NASAs lift problem

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#52
but i've seen the possible upgrades on J-2 engines (Aerospike J-2 engine)
 

Horus Lupercal

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#53
Apollo 4 leaves the Cape, 9th November, 1967

s67-49969-1548369328.jpg


“That Saturn 1C stage, with those five F-1 engines, is a massive piece of hardware," said Lee Solid, a Rocketdyne senior executive that worked on the program. “If that sucker was going to blow, it was not only going to take itself and the whole vehicle, but it was going to take the launch pad and most everything halfway back to the firing room in the explosion.

"Luckily, that never happened.”


"At liftoff, the vibration from the Saturn V showered us with dust and debris from the ceiling of the Launch Control Center, which was brand new at the time," said NASA's public information chief Jack King, who served as the countdown commentator for the launch.

Dr. Hans Greune, director of Kennedy Launch Vehicle Operations, worried that the massive Vertical Assembly Building that once housed the rocket might crack under the immense release of sound and energy.


https://www.popularmechanics.com/space/rockets/a26013658/saturn-v-rocket-wernher-von-braun/
 

Anoki

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#54
The five engines themselves produced 220 decibels. That's enough to melt concrete a few feet away.
According to a user on Reddit who was referenced in an article (I'm gonna take a dumb risk and trust this guy):
"At 500 meters [from the launch pad], at 155 db you would experience painful, violent shaking in your entire body, you would feel compressed, as though deep underwater. Your vision would blur, breathing would be very difficult, your eardrums are obviously a lost cause, even with advanced active noise cancelling protection you could experience permanent damage. This is the sort of sound level aircraft mechanics sometimes experience for short periods of time. Almost twice as “loud” as putting your ear up to the exhaust of a formula 1 car. The air temperature would drop significantly, perhaps 10-25 degrees F, becoming suddenly cold because of the air being so violently stretched and moved."
That's five football fields away.
 

Zeeray13

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#55
And by expandable, I think we mean the booster. Because if the second stage can get to orbit without enough margin to come back, it can be refueled to provide that margin.
There is 2 configurations 1 with a 37 raptor on the super heavy LV (the booster) or 31 I believe. They also plan on making 2 sizes the one we are getting is baby Starship and the other is Daddy Starship
 

Zeeray13

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#57
Boeing may make 'shit' space craft. But they make much better airliners than SpaceX. And that is the bit that's going to screw a lot of people over if it goes under. Airbus may make better (apparently) so they'll likely fill the vacuum of airliner numbers, but not the number of people out of work on another continent.
I would disagree on the better airlines. At least as of late. Both the Dreamliner and 737 Max were great on paper their launch both had problems and the 737 with far more of them. Boeing as of late isnt the same company that made the 747 or 777. It went through a shift in ideology that now makes it more of a company that cares about share holders and raising the stock price. With that came a cut in quality, as well as employee respect. Also Airbus has always been behind but they have managed time and time again to release something that is competitive if not better then Boeing that's why people say Airbus is better. Anyways BOT Boeing does make shit spacecraft.
 

Zeeray13

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#58
Also i like the goal Horus Lupercal to stay away from politics on this one, the sad truth is you can't get away from something that was made in politics. You especially can't avoid it when talking to any American as the veiw is political in nature 99% of the time. So what do I think. Scrap both SLS and that reborn Saturn V idea put the funds towards companies like spaceX and a company I hate Blue Origin. Why I say that is they are far more efficient and less caught up in the thing that is killing SLS and killed the Saturn V. NASA still is useful though and can use some of that money elsewhere anyways. With cheaper launch providers due to competition and full reusability can launch whatever they need. Yes launches are more complex, but guess what have we sat on our ass completely for the last 50 years? No not even NASA has. You ignore one of the reasons why the Saturn V was made it was more simple and they didn't have the technology to do what we can today. Yes they could orbital rendezvous but it was alot harder and things did and could go wrong. I think the Saturn V was the right tool at the right time. Now we have better tools and we should start using them rather then trying to reuse old ones that yes might work, but have really no practical purpose. You wonder why Delta-IV is never launched and Falcon Heavy has only launch 3 times that payload requirement isn't really needed. Starship is going to be ready within 2 to 3 years to do regular flights. Anyways in summary scrap SLS start giving grants to private companies and any extra money should be used to start launching those fancy spacecraft that NASA like to send all over the place.
 

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#59
I would disagree on the better airlines
You would? Do you know of some super awesome airliner that SpaceX have made that I don't? I wasn't aware SpaceX were even in the aero industry, but you learn something new every day I suppose.


Airbus has always been behind, but they have managed time and time again to release something that is competitive, if not better then Boeing. That's why people say Airbus is better
Erm...you've managed to go from 'Airbus always behind' to 'Airbus are better (thus ahead)' inside one sentence. Also, my point wasn't about which out of Airbus or Boeing made the best airliners. Both are going down the shitter at the moment anyway.
My point was the job losses if Boeing went under. We wouldn't lose out on aircraft to take us on holiday as someone will fill that niche, but there'd be a lot of Americans trying to find alternative employment that won't be able to work at Airbus cos they're based on another continent.
Congress is looking at Boeings trashed financial year, that the 737 Max has imploded, the 787 is heading for an early shower, they've just shitcanned support for the 747 fleet (They scrap airliners next door to me, and there are atleast 4x 747s here waiting to be cut up), Virgin, Qantas and BA have basically retired their fleets overnight and aside from giving them money for the 'new' F-15EX programme, cancelling SLS would all but kill the company. And what they don't want is what happened when GM went under and Detroit went from 'Motor City' to the set of Robocop.
Because even though it costs 20 billion dollars, it's 20 billion spent in the US.


the sad truth is you can't get away from something that was made in politics. You especially can't avoid it when talking to any American as the view is political in nature 99% of the time.
You can. Because you just did. You managed to make an entire paragraph and didn't mention politics (be it 2 party, NASA vs SpaceX or whatever). It can be done. We just need to convince the other 350 million of you to follow suit.

Although I will say this. Jesus man, I wish you'd use the return key every once in a while. Makes finding my place so much easier when things are in paragraphs and I don't have to read the entire thing to figure out where I was.


Scrap both SLS and that reborn Saturn V idea. Put the funds towards companies like SpaceX and (a company I hate) Blue Origin
I agree with 3/4s of that. The SLS needs to die. And yeah, throwing that 9.1 20+bn dollars they've wasted on SLS at Space X/Blue Origin/ULA/into the fucking ocean would've made a much better output.
However, Saturn 2021 isn't as bad an idea as you're making out later on. Your conclusions are flawed. The reason why Saturn 2021 is viable is for the same reason why SpaceX are building Starship. More on that later.


NASA still is useful though and can use some of that money elsewhere anyways
Absolutely. NASA does an absolute metric shitton of work behind the scenes beyond rockets and I agree, pushing resources away from SLS and more towards NASAs other outputs that it really has no equal in, particularly in the US, would be much better for NASA and everyone else as well.


With cheaper launch providers due to competition and full partial reusability can launch whatever they need
Not yet they can't. As I've said, a lot of the infrastructure that NASA the world needs to put into orbit if it wants to go to the moon (or further afield) with more than 3 guys and bring more than a few rocks back in ziploc bags can't be lifted using the cheaper, partially re-useable launch systems currently in service with SpaceX etc.
That fact is the only thing keeping SLS in business and is the main reason why I say you're wrong about heavy lift rockets having no place in the world right now (Saturn in particular). The heavy/super-heavy lift concept isn't out-dated. It's waiting for its time to come.
And until Starship gets off the ground as more than a rocket assisted grain silo, Saturn V is still the most capable and cheapest (the irony) super-heavy launch system anywhere in the world.


but guess what, have we sat on our ass completely for the last 50 years?
Pretty much, yeah. NASA has lost a 50 year lead to a guy who was almost bankrupt a few years ago and despite raiding the back catalogue for anything that works, has had to piggy back a ride from him to the space station it's about to abandon (again) and will still be beaten to space by him in the one category that NASA has always maintained was its exclusive capability. More on that later as well.
I love the way NASA has spun the Crew Dragon thing, trying to make it look like there was a chance it wasn't going to use SpaceX for manned missions to the ISS.
As if they had much fucking choice in the matter. Either they bankroll Elon or they continue bankrolling the Russians, but they weren't getting there themselves.


You ignore one of the reasons why the Saturn V was made. It was more simple and they didn't have the technology to do what we can today
I understand entirely why Saturn was made and why it was made like it was. It was made that way because the US of A were using a 111m tall stack of Top Trumps cards to brute force themselves to the Moon before the USSR, regardless of cost.
Not because it was simple. Under no spotlight and by no comparison can the Saturn V be called a simple thing. Even today, it's still one of the most complex moving objects ever created by the hands of Man, beaten out of that accolade only by things like the Space Shuttle and the ISS that it was used to build.
You confuse complexity with having lots of computer power. Falcon is a (comparatively) very, very simple piece of hardware with a shitload of software controlling it. Saturn V is a nearly 3,000ton version of the house from Home Alone, a huge analogue clockwork monster with 3 guys strapped to the top of a 2.9kt bomb being operated using physical wires.
Hell, that's always been the problem with Saturn. It's too complex for its own good which is why it was so damn expensive to build. Granted, it was made that way because of the limitations of the 60s, but if they made it today, it wouldn't get more complicated. As I've pointed out before, the engines alone would lose 60% of their total part count (and complexity) under a 2020 build scheme.

Saturn V was also made the way it was because NASA built it from the payload mission statement down. Unlike what it is doing now, where it is trying to make the mission fit the launchers (make me the most efficient rocket plz), 1960s NASA created the Saturn to move its Apollo / Skylab program.
Obviously there was a bit of the rocket determining how much Apollo / Skylab could weigh, but not as much as it is with SLS / Falcon Heavy etc where the rocket designs have been finalised and are in production but Artemis is still having the basic concept hammered out on a drawing board (They've only just figured out which designer they're going for) and are still working out if they're going for an LEO RV, how many lifts they're going to need to do before TLI, who is going to be lifting what component, is there going to be a Gateway stop off, are they doing a lunar RV or a one piece lander etc.
Remember, if Apollo or its follow up had needed to be a lot heavier, Saturn wasn't anywhere near its maximum capabilities. They could always have pushed more with a little modification (the MLV program).
SLS Block II with the advanced SRBs is it. NASA have no 'plan B' for lifting more weight per single launch. So if they need to put a 140+ton object into space, it means breaking that object in half and throwing 2x 2.1 billion dollar rockets into the sea rather than doing up to 200t with a single stretched Saturn V MLV.
'But what weighs 140+ to 200t Horus?! No payload needs to be that heavy in the real world'. I'll tell you what does.
Manned Moon missions. Manned Mars missions. Future asteroid re-direct and mining missions, automated or not.


Now we have better tools
We do? Like what? SLS? Falcon Heavy? Delta IV Heavy? Falcon Heavy is better at Falcon Heavy things than Saturn V. I've never said otherwise. But at Saturn V things (lifting really heavy stuff), Saturn buries FH / D4H / SLS at everything except cost. And like I've also said before, they're not factoring in cost when it comes to these big Mars/Moon missions. They've spunked 20 billion dollars into an obsolete launch system because they have one criteria that over-rides all others.
They need mass lifted to space regardless of cost.
And as I've said many times now, until Starship flies, nothing lifts more mass than Saturn.

And I'll keep saying this as well.
Saturn V is still the only flight proven, human rated, moon capable rocket in existence. There are no better tools, because no other tools yet exist.


we should start using them rather then trying to reuse old ones that yes might work
Why not use the rockets that are proven to work? If it isn't broke, why fix it? And 'because newer' isn't a valid argument. Give me a capability jump, a safety stat increase, something objective rather than something akin to the reasoning why you'd buy the latest iPhone rather than keeping the one you got that works just fine and does exactly the same job.


but have really no practical purpose
OOooohhh, critical error made there mate. Observe.


but have really no practical purpose. You wonder why Delta-IV has never launched and Falcon Heavy has only launched 3 times? Because that payload requirement isn't really needed. Starship is going to be ready within 2 to 3 years to do regular flights
You've contradicted yourself inside of a single sentence again. Heavy and superheavy lift rockets have no practical purpose. Except Starship, the most super of superheavy launch systems, which will have a practical, regular purpose. You can't have both sides dude.
Either we need super-heavy lift, or we don't. So the same reason to scrap an SLS / a modern Saturn / FH / D4H you mentioned (the payload capacity isn't needed) is the same reason why they should just sack Starship now and concentrate on F9. Or, the reason why Starship is going to be so awesome in future (its payload capacity, which will be needed) is exactly the same reason why a modernised Saturn V has/had a role.

Also, are we thinking about different Delta 4 Heavies? Delta IV Heavy has been flying since 2004 dude. It put the Parker Solar probe up (using that high payload lift ability to throw a 500kg object at the sun). Hell, they had an on pad abort on one 2 weeks ago.
 

Horus Lupercal

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#60
Anyways in summary, scrap SLS
It seems that even the biggest supporter of SLS quietly agrees with you.

https://arstechnica.com/science/202...nistrator-says-sls-rocket-will-go-away/?amp=1

My favourite quote is this one.

If you're wondering what commercial space proponents really think about the SLS rocket due to its cost and expendability, it's this, which comes from a senior official at a new space company:

"If Santa Claus arrived, and said, 'I have good news. It now works and you can launch tomorrow. Everything's done. You're going to have a launch tomorrow.' ... It still isn't getting us to the Moon. Even if they achieve everything they aim for, it still does not get people to the Moon. It certainly does not get a base on the Moon and absolutely doesn't get humans to Mars."


I'll put money that 'senior official' works at SpaceX.

There are only 2 rockets that are capable of a realistic moon landing that ever got off a drawing board. One of which (until very recently) held the distinction as the largest non - nuclear explosion in history.

Neither of those are SLS. NASA has a lift problem, and will do for the foreseeable future.
 

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#61
It seems that even the biggest supporter of SLS quietly agrees with you.

https://arstechnica.com/science/202...nistrator-says-sls-rocket-will-go-away/?amp=1

My favourite quote is this one.

If you're wondering what commercial space proponents really think about the SLS rocket due to its cost and expendability, it's this, which comes from a senior official at a new space company:

"If Santa Claus arrived, and said, 'I have good news. It now works and you can launch tomorrow. Everything's done. You're going to have a launch tomorrow.' ... It still isn't getting us to the Moon. Even if they achieve everything they aim for, it still does not get people to the Moon. It certainly does not get a base on the Moon and absolutely doesn't get humans to Mars."


I'll put money that 'senior official' works at SpaceX.

There are only 2 rockets that are capable of a realistic moon landing that ever got off a drawing board. One of which (until very recently) held the distinction as the largest non - nuclear explosion in history.

Neither of those are SLS. NASA has a lift problem, and will do for the foreseeable future.
Interesting that former NASA administrator said in 2014:
Charles Bolden said:
"Let's be very honest again," Bolden said in a 2014 interview. "We don't have a commercially available heavy lift vehicle. Falcon 9 Heavy may someday come about. It's on the drawing board right now. SLS is real. You've seen it down at Michoud. We're building the core stage. We have all the engines done, ready to be put on the test stand at Stennis... I don't see any hardware for a Falcon 9 Heavy, except that he's going to take three Falcon 9s and put them together and that becomes the Heavy. It's not that easy in rocketry."
And then this year:
Charles Bolden said:
“SLS will go away," he said. "It could go away during a Biden administration or a next Trump administration… because at some point commercial entities are going to catch up. They are really going to build a heavy lift launch vehicle sort of like SLS that they will be able to fly for a much cheaper price than NASA can do SLS. That’s just the way it works.”
I don't think he's 100% converted, he still isn't saying that falcon heavy could do what SLS was supposed to do.:D
 

Roger Jolly

Veteran Astronaut
#62
I hear an upgraded crew dragon could be launched separately from a Moon lander with falcon heavies if I got that right, no reason those have to be launched together, safer even by putting up the lander separately

Boeing needs a mad CEO to tear that old barn down Amish style rebuild it clean, or just burn the whole mess down and forget it;
Congressional cowardice/corruption is the problem, quit paying a broke ass company to do shit ass work...find new contractors

There ain’t no damn astronauts going to Mars with any current capability, we don’t even have a laundry system much less food, radiation protection, the atrophy problem, space madness, backup plan or anything...Mars 2030 makes me laugh, it’ll take dozens of huge supply launches just to prepare, the actual ‘hab tech’ is nonexistent

The Moon is awesome, so much to do there, so much to learn
 

Mooncrasher

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#63
As far as I can find out, Falcon heavy could carry the Apollo CSM to LEO. Another falcon launch to bring up the LM, that just leaves the question of how to bring up the TLI stage, and the astronauts (probably Falcon crew dragon).
My idea is to bring the astronauts up in a crew dragon atop another falcon heavy, transfer them over to the CSM and send the dragon home, and use the mostly-full second stage from that crew launch as your TLI stage.
Probably only works in kerbal spaceflight program, but if I can think of a possibility, someone smarter than me could think of a possibility that works.

Point is, you don't even need SLS in order to do what Saturn V did.
I know Apollo wasn't designed to be assembled in LEO by a falcon heavy-class rocket, but it could have been, as far as I can tell.
Skylab wouldn't have been as impressive with a falcon heavy, but I'm sure it's possible to make a cool space station with the cheap kg to orbit that the falcon heavy offers.
 

Blazer Ayanami

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#64
Interesting that former NASA administrator said in 2014:


And then this year:

I don't think he's 100% converted, he still isn't saying that falcon heavy could do what SLS was supposed to do.:D
At least the has begun to change his mind, at least now he is saying SLS will go away :D
 

Horus Lupercal

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#65
As far as I can find out, Falcon heavy could carry the Apollo CSM to LEO. Another falcon launch to bring up the LM, that just leaves the question of how to bring up the TLI stage, and the astronauts (probably Falcon crew dragon).
The concept will please Wernher at least. He always wanted an orbital RV scenario.


My idea is to bring the astronauts up in a crew dragon atop another falcon heavy, transfer them over to the CSM and send the dragon home
Works fine, as the docking area on top of the CSM will still be free at this point to park the Crew Dragon onto and then have it fly itself home.

The big problem is this:

and use the mostly-full second stage from that crew launch as your TLI stage.
It won't work. Allow me to explain why.

A fully disposable Falcon heavy can lift 63tons to LEO. Which is plenty enough for either the LM/CSM or even both (all up, the Apollo spacecraft minus the TLI stage weighed 44 tons [28 for the CSM, 15 for the LM]). Or you can punt them up individually on re-useable FH flights (30tons maximum capacity). So that side is fine.
A Crew Dragon weighs 15.5 tons (9.5 dry, 6t of payload stores, crew and manoeuvring propellant). That means if you want a 'nearly full' second stage of the FH once you hit LEO, then you're going to need to bin the remainder of the rocket, otherwise you'll be at roughly 50% fuel instead.

Then comes the next problem, which is Trans Lunar Injection itself.

According to NASA,

How To Send A Space Shuttle To The Moon 1.jpg


TLI requires 3048m/s of dv. That's not including a capture burn, that's just getting there. This required 140,000lbs (63.5tons) of propellant back in 1969, using the single J-2 engine attached to the S-IV stage of the Saturn V.

So, I did a bit of digging. What would it take for a SpaceX created, Merlin -D powered TLI stage to get to the Moon with an Apollo sized payload?

This wasn't too difficult, SpaceX is pretty open about what their kit can do, though I ran the numbers and either the mass or the thrust of the Merlin D vacuum is utter, utter bullshit or it's the greatest engine ever conceived, because it apparently has a TWR of over 200. For context, the F-1 only has a TWR of 94.1 and the J-2 has 58.9.

Anyway, to the comparison.

For this, both engines are powered by the same fuel (SFS Liquid Fuel), which makes life easier cos I don't have to mess around with converting the correct ratio of fuel mix from LH2 to RP-1 because of their separate densities. In reality, both are liquid engines engines, but one is RP-1 and the other is LH2. If there is a huge difference (I'm aware fully that the RP-1 that Merlin uses is heavier per m3 than LH2, but my understanding is that just means that you need more tank space, not more actual propellant mass using LH2 like the J-2 does), then I'm more than content for someone with more knowledge of the fuels to adjust to suit.

Next, since I have no idea what the mass ratio of NASA or SpaceX tankage is, I decided to use a single, known and simple ratio. Spaceflight Simulator, which uses a 1:10 tank to fuel mass ratio for its version of tankage to keep it as level as possible, take the fuel tank and building techniques (common bulkhead vs friction stir welding) out of the question and use one standard to calculate the fuel requirements needed.

What I did first was ran the J-2 engine at vacuum rating (421sec isp) with an Apollo mission weight (44tons for the LM/CSM. Again, I'm aware that not all Apollo missions were created equally and Apollo 17 came in at around 48.4 tons, Saturn Vs maximum 'to the moon' payload capacity) through the system, and came out with a 63 ton TLI stage mass weight (tank and fuel complete) for a total requirement to LEO of 109 tons (payload, fuel and engines).

Then it was the turn of the vacuum version of the Merlin -D, under the same test conditions. Merlin - D has (according to SpaceX) a specific impulse of 348 seconds. This needs 85t of fuel and tankage with an all up to LEO requirement of 129 tons.

Obviously these tank weights aren't going to be exact. There are a lot of variables with the tank design and sizes (for example, an LH2 tank would need 3 times the volume, which is a larger tank and higher dry mass/mass ratio compared to RP-1) which is beyond my knowledge to factor in.

Again, more than happy to be corrected or the numbers made more accurate, but unless the numbers change significantly then it's going to take a lot more propellant mass to move a SpaceX powered 2021 NASA/Artemis mission than an 1969 NASA/Apollo mission.

What that means then is thus.

Falcon Heavy could do a fair amount of the Artemis mission to LEO. But it doesn't have the capability to lift the 3048m/s of propellant needed for a Merlin powered, Apollo/Artemis mass TLI stage. For that, you are gonna need a super-heavy lift launch system. SLS, Saturn V or Starship.
 

Horus Lupercal

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#69
Skylab wouldn't have been as impressive with a falcon heavy, but I'm sure it's possible to make a cool space station with the cheap kg to orbit that the falcon heavy offers
Skylab at 140 tons, remains the single heaviest object thrown into orbit. Falcon Heavy couldn't lift a quarter of Skylab if you wanted the rocket back.
If you were to use FH to punt a 'one shot' space station into LEO, it'd have to be a 'wet' station, like the concepts for Skylab when they were going to use Saturn IB for the project instead of the Saturn V.

The second stage of Falcon (according to SpaceX literature) is pretty maneuverable, and Crew Dragon can dock itself autonomously. However, I'd be skeptical if anyone allowed a space station, lifted in sections by multiple launches, to assemble itself in LEO without a human presence to verify it.
So, launch some humans up in a Crew Dragon to oversee and do the space walks which is possibly be the only option at this stage.
Send up a fully manned crew dragon on an F9. You've then got a few days of solo 'loiter' time whilst the CD is upstairs to then throw up the first section by Falcon Heavy which needs to have some kind of module manipulation system like Canadarm, an orbital maneuver system so it doesn't de-orbit or bang into something during the waiting time and somewhere to dock the CD onto to supply it and extend its orbital lifespan whilst the crew supervise assembly.
You can then either launch the modules within the next 3 months or so, keeping the same CD team up there, or spread the launches out and bring the dragon back between each one and re-launch a separate crew up just before each module arrives.
 

Mooncrasher

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#70
Skylab at 140 tons, remains the single heaviest object thrown into orbit. Falcon Heavy couldn't lift a quarter of Skylab if you wanted the rocket back.
If you were to use FH to punt a 'one shot' space station into LEO, it'd have to be a 'wet' station, like the concepts for Skylab when they were going to use Saturn IB for the project instead of the Saturn V.

The second stage of Falcon (according to SpaceX literature) is pretty maneuverable, and Crew Dragon can dock itself autonomously. However, I'd be skeptical if anyone allowed a space station, lifted in sections by multiple launches, to assemble itself in LEO without a human presence to verify it.
So, launch some humans up in a Crew Dragon to oversee and do the space walks which is possibly be the only option at this stage.
Send up a fully manned crew dragon on an F9. You've then got a few days of solo 'loiter' time whilst the CD is upstairs to then throw up the first section by Falcon Heavy which needs to have some kind of module manipulation system like Canadarm, an orbital maneuver system so it doesn't de-orbit or bang into something during the waiting time and somewhere to dock the CD onto to supply it and extend its orbital lifespan whilst the crew supervise assembly.
You can then either launch the modules within the next 3 months or so, keeping the same CD team up there, or spread the launches out and bring the dragon back between each one and re-launch a separate crew up just before each module arrives.
And your only disposable lifting hardware is the falcon second stage at maybe $5 million a pop.
This sounds cheap and eminently plausible.