Deep space gateway thread

If they had any sense. They would park it in the L4 or L5 orbit. then build a rotating torus hab section spinning for 1/3-1/2 G. Just enough to eliminate the hardships of living in freefall.

Partial gravity is really top priority stuff, but there's no reason to do it outside of LEO. They should just do a can and tether station, as soon as possible. Lunar gravity first, see how people stand up to a year of it. Better yet, send two up at once, one for lunar, one for Martian. They can launch them on Falcon Heavy, then crew them with Dragon.

Because its a dumb meme & a scam that will never see flight
Just like all the other space scams over recent history

>park it really far away for no reason
>And then make it really fucking big + spinning

genius idea
How many hundreds of years will it take the SLS to build it, assuming a normal 1 launch per 4 years rate.

This times a million I used to be in SLS camp, After waiting umpteen years for its first flight and watching constant delays as well as funding cuts and other bullshit I have given up on this pork barreled project.

Fucking hope to god someone kills off SLS and replaces it with something reusable like what musk Has but cooler and actually reusable
Fucking hate how Spacex trys to build something that looks cool but takes forever

Just build something that works nobody gives a shit about how "sleek" a rocket looks or how "cool" a space suit looks, just build something durable that fucking works, maximize utility minimize bullshit

>Will moon landing deniers finally shut the fuck up when we go back?

No.

If their conspiracy theories were driven by facts, and refutable by facts they'd have shut up already.

>They should just do a can and tether station, as soon as possible.

Not that this is impossible, but the use of "just" implies it will be easy. For a variety of reasons, that is unlikely to be the case, given our admittedly-very-limited experience.

Doesn't take much to jostle the counterweights enough to fuck things up.

>nobody gives a shit about how "sleek" a rocket looks or how "cool" a space suit looks,

I think you're wrong there. PR/Publicity is a big part of a business, and look how much drooling, unquestioning press these companies get when they unveil something glittery and cool, be it a new space suit design or the announcement that some secretive gazillionaire has chartered a flight around the moon half a year earlier than some competitor's plan.

If you want the commercialization of space-flight, the commercial part is unavoidable.

>Fucking hate how Spacex trys to build something that looks cool but takes forever
Dude, they are moving fast. They were only founded in 2002. They had a vehicle ready to fly in 2005, reached orbit in 2008, demonstrated a practical launch vehicle and capsule in 2010, commercial GTO launch in 2013, stage recovery in 2015, reuse and market domination in 2017. By 2022 they'll likely have BFR flying, fully reusable. This stuff is hard, it takes time, and there are a lot of regulatory hurdles in the way.

BFR isn't designed for looks, but for function. It must be sleek to be aerodynamic. They tried to avoid wings and make it as close to simple cylinder as possible for mass efficiency, but in simulation, found the wings to be unavoidable if they wanted to be able to accommodate a variety of mass distributions (i.e. be able to land payloads on Earth, including passengers and their necessary accommodations).

>how "cool" a space suit looks
Ah, that's a different matter. That's a relatively small project, and they want to put in the extra effort to make it look good so it's easier to sell space tourism as something cool and elite rather than dorky and utilitarian. Again, though, a spacesuit should look good to function well: to be comfortable, to not be cumbersome, to not catch on things, to give freedom of movement, to be simple and easy to understand. While it's possible to make it look good and work badly, if it looks bad, it's going to work badly in some way, such as being bulky or having complicated surface features which snag on things. As it approaches functional perfection, it will necessarily become aesthetically pleasing.

>By 2022 they'll likely have BFR flying, fully reusable.
Just like they had falcon heavy flying back in 2010 amirite?

>the use of "just" implies it will be easy. For a variety of reasons, that is unlikely to be the case, given our admittedly-very-limited experience.
It's a very simple thing as long as you don't try too hard to optimize it. For instance, design it so orientation with respect to sunlight doesn't matter. That's not hard, but takes significant additional mass and expense (more solar panels and radiators).

>Doesn't take much to jostle the counterweights enough to fuck things up.
Nonsense. In the first place, there's basically nothing up there to jostle it. Secondly, all you need are some shock absorbers on the cable to damp down any swinging that gets underway. Two weights spinning on the ends of a cable is a very stable system.

The reason it hasn't been done yet is that it would call into question the necessity of all of the research into the long-term effects of zero-g, and development of zero-g systems for manned spaceflight. There's been huge investment in this, and many people have based their careers on it. If we recognize that artificial gravity is easy and beneficial enough that we should always use it for long-term manned spaceflight, it would all have been for nothing. It's similar to how they wouldn't cancel the shuttle even though it was clearly a failure.

This

>there's basically nothing up there to jostle it.
just like people inside it? Space craft docking ? Moving shit around ?

Rigid is not any harder or heavier than a tether

They want to drag out things so that people will forget the abomination that was the Space Shuttle, forget the justification for the ISS, and think that NASA wasn't wasting hundreds of billions doing makework for 5 decades.

Falcon Heavy was always a side project of the Falcon 9 vehicle, and SpaceX had to grow from a tiny design+prototype+demonstrate company into one capable of meeting routine production and operation targets. BFR is SpaceX's primary ambition, and it's a mature company of thousands now, with a large factory it will soon mostly no longer need for Falcon 9, thanks to reusability, and with a reliable revenue stream and terrific investor enthusiasm.

The Falcon Heavy 1.0 concept, considered necessary for commercial GTO launches, was made obsolete by the enhanced performance of Falcon 9 1.1. The current remaining primary justification for the development of Falcon Heavy is to enable reuse on launches using the full expendable capacity of Falcon 9, so it made little sense to complete it until Falcon 9 lower stage recovery (downrange landing in particular) was working reliably.

The delays in Falcon Heavy's debut aren't some worrisome failure, but a byproduct of SpaceX's flexibility and high aspirations. They've achieved things with Falcon 9 that were unhinted-at in 2010.

2022 is still five years from now. They've already been working on BFR for six years, and have demonstrated a prototype engine and tank. It only took them five years to get from the first succesful orbital flight of Falcon 1 to Falcon 9 1.0 and Dragon. It only took five years for the Saturn V team to get from final concept to first flight.

It's possible that they'll take longer, but not likely that they'll take a lot longer. It wouldn't surprise me if they had prototype hardware (a Grasshopper-like test flight vehicle) flying as early as next year.

I think you'll find that making these things "look cool" is about 1% of the time investment of making them actually work reliably and not kill the user(s).

>>there's basically nothing up there to jostle it.
>just like people inside it?
They're not going to significantly disturb the spinning just by moving around.

>Space craft docking ?
It's not necessary to have spacecraft docking during a long-duration mission. You just load up enough supplies for the full length.

>Rigid is not any harder or heavier than a tether
That's crazy talk. First of all, how do you deploy the long rigid connection between the counterweight and the crew can? With a cable, you simply start a slight spin and slowly unspool it, and then you can perform the exact operation in reverse. What magic do you use to keep it as light as a simple cable between them?

We're talking about a small test unit, maybe 30 tonnes, just enough for two people to live in as an experiment on their health. If the RPMs are to be low enough for comfort, it needs to be very long and thin. The obvious design is a tether-counterweight system.

>Deep Space Gateway

Good idea, finally building some permanent deep space infrastructur-

>in a crazy NRHO orbit instead of a cozy Largange point
>no propellant depot
>a shitty tiny tin can instead of actual space station

Just when you thought NASA got their head out of the ass this shit happens.

>Falcon Heavy was always a side project of the Falcon 9 vehicle
BFR is a side project of SpaceX.
They don't need it to do any of their current launches.

BFR isn't a side project, it's the reason SpaceX exists, the vehicle SpaceX was founded to develop.

They won't sideline F9 and FH to work on BFR just like they didn't sideline F9 to work on FH

This is especially true once commercial crew gets going

There's no way that BFR launches before December 2024.

>They won't sideline F9 and FH to work on BFR
Yes they will. They'll declare F9 and FH finalized, cease development efforts, stop building boosters, reduce factory space to that necessary to produce upper stages, and transfer resources to BFR. Block 5 is the final Falcon 9. They're going to spend another year or two building boosters, and then they won't need any more.

Shortly after BFR starts flying, F9/FH will be used only to serve a few legacy contracts with inflexible customers, because BFR will be cheaper to fly on a per-launch basis, and more capable in every way.

>just like they didn't sideline F9 to work on FH
This wasn't possible because FH was always an F9 variant. The logical time to start flying FH is when the F9 design has stabilized, so they don't have to repeat the development effort, and that's what they're doing.

>There's no way that BFR launches before December 2024.
You've got nothing to base that on.

>Yes they will. They'll declare F9 and FH finalized, cease development efforts, stop building boosters, reduce factory space to that necessary to produce upper stages
They won't stop building boosters as long as commercial crew and military payloads are available.

>and transfer resources to BFR
they have to build a whole new factory to build BFR
they also need a huge ship to transport the pieces across the canal

>Shortly after BFR starts flying, F9/FH will be used only to serve a few legacy contracts with inflexible customers
this will happen in the 2028-2030 timeframe at best

>This wasn't possible because FH was always an F9 variant. The logical time to start flying FH is when the F9 design has stabilized, so they don't have to repeat the development effort, and that's what they're doing.
that's complete bullshit
the first falcon heavy will use stages that were built literal years ago

>You've got nothing to base that on.
timeline of Falcon Heavy

It will fly before December 2024 but likely not to Mars like Elon predicted; I estimate that it will start testing 2022, go to the Moon in 2025-6 and finally go to Mars from 2028-2030.

>They won't stop building boosters as long as commercial crew and military payloads are available.
They only need so many boosters, when they have 50-100 of them sitting in warehouses that'll be enough forever

>this will happen in the 2028-2030 timeframe at best

Delusion, doesn't take THAT long to build a rocket, and I guarrentee that this whole rushing to mars thing is going to be put on the backseat for years of satellite + lunar + probe + space station launches.

Falcon Heavy made no sense at all for them to build before they had reuse. It made no sense when an uprated F9 is going to cover its niche. It made no sense when they had more contracts than they could do launches.
NOW it makes sense because they have old stages + reuse is perfected.. plus they will have 3 launch sites.

I guarrentee they wish they had not proposed the Falcon Heavy and not accepted contracts for it, which forces them into building it/launching it.

>They only need so many boosters, when they have 50-100 of them sitting in warehouses that'll be enough forever
doesn't matter when 100% of their customers won't accept reused boosters, especially commercial crew
you can expect lawsuits up the ass if they ever cancel that deal

>Delusion, doesn't take THAT long to build a rocket
FH was supposed to fly in 2010
it won't until 2018

A first flight for BFR of 2024 is actually generous because it shaves off 2 years from what it took FH to launch.

>I guarrentee they wish they had not proposed the Falcon Heavy and not accepted contracts for it, which forces them into building it/launching it.
Are you retarded?

>when 100% of their customers won't accept reused boosters

?? Who told you this nonsense
All of them will accept reused boosters for a reduced price

Or if people want to continue paying extra for a new booster(new boosters are LESS SAFE btw), then they will keep assembly lines open

The FH is fundamentally different from the BFR
The delays of the FH were dictated by delays & changes in the F9 problem
The BFR is totally unrelated to the F9, it will procede at its own pace then launch as soon as its ready, from the south texas pad probably.

>Are you retarded?
Are you? FH will have less profit margin than the F9, anything the FH launches could have been done with upper stage refueling + two launches of the F9

It's a new rocket, its a risk to their pad & launch rate. It can and probably will have failures
Big risk for negligible gain, also the cost of the FH program for something that'll only fly a handful of times.

>All of them will accept reused boosters for a reduced price
What are you basing that claim on?

When a booster carries a $5 billion payload or 5 humans the customer will always go with the safe rather than the cheap option.

>The FH is fundamentally different from the BFR
You're right
It uses 100% new hardware compared to FH which is only 30% new hardware.

>from the south texas pad probably.
nope

upper stage fueling doesn't exist and the closest people to mastering it are not spacex

>go with the safe
A booster that has flown 15 times is a lot safer than a brand new never flown booster.
You know everything in it works

>It uses 100% new hardware compared to FH which is only 30% new hardware.
And when it's reused hardware is constantly changing, plus they don't have a supply of it since the F9 program gets first dibs on all boosters, obviously the low priority program ends up delayed.

>nope
yup

It's not something that is hard
Just would take money and a few launches to test, and likely some solar panels for longer duration + active temperature management.

Would have been a lot easier than producing the Falcon Heavy.

>A booster that has flown 15 times is a lot safer than a brand new never flown booster.
>You know everything in it works
You have nothing to base that on.

>And when it's reused hardware is constantly changing
FH will use block 3 cores which "stopped changing" in late 2014

>yup
nope
they can't evacuate the whole town for every launch

>It's not something that is hard
more baseless claims

>They won't stop building boosters as long as commercial crew and military payloads are available.
You seem confused. They don't need to keep producing boosters to keep flying F9 and FH, because the boosters are reusable. They'll build a sufficient inventory, and that'll be all they need.

>they have to build a whole new factory to build BFR
They only need a tank fabrication / assembly plant. Most of the work is building the engines and other major components, which they can do in their existing factory.

And they don't need it for the initial prototypes, just for routine production. (remember, they've already somehow built and transported a 12m diameter prototype tank, larger than the BFR diameter)

>they also need a huge ship to transport the pieces across the canal
1) BFR's not big as ships go, especially if you stand it upright (which it's easily light and strong enough for). This is a routine shipping task. They can hire a ship (or a barge and tug), don't need to buy or build a special one.
2) They're planning on building "floating spaceports", based on their current droneships (which are going to undergo incremental upgrades to allow downrange-landed F9/FH stages to be partially refuelled for prompt reflight back to land), and it's likely that the first BFR flights will be from one, to minimize the regulatory hurdles and risk to other facilities. They'll have the option of transporting it on that, though an ordinary barge probably makes more sense.

>the first falcon heavy will use stages that were built literal years ago
...with software and modifications finalized only this year. Plus they know how what they've got will differ from the final product. The first Falcon Heavy is a throwaway prototype. Parts are outdated, but it makes more sense at this point to fly them and see if they learn anything important.

>timeline of Falcon Heavy
I've already explained why it's not representative. Again: FH is a configuration of F9.

>They don't need to keep producing boosters to keep flying F9 and FH, because the boosters are reusable.
some customers will refuse to fly on used boosters

>They only need a tank fabrication / assembly plant.
only

>And they don't need it for the initial prototypes, just for routine production. (remember, they've already somehow built and transported a 12m diameter prototype tank, larger than the BFR diameter)
they can't build the prototypes in the existing factory
it literally cannot fit through the streets of LA

>1) BFR's not big as ships go, especially if you stand it upright (which it's easily light and strong enough for). This is a routine shipping task. They can hire a ship (or a barge and tug), don't need to buy or build a special one.
the point is that they have to transport it and that will take weeks

>2) They're planning on building "floating spaceports", based on their current droneships (which are going to undergo incremental upgrades to allow downrange-landed F9/FH stages to be partially refuelled for prompt reflight back to land), and it's likely that the first BFR flights will be from one, to minimize the regulatory hurdles and risk to other facilities. They'll have the option of transporting it on that, though an ordinary barge probably makes more sense.
complete bullshit
the video you are referencing took some heavy artistic liberties

>Plus they know how what they've got will differ from the final product. The first Falcon Heavy is a throwaway prototype. Parts are outdated, but it makes more sense at this point to fly them and see if they learn anything important.
the same is true for every flowing and flying falcon 9
"continuously upgrading f9" is a dumb redditor excuse for not flying falcon heavy

>I've already explained why it's not representative.
no, you haven't

>Again: FH is a configuration of F9.
that means it should have been finished faster not slower

only way for glorious space colonization to happen is if NASA is burnt to the fucking ground

flown* and flying

>some customers will refuse to fly on used boosters
those customers will pay higher prices then, Simple

>they can't build the prototypes in the existing factory
so you make a new factory for it, It's planned to mass produce these things, and they fully plan to go all fucking in on the BFR, so the factory will be required inevitably
>it literally cannot fit through the streets of LA
why the fuck does it need to go through the streets of a city
go around for fucks sake, or build the factory near a harbour so you can avoid it entirely

>the point is that they have to transport it and that will take weeks
why would it take weeks?
sure it'll take a while, ALL shipping does, but that's why you have multiple rockets in service, use the ones ready to go while waiting for the shiny new ones to arrive

>complete bullshit
>the video you are referencing took some heavy artistic liberties
says who? can you explain how a ship magically cannot exist, even though ships of significantly greater size and strength are built on a regular basis?

>that means it should have been finished faster not slower
as it turns out, rockets are pretty complex things, and some unexpected issues appeared that they had to fix and design around
these things tend to add extra time

>some customers will refuse to fly on used boosters

Which customer demands to only ship products on brand new ships or planes or trucks?
What an absurd thing to say
The customer will take what they are offered

>they can't build the prototypes in the existing factory
They could, and they can build everything else that goes into it other.
They might choose not to, for optimization reasons.
It DOES fit through the streets, it's just a big headache + costs alot of money

>"continuously upgrading f9" is a dumb redditor excuse for not flying falcon heavy

This is their actual reason that they CHOSE not to develop a Falcon Heavy & burn 3 F9 boosters at once

>some customers will refuse to fly on used boosters
Not going to happen. They're going to stop offering the option of flying on new boosters. Maybe a few customers will fly on other launch services because of it.

>>They only need a tank fabrication / assembly plant.
>only
Yes, only. They're scouting locations now. It can almost certainly go in an existing building, such as a warehouse. There'll be relatively few workers, since they'll be doing everything they can in their current factory.

>it literally cannot fit through the streets of LA
It can, it's just expensive and inconvenient. They have to take traffic lights down. They were considering it as an option, but it would cost something like $20 million each time they did it. Those costs are bearable once or twice.

>they have to transport it and that will take weeks
So what? Anyway, initial testing will likely be at Vandenburg, or rather well offshore from it, not all the way on the other side of the country from their factory.

>complete bullshit
Do the background reading before arguing. The "floating spaceport" is part of their plans, and will likely be used for their testing.

>the same is true for every flowing and flying falcon 9
This doesn't make any sense. Falcon 9 is the single core, basic configuration of F9/H. There's roughly one third as much hardware involved, and the pad facilities required are at one third the scale. Flying in this minimal configuration makes far more sense for incremental development, when each flight involves one third as much stuff, and only committing to the superheavy configuration when the major changes have stopped.

The first Falcon Heavy launch isn't carrying any payload. It's purely a test flight. It's not at all the same thing as the F9 flights they've been doing.

>dumb redditor excuse
Assclown.

>>Again: FH is a configuration of F9.
>that means it should have been finished faster not slower
That means it's not a separate vehicle development project. It's not an example of a vehicle development project. It's a feature of Falcon 9, and the Heavy configuration they're doing now is significantly different from the one originally estimated to be completed in 2010, which was superceded by Falcon 9 performance upgrades. They found a better, less expensive way to put GTO payloads into orbit, and you're trying to spin that as some kind of negative indicator for their future success.

You might as well try to argue that since they never got first stage parachute recovery working, that proves they don't make their reusability plans work. What you're saying is just that stupid.

Can someone do a rightful photoshop of this except with Elon and suborbital rocket dude/ Blue origin/ULA/old aerospace

...

...

Docking with that would be a pain in the ass.

Since there is no Falcon9 launch today... do you wanna watch ULA Delta II launch with me? It's on right now:
spaceflightnow.com/2017/11/13/delta-2-jpss-1-mission-status-center/

Something is "no go"

HOLD HOLD HOLD.
Launch window expired.
Not only Falcon 9.

>spacex
>vab

>FH will use block 3 cores which "stopped changing" in late 2014

No, it will first fly with previously used block 3 cores, but that's because it's what SpaceX had/could spare from the Falcon 9 side of things. The cores themselves have been almost entirely overhauled and significantly modified compared to Falcon 9 cores. Falcon Heavy will still be in development after its first flight, in order to bring it up to what will be the modern block 5 variation, which has all the tweaks and changes that make reusability many times easier.

The reason it took several years to go from flown boosters to finished cores is because those years are just what it took to figure out how to do Falcon Heavy and to actually strip down and modify the cores.

>they can't evacuate the whole town for every launch

They can pay everyone in the town to leave.

>more baseless claims

The problem is not figuring out propellant transfer, the problem is trying to get funding to do. For some reason NASA is totally disinterested in orbital refueling to the point that any proposal that considers it is essentially ignored. Since SpaceX is developing BFR by themselves they can develop propellant transfer on their own.

>The reason it took several years to go from flown boosters to finished cores is because those years are just what it took to figure out how to do Falcon Heavy and to actually strip down and modify the cores.
There was also that tiny little matter of the pad-shattering kaboom. Getting 40 back up was a priority, now they can finish the last modifications that 39A needs for FH.

The larger problem with in-orbit refuelling is finding a context where it makes sense. When you've got fully-reusable rockets with storable propellants or high-boiling propellants at a scale where boil-off is measured in years, it's a no-brainer. With less than that, it gets very hard to justify.

ULA's ACES-refuelling plan was basically a petition for the US government to give them unlimited money for not accomplishing much. They would launch expendable rockets with expendable upper stages to fill a special, expensive propellant depot (another moneypit space station), so they can do departure burns with loads limited to what they can launch into LEO with ordinary-size rockets with ordinary-size payload fairings. You're talking about $billion+ per-launch unit costs, on top of multi-billion dev costs. It only looks good by comparison with SLS/Orion, a program more dedicated to spending money than to achieving results.

SpaceX's BFR-refuelling plan is to launch highly reusable rockets with highly reusable upper stages to simply dock with and refuel other reusable upper stages, on top of superheavy capacity to LEO complete with 8-meter fairings, and having chosen the absolute cheapest propellants. And due to the elegance of the design, they'll get the capability practically for free.

It would have made sense with the Falcon too if that was the route they decided to go for larger payloads to GTO/deep space probes

And if they ever reach a point where their launch backlog is mostly gone

>It would have made sense with the Falcon too
It would take a lot of changes to the upper stage. Enough that it's probably not much cheaper, easier, or faster than developing BFR. The Falcon 9 upper stage:
- has no insulation
- has no long-duration power system
- can't dock
- uses two main propellants such that one freezes at the temperatures needed to keep the other from boiling
- uses three other consumable fluids, almost certainly four or five in a docking-capable configuration
- uses one low-volatility propellant (RP-1) that needs purging after disconnection, merely exposing it to vacuum won't clean up residue promptly
- is small enough that fixing all of this stuff would involve significant relative mass penalties
- has quite a limited payload to LEO, especially in terms of fairing diameter

It makes sense to develop upper stage reusability, upper-stage/spacecraft integration, and in-space refuelling at the same time, and to do it as a methane-fuelled superheavy.

BFS (BFR upper stage) will be a well-insulated, long-duration spacecraft with docking, which uses only two consumable fluids which are both highly volatile and liquid at the same temperature, and is big enough to make this all mass-efficient (particularly the insulation, which involves a square-cube law) and to carry payloads as large as any other plausible alternative.

>Enough that it's probably not much cheaper, easier, or faster than developing BFR.
Eh
I'm talking about them starting this Falcon Upper stage refuel idea back at a similar time to when they started the Falcon Heavy, as a replacement for the Falcon Heavy design.

I think you exagerate how much it would cost or how difficult it is to make these changes, to add some deployable solar panels, spray a little insulation, add a cooler for the LOX and a heater for the RP-1, and add some maneuvering thrusters for the docking.

Obviously there is no point for them to develop this today, but it would have been a practical "replacement" for the Falcon Heavy launching high velocity payloads to GTO or the moon/mars.

It's the same story: they would have looked at what it takes to do it, and realized that it made more sense to develop a whole new vehicle instead. In fact, that's a big part of what happened.

Falcon 9 has many things which they did out of inexperience, limited resources, and a need to get flying. They don't want to live with that technical debt forever. They want higher specific impulse, lighter tanks, and all that. There are also things they got right, that they don't want to lose, like commonality between the upper and lower stages.

The relative costs of things can really surprise you. For instance, the Dragon capsule costs about as much as a complete Falcon 9 per unit, and it also cost about as much money to develop. Making a Falcon 9 upper stage capable of waiting in orbit and docking would probably add as much cost per unit as putting a Dragon on top of it, and a fair fraction of the mass. So it's not going to be the cost of three launches for triple the payload, it's going to be more like the cost of six launches for double the payload. As for development, that would be complicated, and might take years to get it working right after they started, if they tried to tack it onto a system not designed for it from the start. The stuff I pointed out about the inconveniences of RP-1, helium pressurization, and insulating a small vehicle are all serious technical challenges.

Boeing/ULA has wanted to do ACES since 2006, and is currently talking about maybe doing it twenty years later. Why is it so hard for them? They have to handle liquid hydrogen, and its very low boiling point and heat of vaporization, and its problems coexisting with the much warmer liquid oxygen. They have to put it on a smallish upper stage, so it's mass sensitive. It (particularly in its tanker form) is not going to be reusable, so it's cost sensitive. They didn't avoid most of the problem at the napkin sketch stage.

For that it is even worse than a normal TSTO.
It is complex and uses expensive hydrogen while provides mach5 max separation speed and 20-30km altitude while reusable rockets provide mach8-10 and 100km alt.
Skylon is stupid meme from 90s SSTO fad and slush hydrogen era

>For instance, the Dragon capsule costs about as much as a complete Falcon 9 per unit, and it also cost about as much money to develop.

That is because its NASA funding the Dragon Capsule, and they have to jump through NASA hoops + do things NASA's way.
So they end with NASA-tier costs
A thing done inhouse for their own purposes would have a very different schedule & cost.

>Boeing/ULA has wanted to do ACES since 2006, and is currently talking about maybe doing it twenty years later. Why is it so hard for them?

Their launches cost hundreds of millions, they can't afford to do orbital tests of any systems. They aren't funding it or seriously persuing it. Thats more a sales pitch to the government than a real idea.

>provides mach5 max separation speed and 20-30km altitude
That's just where they'd stop airbreathing flight. They could still pop up to 50-80 km on rocket power and mach 6-9 if they want it to, and separate in what is effectively vacuum. The Falcon 9 booster only goes to about mach 6 for flyback landings.

Burning hydrogen isn't pure disadvantage, either. In a decade or so, solar electricity will likely be cheaper than fossil fuels, and the regulatory environment around burning carbon fuels can't be predicted. Liquid hydrogen could be very cheap if it's not a special order. Anyway, it'd be more energy efficient than a rocket at taking off, climbing to the stratosphere, and accelerating to mach 5 because it's airbreathing.

I still say SABRE is interesting tech. The SSTO Skylon will too many problems with hitting the mass targets needed to make orbit with a good payload, though. There are all sorts of ugly requirements like passengers can't have windows and unpowered landings.

Falcon uses primitive engines and goes over mach8 in downrange landings.Glenn will use better engines and downrange landings with velocities beyond mach 10.For hydrogen to be cheaper and better due to low impulse volumetric density you would need nuclear fusion level of cheap electricity without that it will be made out of natural gas that is the cheapest source of energy on the planet.LOX is dirt cheap and with cheaper energy it is basically free compared with LNG

>That is because its NASA funding the Dragon Capsule, and they have to jump through NASA hoops + do things NASA's way.
>So they end with NASA-tier costs
NASA also funded Falcon 9 and SpaceX had to satisfy them that it was adequate as well. By the way, I was talking about cargo Dragon. NASA's squeamishness about certifying an actual crew vehicle is another story.

Launch vehicles are big, but relatively straightforward: propellant tanks, engines, short-term battery power and guidance. If the conditions are bad or unexpected and worrisome, you don't fly them. Spacecraft are robots that need to live on their own in the wild for months or years, while doing a useful job. People aren't kidding when they say that the satellites usually cost more than the rockets that launch them, and unlike the rockets, they're mostly built by private industry trying to keep costs down so they make a profit.

Making an upper stage into a spacecraft is a big deal. The BFR upper stage, even the simplest version (the tanker), is probably going to cost upwards of $100 million (with passenger versions closer to $200 million), whereas the F9 upper stage costs more in the neighborhood of $3 million. A lot of that additional cost is scale-invariant, and would need to be applied even to make the F9US suitable for in-space refuelling.

>you would need nuclear fusion level of cheap electricity
Solar electricity is going to become extremely cheap. More energy from sunlight falls on the Earth every single day than has been released by all of the fossil fuels we've ever burned, and everything we count as "proven reserves" in the ground. Solar has been quietly following the typical trend of semiconductor technology, halving in cost to provide the same function at regular intervals. Joule for joule it beats coal now, in the best locations, and it's not going to stop halving in cost any time soon.

>That's just where they'd stop airbreathing flight.

Which is the point where having a fancy sabre engine ends, and now you have a ton of dead weight + low T/W rocket
They'll NEVER recoup the billions of dollars spent on the Sabre project.

>Will moon landing deniers finally shut the fuck up when we go back?

No, that's not how crazy works.

>Which is the point where having a fancy sabre engine ends
...except it already got you into the upper stratosphere and up to mach 5, which is most of a first stage's job, and part of the point of SABRE is that it can shift to rocket mode and close its inlets to reduce drag and tolerate even higher speeds. Like I said, Falcon 9 stages at about mach 6 on flyback launches. BFR is probably going to stage at mach 6, because it uses a flyback booster, not downrange landing. The value of a lower stage isn't measured only by how much altitude and velocity it gets the upper stage to.

>They'll NEVER recoup the billions of dollars spent on the Sabre project.
Will they also never recoup the billions of dollars it'll take to get BFR flying? The Airbus A380 cost $30 billion to develop. Aerospace R&D is expensive. In ten or twenty years, spaceflight may be as popular as airline travel is now.

A SABRE-based launch vehicle could plausibly compete with BFR in the LEO market, and might have reliability and comfort advantages over VTVL rockets.

>...except it already got you into the upper stratosphere and up to mach 5
And all you had to do was cripple your vehicle with horizontal launch & landing & much higher dry weight due to wings + fancy engine.
Not to mention this is a liquid hydrogen engine, they are now stuck with all the hassles of cryogenic fuels.

>Will they also never recoup the billions of dollars it'll take to get BFR flying?

Yes, they absolutely will recoup the billions
Will SABRE ever be used to launch an actual payload? I highly doubt it. Is Skylon even funded?

SABRE is just one of many space scams that are still around collecting money

>cripple your vehicle
None of these things is "crippling".

>much higher dry weight due to wings + fancy engine.
Well compensated for by the effectively much higher specific impulse, and lack of need for boostback and landing fuel. Remember: wings contribute to specific impulse, they accelerate reaction mass you don't need to carry in the opposite direction to the way you want to go (when you're ascending).

The Skylon concept has a 5% payload fraction, compared to BFR's 3.5%, and that's without the scale advantages of going superheavy or the latest in cutting-edge material science. BFR's structures and engines are as cutting-edge as Skylon's were ever supposed to be, it will depend on achieving unprecedented thrust-to-weight and mass fraction figures to reach anything near the payloads SpaceX is claiming (as well as record specific impulse in a hydrocarbon-fuelled engine).

>Is Skylon even funded?
Not the full concept, but practical development of SABRE is progressing. Last year they got 60 million GBP ($80 million) from the UK government to develop a SABRE prototype by 2020. They also have a DARPA contract for subsystem testing. Their American branch is developing a TSTO vehicle, like what I've been saying they should.

>None of these things is "crippling".
They are cripplying though
A VTVL vehicle only needs to be strong in one direction, a HTHL needs to be able to support its weight in 2 different directions
HTHL sets absolute maximums on the size of the vehicle which is much smaller than optimal for a launch vehicle, it doesn't scale as well.

Wings also increase your drag, they HAVE to have wings because of horizontal takeoff, its not an optimal thing. We are not in an era where the fuel cost is the driver of space costs, talkign about increased specific impulse is irrelevant, unless it comes with other benefits like simplifying the vehicle.

Space shuttle: 2030 tonne lift-off mass, 95 tonne dry-mass orbital stage (825 tonnes on the pad), 27.5 tonne maximum theoretical LEO payload
BFR: 4400 tonne lift-off mass, 85 tonne dry-mass orbital stage (1335 tonnes on the pad), 150 tonne maximum theoretical LEO payload

From the expendable claims, we can see that the reusability-specific hardware (mostly heat shielding and winglets) and deorbit and landing propellant together are about 100 tonnes, but it's not easy to divide that up. We can be reasonably sure the expendable mass of the upper stage is between 65 and 35 tonnes (20 to 50 tonnes of reusability hardware, leaving 80-50 tonnes of propellant), or a ratio between payload and stage dry mass of 4-7:1, whereas that of Falcon 9 with booster flyback is only about 3:1. In other words, they're counting on improving the already-extreme mass fraction of the Falcon 9 upper stage by most of what they need to cover the mass requirement for upper stage reuse.

So it's roughly a two-times scale-up, putting about double the mass into orbit. However, despite having an incorporated tank with all the additional recovery hardware that implies, rather than an expendable drop tank, they kept the vehicle dry mass roughly the same.

You can easily see the concept relies on far superior materials and technology in general. Multiple new, unproven technologies can surprise, delay, and disappoint.

While BFR is a better concept than the shuttle, it may not turn out to be as good as they're currently hoping for. With the shuttle, between finalized concept and realization they were disappointed by the engine performance, engine maintenance requirements, the heat shielding cost, heat shielding durability, heat shielding effectiveness, and the structural mass. There's potential for every one of these things to disappoint in BFR as well, resulting in a vehicle which costs billions to develop but provides comparable per-flight cost and capacity to Falcon Heavy.

>By the way, I was talking about cargo Dragon. NASA's squeamishness about certifying an actual crew vehicle is another story.

Cargo dragon is the same thing, its going up to the ISS which is manned.
Dragon was funded by NASA for NASA use, the amount of control they had over the process is very different to the Falcon 9

Satellites are not magic complex machinery, we had satellites back before we had computers. Sats are expensive because of the jobs they will be required to do, and the duration of their mission

Look at how they will be experimenting with upper stage recovery in the near future, it doesn't magically cost hundreds of millions to make changes to the upper stage.

>A VTVL vehicle only needs to be strong in one direction
Not when it does re-entry sideways, like BFS will.

>HTHL sets absolute maximums on the size of the vehicle
No it doesn't, they scale up almost without limit, getting more and more efficient for the most part, though the shape has to change as you get bigger. The Skylon concept was chosen as a minimum practical size for a SABRE-powered launch vehicle. It can still be scaled way up.

>Wings also increase your drag
...and they give you vastly improved specific impulse for ascent. We've been over this. There are compensations. You can't just point at a drawback and act like that ends the argument. When you do the full analysis, HTHL starts looking pretty good if you get an airbreathing engine like SABRE.

>We are not in an era where the fuel cost is the driver of space costs
We are talking about the transition to such an era: Skylon vs. BFR vs. New Armstrong

It's important to remember as well that HTHL vehicles have a long history of graceful failure, whereas VTVL vehicles tend to fail suddenly and catastrophically.

If you lose thrust during a horizontal takeoff, you don't take off, or you make a hop and then land again. As long as your runway is long enough, you can get out and investigate and fix the problem, and fly again, no harm done. You don't need thrust during a horizontal landing, though if you have it, it gives you even more backup options. Generally there are considerable safety factors, so on a good day you have a glass-smooth perfect landing, and on a bad day, you have a somewhat rough landing. You often can survive crash landings.

This is the advantage of relying on simple, passive structures for lift: they're generally more reliable than the engines. Solid physical objects can mostly be counted on to remain the same shape.

If you lose thrust during a vertical takeoff, you fall back down on the pad and make a huge fireball. Same thing during a vertical landing: if the engines don't work, you just splat.

Achieving airliner-like reliability may be impossible with VTVL rockets for the next several decades, due to the unforgiving failure modes.