Author Topic: How BFR Earth-to-Earth Might Actually Get Started  (Read 115693 times)

Offline Coastal Ron

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #420 on: 08/12/2018 08:21 pm »
If 787 is what passes as a huge technological improvement, then sure, I can see why BFR looks like an absurdly big step.

Incremental improvements aside (which admittedly have led to significant safety and efficiency improvements), airliner tech has been pretty stagnant for almost half a century, and few in the industry will admit it. Such people are not good judges about what could happen with improved rocket tech.

the Dreamliner is an amazing step in aviation technology...there is nothing on it that is legacy from previous Boeing designs from the engines to the fly by wire, to the construction and most importantly in the internal systems

It is though, just an incremental change - evolutionary, not revolutionary. For instance, it's still looks the same as every other airliner, and functions the same too.

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in addition it is designed for near complete robotic construction.

No, not at all. You are conflating the lack of human touch labor building the composite sections as meaning most of the aircraft doesn't require human labor. That couldn't be farther from the truth.

And in general, since the dawn of the Industrial Age, industry has been increasingly removing the need for direct human labor for building things, so the 787 production line is just a continuance of that. But the building of an entire 787 is far for "complete robotic construction".

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the BFR is several steps above the Falcon9 and Crewed Dragon of teh same magnitude as the Dreamliners step above the triple seven...

I actually think it will be harder than that, but...

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in my view it will be an engineering miracle of SpaceX does 25 percent of what they are claiming for the BFR...

In a way that is what Falcon Heavy has already proved - because it's about 25% of what BFS will be. So time to move the goalposts...  ;)
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline TripleSeven

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #421 on: 08/12/2018 08:50 pm »
Coastal Ron...thats all wrong  just wrong

"It is though, just an incremental change - evolutionary, not revolutionary. For instance, it's still looks the same as every other airliner, and functions the same too."

no it doesnt...it is the first "non 707 look alike" that Boeing made because the advances in composite construction allowed the airflow models to be more fully  realized.  high subsonic mach flight is very well understood...but go look t the B777 and The Dreamliner...the cockpit noses are very very different...as are the wings. (I had a chance to see one up close recently ...one of the 787's of another airline, hit one of our B777's aft tail cone on the ground...and I am in the "investigation group" )

but the look is meaningless.  It is not an incremental change.  it is as different on the inside as the B707 was from the B377 or the B377 from the B299...

it is fundamental change in technology and technological systems

"No, not at all. You are conflating the lack of human touch labor building the composite sections as meaning most of the aircraft doesn't require human labor. That couldn't be farther from the truth."

nope...the human interaction on the assembly is right now "minimal"" about half what is on the triple which is about 80 percent more than any other Boeing commercial product...and on the Dreamliner it will grow

the inhouse estimate is that in about 5 years 80 percent of the plane will be constructed with no human involvement other than monitoring the robots

its really amazing to walk from the B737 line in Seattle to the 787 line...the 737 is almost all human "work" (it simply cannot be modified to be put together by machines...one reason Boeing wants the 797 to replace it) and go to the Dreamliner line. 

the "big" advantage is also in robotic checkout.  the airplane is not quite R2D2 checking the systems but its amazing close.  the B737's cockpit has to be checked out completely by test pilots...the heavy lifting on systems check in teh dreamliner is all by computers. 

The Dreamliner is just amazing page turner.  Boeing was resistant to the new technology.  Airbus had it easy because they had no legacy of "post bomber" airplane systems to get around.  really the B47 lived on in some form or fashion (systems wise) onto the Triple...but in the dreamliner...its gone

I dont think Falcon Heavy is anywhere near that much of BFS...maybe 5 percent.

Offline speedevil

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #422 on: 08/12/2018 09:05 pm »
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A P2P capable vehicle - one that actually can do 'cheaper than an economy ticket' on some routes - $1M total per flight _price_, would be utterly revolutionary for Mars, compared with one that can do $5M cost.

I'm not sure where you are getting those figures, and certainly a 1-hour flight to the opposite side of Earth is not going to be marketed as "economy". If they do go into this market I think it will be to help fund their Mars colonization plans (directly or indirectly), so they will price it to make a profit.

Elon on instagram.

There are many possible price points. It is not wholly unreasonable to think that he'd want to hit mass market, for the very, very simple reason that if he can, he can now launch, for free, aged-out airframes to Mars, and use the earth passenger craft to launch hundreds of thousands of tons a synod to Mars.
You can do that if you manage to get hundreds of vehicles flying. You can't if you've got one or two serving the luxury market.

And of course, you'd also want luxury flights, with 50, not 1000 people onboard, and going to a nice orbital or lunar resort. Which, again, is enabled by low cargo launch cost.
« Last Edit: 08/12/2018 09:13 pm by speedevil »

Offline Coastal Ron

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #423 on: 08/12/2018 10:38 pm »
nope...the human interaction on the assembly is right now "minimal"" about half what is on the triple which is about 80 percent more than any other Boeing commercial product...and on the Dreamliner it will grow

Yes, incremental changes from a historical standpoint. And of course you are only looking at the final assembly labor for the aircraft, but you could go through all of the sub-assemblies and see that pretty much everyone is making reductions in touch labor.

I remember as the electronics industry was changing from through-hole technology to surface mount. Now THAT was revolutionary, since surface mount allowed for much smaller components, which lead to automated pick & place machines that sound like machine guns. And that was decades ago.

Steering back to the topic at hand, the BFS will benefit from the same composite manufacturing technologies that the 787 benefits from, however the design of the BFS will truly be revolutionary in a number of ways.

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I dont think Falcon Heavy is anywhere near that much of BFS...maybe 5 percent.

The mass of the fully-loaded Falcon Heavy is 1,420,788 kg, and the estimated mass of the BFR/BFS is 4,400,000 kg - that makes the Falcon Heavy 32% the mass of the BFR/BFS.

So while the step up to the BFR/BFS is big, it's not 20X bigger like you are thinking...
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline TripleSeven

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #424 on: 08/12/2018 10:45 pm »
nope...the human interaction on the assembly is right now "minimal"" about half what is on the triple which is about 80 percent more than any other Boeing commercial product...and on the Dreamliner it will grow

Yes, incremental changes from a historical standpoint. And of course you are only looking at the final assembly labor for the aircraft, but you could go through all of the sub-assemblies and see that pretty much everyone is making reductions in touch labor.

I remember as the electronics industry was changing from through-hole technology to surface mount. Now THAT was revolutionary, since surface mount allowed for much smaller components, which lead to automated pick & place machines that sound like machine guns. And that was decades ago.

Steering back to the topic at hand, the BFS will benefit from the same composite manufacturing technologies that the 787 benefits from, however the design of the BFS will truly be revolutionary in a number of ways.

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I dont think Falcon Heavy is anywhere near that much of BFS...maybe 5 percent.

The mass of the fully-loaded Falcon Heavy is 1,420,788 kg, and the estimated mass of the BFR/BFS is 4,400,000 kg - that makes the Falcon Heavy 32% the mass of the BFR/BFS.

So while the step up to the BFR/BFS is big, it's not 20X bigger like you are thinking...

I am trying to stay on topic here.  I suspect the BFR in its first form will be less revolutionary than most here are hoping for...Elon is good at derating things as they move on. and his fans continuing to cheer.....and pretty soon I suspect another "derate" of the BFR is coming

the XC99 lesson and technology problems will slowly creep up on him...and eventually the BFR will turn out to be more a response to BO various rockets than "the mars traveler" or the P2P revolutionary

Mass is not a good indicator of difficulty...sorry
« Last Edit: 08/12/2018 10:45 pm by TripleSeven »

Offline su27k

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #425 on: 08/13/2018 02:46 am »
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A P2P capable vehicle - one that actually can do 'cheaper than an economy ticket' on some routes - $1M total per flight _price_, would be utterly revolutionary for Mars, compared with one that can do $5M cost.

I'm not sure where you are getting those figures, and certainly a 1-hour flight to the opposite side of Earth is not going to be marketed as "economy". If they do go into this market I think it will be to help fund their Mars colonization plans (directly or indirectly), so they will price it to make a profit.

Elon on instagram.

There's also this: https://www.recode.net/2018/4/11/17227036/flight-spacex-gwynne-shotwell-space-ted-conference-interview

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Shotwell estimated the ticket cost would be somewhere between economy and business class on a plane

It's pretty clear they're aiming for turnaround cost a lot lower than Falcon 1 cost (which is where the $5M number comes from).

Offline Coastal Ron

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #426 on: 08/13/2018 04:34 am »
I am trying to stay on topic here.  I suspect the BFR in its first form will be less revolutionary than most here are hoping for...

What are you thinking will be different?

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the XC99 lesson and technology problems will slowly creep up on him...

Only if the Earth-to-Earth version of the BFS is significantly different than the Earth-to-Mars version. Instead of a 60 year old example as analog, I'd say Falcon Heavy could be providing the insight into what BFS will be like, where Falcon 9 and Falcon Heavy share something like 99% commonality.

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and eventually the BFR will turn out to be more a response to BO various rockets than "the mars traveler" or the P2P revolutionary

So you're saying the BFS will be derated to an upper stage?

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Mass is not a good indicator of difficulty...sorry

It's OK to not agree on analogies, but at least I provided quantifiable attributes - all you've provided is the equivalent of "No".

You suggested Falcon Heavy is only 5% close to the BFR/BFS, so please provide some backup for your estimates.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline speedevil

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #427 on: 08/13/2018 09:40 am »
I note the thread BFS - how bad can it be? (and still get to Mars with little delay)

In short - the only critical bits to work to spec are rapid reusability and reliability.

If the engines are no better than Merlins, or the structure is heavier than F9 percentage-wise, or the heatshield can only cope with 4km/s reentry, these do not make Mars particularly more expensive for the first few missions.

The cost of Mars is dominated not by launch costs, but by the cost of having your expensive spacecraft not doing anything economically for years.

However. The threads topic pretty much assumes it works as desired.
« Last Edit: 08/13/2018 12:06 pm by speedevil »

Offline TripleSeven

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #428 on: 08/13/2018 10:10 am »
Coastal Ron

My "guess" right now is that the upper "stage" will soon lose its human capabilities and evolve into just an upper stage...at least at the start

three factors will drive this

First BO is "moving" and in my view their rocket will "leap" Falcon9 and Heavy in some substantial ways...most important is the high energy upper stages... Assuming (I know the first three letters but it probably is a good one) that BO is working out the kinks of re usability with their suborbital flights...and the cost numbers are at least competitive...than Musk will have some competition on his hands...both for commercial and I predict government CREWED business.

Second at some point US space policy concerning SLS/Orion will change.  Orion/SLS is like a person "in quicksand" they are struggling endlessly but in the end sloth inertia bad management decades of fat...are all going to grind the program to a halt...AND there will be either an accident with them OR there will be a new administration that will reverse completely the paths we are on now and that includes the mess that Trump and his predecessors (and the Senate) have made on national space policy

the focus of that change will be spurring private enterprise by some massive (but affordable at the private launch/development price point on dollars already being spent) government effort in crewed flight...and Musk will need to be a part of that to keep the revenue stream going...as well as the launch momentum.   Timing is everything and while I doubt BO flies in 2020 I bet they do by 2022 and BFR has near zero chance of flying in a full up human capable form by 2020 or 22.

third...the "human" part of BFR is the tall stick to me...its like going from a Bass boat to run on the lake to an ocean liner for long cruises...all in one leap and Musk and company has developed some expertise in human spaceflight.  but lets be fair...while there are some neat aspects of the crewed |Dragon (and I have commented on this) Dragon 2 is probably the least capable of the two, the least "expandable" and the learning curve needed to build the human part of BFR is enormous...and there is no market for the  human part of it now.

I think both the technology and the money needed to do it...will eventually overwhelm the need for a new product...

"Only if the Earth-to-Earth version of the BFS is significantly different than the Earth-to-Mars version."

it should be...it would lack solar arrays, massive renewable life support, less food storage, water storage, shielding......just about everything.  I imagine the fuel needed for the landing would be vastly different. but the need to store it for months in thermal cycles would be non existent.  Every kilo that is not needed for the trip would need to be saved for people and cargo to up the revenue seat miles. 

a lot of people here claim Musk is in it to colonize Mars...and he might believe that, but he has to keep the company profitable...and none of the legacy folks now are real competition but BO probably is going to be...

(although some rumors I hear from friends still at Boeing are interesting as well)

we live in interesting times

« Last Edit: 08/13/2018 10:11 am by TripleSeven »

Offline philw1776

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #429 on: 08/13/2018 01:47 pm »
I find it incredible that somehow BO is assumed to have a superior to SpaceX orbital class product early next decade given that BO has zero experience launching anything orbital.  The kinetic energy difference from sub orbital to orbital is huge, so recovery of a suborbital vehicle is nowhere near the difficulty of recovering an orbital vehicle.
For SpaceX to recover and reuse a 2nd stage of an orbital vehicle is not a huge step for them given their Dragon and F9 booster experience.  BFS LEO isn't doing anything not done by the 1970s design Space Shuttle except powered landing (already done routinely by SpaceX) and most importantly economics.  Remains to be seen how much better the economics prove to be.
Both companies are developing new engines. SpaceX has more engine development experience and flight experience, plus they started their big engine R&D several years ago.
I don't see the extreme skepticism about BFS flying its flight profile.  I do see warranted skepticism about timeframe and again most importantly economics.  It's the economics goal that a first generation BFR/BFS may fail, not the operational flight profile goal.
« Last Edit: 08/13/2018 01:48 pm by philw1776 »
FULL SEND!!!!

Online envy887

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #430 on: 08/13/2018 02:03 pm »
Coastal Ron

My "guess" right now is that the upper "stage" will soon lose its human capabilities and evolve into just an upper stage...at least at the start


The cargo version is already baselined to be the first to fly, so in that sense it's lost it's "human capabilities", or rather, never had them in the first place.

Still, it won't be "just an upper stage". No extant upper stage can dock, transfer fuel, reenter, land, be reused, or return downmass. The cargo version will still do those.

Offline TripleSeven

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #431 on: 08/13/2018 02:17 pm »
I find it incredible that somehow BO is assumed to have a superior to SpaceX orbital class product early next decade given that BO has zero experience launching anything orbital.  The kinetic energy difference from sub orbital to orbital is huge, so recovery of a suborbital vehicle is nowhere near the difficulty of recovering an orbital vehicle.
For SpaceX to recover and reuse a 2nd stage of an orbital vehicle is not a huge step for them given their Dragon and F9 booster experience.  BFS LEO isn't doing anything not done by the 1970s design Space Shuttle except powered landing (already done routinely by SpaceX) and most importantly economics.  Remains to be seen how much better the economics prove to be.
Both companies are developing new engines. SpaceX has more engine development experience and flight experience, plus they started their big engine R&D several years ago.
I don't see the extreme skepticism about BFS flying its flight profile.  I do see warranted skepticism about timeframe and again most importantly economics.  It's the economics goal that a first generation BFR/BFS may fail, not the operational flight profile goal.

dont know who is saying that clearly not me.  I think that BO will have some teething issues...but they are second generation or at least the second guy to do it, and between the people that they have hired from SpaceX and just following along, doubtless they have learned some things..

Of course the bulk of the experience is as you point out with SpaceX and they have a massive data base of flight data points...

all I think BO will do is add competition where now really none exist

Offline TripleSeven

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #432 on: 08/13/2018 02:19 pm »
Coastal Ron

My "guess" right now is that the upper "stage" will soon lose its human capabilities and evolve into just an upper stage...at least at the start


The cargo version is already baselined to be the first to fly, so in that sense it's lost it's "human capabilities", or rather, never had them in the first place.

Still, it won't be "just an upper stage". No extant upper stage can dock, transfer fuel, reenter, land, be reused, or return downmass. The cargo version will still do those.

Just a guess...but I suspect a lot of that capability will not be available for Block 1. 

Online envy887

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #433 on: 08/13/2018 02:32 pm »
Coastal Ron

My "guess" right now is that the upper "stage" will soon lose its human capabilities and evolve into just an upper stage...at least at the start


The cargo version is already baselined to be the first to fly, so in that sense it's lost it's "human capabilities", or rather, never had them in the first place.

Still, it won't be "just an upper stage". No extant upper stage can dock, transfer fuel, reenter, land, be reused, or return downmass. The cargo version will still do those.

Just a guess...but I suspect a lot of that capability will not be available for Block 1.

You think they are going to expend the upper stage? Why? BFR with an expendable upper stage has little point. They might as well use Falcon Heavy.

I think all of those will be available from the first orbital launch. Perhaps not all used initially (e.g. docking/refueling and downmass), but those features will be designed into the vehicle.

Offline Coastal Ron

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #434 on: 08/13/2018 02:57 pm »
My "guess" right now is that the upper "stage" will soon lose its human capabilities and evolve into just an upper stage...at least at the start

So you think the BFS portion of the BFR/BFS system will just be used for boosting payloads? What payloads?

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First BO is "moving" and in my view their rocket will "leap" Falcon9 and Heavy in some substantial ways...most important is the high energy upper stages...

How is Blue Origin "moving"?

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Assuming (I know the first three letters but it probably is a good one) that BO is working out the kinks of re usability with their suborbital flights...and the cost numbers are at least competitive...than Musk will have some competition on his hands...both for commercial and I predict government CREWED business.

1. We know cost is not a significant factor for Blue Origin because Jeff Bezos is willing to provide them with $1B/year - maybe forever.

2. As it stands, the U.S. Government won't need Commercial Crew services after the ISS is gone, which could be as early as 2024. Blue Origin won't have an opportunity to participate.

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Second at some point US space policy concerning SLS/Orion will change.

Congress created the SLS and Orion for future government needs, and what Elon Musk and Jeff Bezos do with rockets has no affect on what Congress wants to spend money on.

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the focus of that change will be spurring private enterprise by some massive (but affordable at the private launch/development price point on dollars already being spent) government effort in crewed flight...

You think the government will be spending massive amounts of money sending humans to space? Call me a skeptic...

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third...the "human" part of BFR is the tall stick to me...its like going from a Bass boat to run on the lake to an ocean liner for long cruises...all in one leap...

Yep. Even Elon Musk is awed by the scale of that leap. Yet humans have gone from Bass boats to ocean liners. And remember the ultimate BFR is bigger than the version they are starting with, so SpaceX did decide on an intermediate version first.

Yet we wander. The topic of the thread is not how an Earth-to-Earth transportation system WON'T get started, but how it will. So let's get back to that.

If anyone wants to be a skeptic of the BFR, then there is a thread for that...  ;)
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline TripleSeven

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #435 on: 08/13/2018 03:25 pm »
Coastal Ron

My "guess" right now is that the upper "stage" will soon lose its human capabilities and evolve into just an upper stage...at least at the start


The cargo version is already baselined to be the first to fly, so in that sense it's lost it's "human capabilities", or rather, never had them in the first place.

Still, it won't be "just an upper stage". No extant upper stage can dock, transfer fuel, reenter, land, be reused, or return downmass. The cargo version will still do those.

Just a guess...but I suspect a lot of that capability will not be available for Block 1.

You think they are going to expend the upper stage? Why? BFR with an expendable upper stage has little point. They might as well use Falcon Heavy.

I think all of those will be available from the first orbital launch. Perhaps not all used initially (e.g. docking/refueling and downmass), but those features will be designed into the vehicle.

I was careful though imprecise in my words.  I suspect that the first "block" of the second stage will be capable of delivering a payload...and recoverable...but not much else.  I think those come in subsequent "blocks"

the main thing that makes it "a better" launcher is the high energy upper stage

Offline TripleSeven

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #436 on: 08/13/2018 03:35 pm »
Coastal Ron

no point in replying to all the points you made because i think my original post that you replied to answered them

this was interesting

"
So you think the BFS portion of the BFR/BFS system will just be used for boosting payloads? What payloads?"

initially I think that the new rocket will function as a quite conventional booster system...with hopefully both stages recoverable.  what payloads...the same one Falcon9 and H are into now...

this is where they are going to run into competition from BO; who is sizing their vehicles for three markets...1. some kind of US government lunar push (when and if SLS ends), 2) larger military payloads, 3 commercial payloads like comsats as well as some kind of low earth orbit space station operation.

and it is this competition that I think will migrate the early introduction of a "new" booster with BFR/BFS as the core of it...

if the price points on BFR/BFS and BO stuff are as low as everyone is expecting well they will both be in competition with themselves not really Boeing or anyone else, assuming that the other companies keep on with their stated plans

in my view everything else will develop from that first Block 1 version...the Mars ship the P2p etc...depending in large measure how the economics work out

and you are correct so well if we want to continue this then maybe the other thread is the place to do it


Online envy887

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #437 on: 08/13/2018 03:45 pm »
Coastal Ron

My "guess" right now is that the upper "stage" will soon lose its human capabilities and evolve into just an upper stage...at least at the start


The cargo version is already baselined to be the first to fly, so in that sense it's lost it's "human capabilities", or rather, never had them in the first place.

Still, it won't be "just an upper stage". No extant upper stage can dock, transfer fuel, reenter, land, be reused, or return downmass. The cargo version will still do those.

Just a guess...but I suspect a lot of that capability will not be available for Block 1.

You think they are going to expend the upper stage? Why? BFR with an expendable upper stage has little point. They might as well use Falcon Heavy.

I think all of those will be available from the first orbital launch. Perhaps not all used initially (e.g. docking/refueling and downmass), but those features will be designed into the vehicle.

I was careful though imprecise in my words.  I suspect that the first "block" of the second stage will be capable of delivering a payload...and recoverable...but not much else.  I think those come in subsequent "blocks"

the main thing that makes it "a better" launcher is the high energy upper stage

It needs to be more than recoverable. It needs to be reusable. And everything for reuse will be baked into the first vehicle.

The first BFS to fly to orbit will not be the first one they build. What you're calling "block 1" will be the suborbital hop test vehicle. That will likely start as the minimum viable vehicle that can hop to low altitudes and be reused, then either be modified or replaced with a vehicle that can launch to suborbit and replicate orbital entry heat loads with reuse.

By the time a BFR/BFS launches to orbit, the BFS will likely be several "blocks" along in its design iteration, and likely at least to the point of a modestly reuseable cargo vehicle, including entry, landing, reuse, and downmass capabilities.

There is no need for a higher energy stage than Falcon Heavy already has, other than supporting BLEO HSF activities. And there are no customers for that besides NASA at the price point where a expendable (or recoverable but not reusable) upper stage necessarily dictates.

Offline MikeAtkinson

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #438 on: 08/13/2018 06:07 pm »
What little we know about how SpaceX are going to test BFR/BFS is that they are going to start with a ground launched BFS (block 1) which will be rapidly reusable and is intended to be SSTO (or almost so) with no payload.

Any talk of BFS early blocks being an expendable second stage not only goes against every statement from Elon Musk, Gwynne Shotwell and others, but also against what we know of the cost structure. It is not financially viable for SpaceX to expend a BFS (which will be over $100 M even without recovery hardware).

Offline Lar

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Re: How BFR Earth-to-Earth Might Actually Get Started
« Reply #439 on: 08/13/2018 11:14 pm »
Luck is being prepared and then being in the right place. Was Musk lucky? Ssure. But betting against him, as 777 does, here and in other threads? bad idea.

And getting back to "time" being what people are paying for, today the longest airline routes take 17 hours, so in order for a BFR point-to-point service to work there needs to be a large enough population of well off people that value time more than money.
Many consultants bill at 200, 300, even 500 USD an hour. Save 16 hours each way and you may be able to bill for a good part of that. That might, or might not, form part of the market.
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

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