is possible.  We won't know until they see. 

But, "BFR" is a term I think only we've used here on the forums.  I don't think SpaceX or Musk has ever differentiated a HLV and MCT as separate items.  It's always been 'MCT' as I recall seeing.

So I see it as being more like "STS" than "Saturn V" and "Apollo" or "Falcon" and "Dragon" or even "Energia" and "Buran"...as separate systems.

The orbiter was integral to STS, not optional.  You couldn't really unveil the launch vehicle without the orbiter too.

As always, I might be completely misreading EM's intent.  heh.  ;-)

EM did say MCT would be a system, so I think you are correct. Booster, shuttle, tanker, etc. could be generic names for the components of MCT.

Offline oiorionsbelt

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Re: MCT Speculation and Discussion Thread 4
« Reply #877 on: 10/21/2015 07:35 PM »
I'm pretty sure the term BFR has at least, been used by SpaceX if they didn't coin the term.

Offline GregA

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Re: MCT Speculation and Discussion Thread 4
« Reply #878 on: 10/21/2015 08:18 PM »
I'm pretty sure the term BFR has at least, been used by SpaceX if they didn't coin the term.

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.

Since then some publications have called it a "Big Falcon Rocket". Maybe BFR will stick.

Online Lobo

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Re: MCT Speculation and Discussion Thread 4
« Reply #879 on: 10/21/2015 10:15 PM »
I'm pretty sure the term BFR has at least, been used by SpaceX if they didn't coin the term.

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.

Since then some publications have called it a "Big Falcon Rocket". Maybe BFR will stick.

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.  :-)

 
« Last Edit: 10/21/2015 10:23 PM by Lobo »

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