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29 minutes ago, Cuky said:

Any of you guys seen this?

 

I have seen part 2 as it was recommended by youtube to me today. It is mostly mocking comments that defended SpaceX. I still have to see part 1 though

Most of the stuff he says is pretty obvious, actually. Starship P2P and hyperloop and the Boring Co. have been pretty well argued (and IMO mostly shown to be either impractical or -- in the case of the Boring Co. -- not revolutionary).

We don't know what SpaceX's true costs are because they are a private company. We only know what they charge, and it's not in their interest to charge less than the market will allow them to charge. So whether they are making a ton of money per launch or whether they are losing money per launch, all we know for sure is that their launch prices appear to be a little bit (but not a lot) lower than other providers.

Propulsive landings of suborbital boosters? Yeah, now proven. Propulsive landings (on earth) from orbital speed? Not proven. At-least-partially propulsive landings on Mars or the moon (though with non-reusable parts)? Proven.

Edited by mikegarrison
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Somebody made a response. I’m not sure what to expect out of this, as most of the claims in the original were just common sense.

 

EDIT: partway through the first installment of the original, they make decent economic arguments but nothing special. They really display their lack of knowledge about rockets and the aerospace niche, and as @mikegarrison said, costs probably are intentionally kept (somewhat) high, because there isn’t a ride to LEO for larger than smallsat scale that can compete with F9 on cost.

Edited by Clamp-o-Tron
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19 minutes ago, mikegarrison said:

We don't know what SpaceX's true costs are because they are a private company. We only know what they charge, and it's not in their interest to charge less than the market will allow them to charge. So whether they are making a ton of money per launch or whether they are losing money per launch, all we know for sure is that their launch prices appear to be a little bit (but not a lot) lower than other providers.

There was that vid (that got pulled) of one of the SpaceX engineers at a conference saying their cost was 28M (? from memory) on a reused F9 launch, all-in.

Obviously they have no reason to have their launches cost any lower than "enough to win the bid," particularly as they get pretty much all the commercial launches as it is, and for government launches, they are doled out between the providers regardless of cost so that the government has options.

Until there is a price competitor, there will be no drop in prices. Of course SpaceX passes any savings on to their Starlink project, and 60 sats for 28M is a good deal. Not sure what a commercial Soyuz costs for oneweb's 36 sats, but even 1M per would be pretty cheap (2X SpaceX cost).

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20 minutes ago, CatastrophicFailure said:

See, now, I halfway wanna cringe my way through crap like this yelling at the screen, but I don’t want to give such creators the benefit of the view clicks. :/

I agree, didn't watch it either. a lot of those video's are made because the creator personally hates elon musk or electric cars..

 

I hear enough about that already, so when i want to watch something i want it to be unbiased, not something made to reinforce negative sentiments.

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21 minutes ago, Flying dutchman said:

I agree, didn't watch it either. a lot of those video's are made because the creator personally hates elon musk or electric cars..

That particular guy mainly likes to debunk bogus science claims.

example:

 

Edited by mikegarrison
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I watched it because I think it would be irresponsible of me not to look at an opposing argument. But that argument seems a little lost in all the making fun of Elon Musk - which might be deserved, but seems out of place. In the rest of it, what he successfully explains is that SpaceX is cheaper, just not 10x cheaper than the Shuttle per kg. He also accuses SpaceX of price dumping due to a USSF contract for FH + extended fairing + vertical integration facility being somewhere around 310m instead of 60m for a Falcon 9, which I don’t think is well-considered. Especially because the vertical integration facility is referred to as “I think which means they want a crane to lift stuff onto the rocket.” A lot of the images and figures he uses are out of date, and a lot of the comparisons he makes aren’t on as equal footing as he tries to make them sound.
 

If it’s meant to convince fans like me that SpaceX is just another launch provider doing nothing worth more attention than the rest of them, I’d say the videos are rather unsuccessful. I tried to ignore the sarcasm as much as possible while making that assessment, but I think it’s also worth mentioning that making fun of people who disagree with you isn’t the best way to convince them of your argument. He comes across as putting everyone who thinks what SpaceX is doing is worthwhile in the same group as those weird billionaire-worship people. He also sure likes to talk about Hyperloop, Boring Company, and Tesla batteries in a video ostensibly about SpaceX.

Edited by RyanRising
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1 minute ago, RyanRising said:

But that argument seems a little lost in all the making fun of Elon Musk

Yeah. Like I said, I've seen a few of this guy's videos. His whole schtick is being really sarcastic as he slices up claims he disagrees with.

I didn't think what he said was necessarily wrong. His biggest stretch was guessing how much SpaceX's costs are. However, most of the guestimates I've seen are that SpaceX needs to get about 10 uses per booster before they really get payback for their reusability. Is that actually true? I don't know.

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3 minutes ago, mikegarrison said:

Yeah. Like I said, I've seen a few of this guy's videos. His whole schtick is being really sarcastic as he slices up claims he disagrees with.

I didn't think what he said was necessarily wrong. His biggest stretch was guessing how much SpaceX's costs are. However, most of the guestimates I've seen are that SpaceX needs to get about 10 uses per booster before they really get payback for their reusability. Is that actually true? I don't know.

I thought the 10 uses per booster was the figure given as what they wanted to be able to do without substantial refurbishment, not the minimum break-even point. Or do those numbers just happen to coincide?

Edited by RyanRising
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1 minute ago, RyanRising said:

I thought the 10 uses per booster was the figure given as what they wanted to be able to do without substantial refurbishment, not the minimum break-even point.

Well, that's probably related.

But I don't know. Neither does this Thunderf00t guy. That's the main problem with his video. He does a few scoping exercises and comes up with a break-even number between 3 and 6 launches. But it's a lot of guessing.

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27 minutes ago, mikegarrison said:

Yeah. Like I said, I've seen a few of this guy's videos. His whole schtick is being really sarcastic as he slices up claims he disagrees with.

I didn't think what he said was necessarily wrong. His biggest stretch was guessing how much SpaceX's costs are. However, most of the guestimates I've seen are that SpaceX needs to get about 10 uses per booster before they really get payback for their reusability. Is that actually true? I don't know.

Think we can say that the margin is not so low they need 10 launches to get profit from reuse. I say that they might get that at the first reuse. 
An launch has lots of other costs in addition to the rocket, you also need to have an new second stage . However reuse save you the cost of the first stage, you have to subtract the cost of recovery and the extra maintenance and testing an used stage need. 
Later will go down with experience. 

Now the main problem with reuse is the development cost of it. Here spacex was very lucky with their falcon 9 who they could modify to be reused as engine was restart-able and designed to be reused, 9 engines let you land on one. 
Finally they then developed  reuse during of normal operations after the first stage was done. 
Pretty much the only rocket capable of this so other has to design new rockets and if you don't launch much that is not economical. 

As for starship, the real technical challenge here is return from orbit and rapid reuse, this has never been done before, the closest is the shuttle. 
However spaceX can repeat the falcon 9 first stage development. Once they know they can get starship into orbit and reliable land superheavy they are in business. 
Starship don't need to successfully land to be viable, With the increased payload capacity launching starlink with starship will be cheaper than falcon 9 and they get to test reentry and landing as an bonus. 

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2 minutes ago, magnemoe said:

Think we can say that the margin is not so low they need 10 launches to get profit from reuse. I say that they might get that at the first reuse. 
An launch has lots of other costs in addition to the rocket, you also need to have an new second stage . However reuse save you the cost of the first stage, you have to subtract the cost of recovery and the extra maintenance and testing an used stage need. 
Later will go down with experience. 

Now the main problem with reuse is the development cost of it. Here spacex was very lucky with their falcon 9 who they could modify to be reused as engine was restart-able and designed to be reused, 9 engines let you land on one. 
Finally they then developed  reuse during of normal operations after the first stage was done. 
Pretty much the only rocket capable of this so other has to design new rockets and if you don't launch much that is not economical. 

As for starship, the real technical challenge here is return from orbit and rapid reuse, this has never been done before, the closest is the shuttle. 
However spaceX can repeat the falcon 9 first stage development. Once they know they can get starship into orbit and reliable land superheavy they are in business. 
Starship don't need to successfully land to be viable, With the increased payload capacity launching starlink with starship will be cheaper than falcon 9 and they get to test reentry and landing as an bonus. 

I think Starship will probably be expensive enough that expending it won't be cheaper than a F9 launch. There's a lot of hardware and work hours that will go into a full-up orbital Starship, and it's a significantly more complex beast than a F9 second stage. That being said, I absolutely think that they'll put Starlink sats on the first couple orbital launches and reentry tests. You're going to orbit anyway, why not put something up there?

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18 minutes ago, magnemoe said:

Think we can say that the margin is not so low they need 10 launches to get profit from reuse. I say that they might get that at the first reuse.

Wait, what? That seems really unlikely. There are a lot of parts of a Falcon9 booster that are only the way they are because of the desire for reuse. I have no doubt that it is significantly more expensive than a disposable booster would be, and all those parts need to get "bought" by cost savings on reuse. I don't think a single reuse would be enough to break even versus a disposable rocket.

18 minutes ago, magnemoe said:

Starship don't need to successfully land to be viable, With the increased payload capacity launching starlink with starship will be cheaper than falcon 9 and they get to test reentry and landing as an bonus. 

That also seems completely wrong to me. There is no way a Starship is cheaper than a one-time disposable second stage. No way. And the numbers SpaceX was tossing around for being cheaper than Falcon9 per ton were dependent on full reuse of both stages.

Edited by mikegarrison
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Regarding reuse, the cost associated with reusable vs expendable for F9 seems pretty marginal, at least on the vehicle.

Grid fins, and legs. Now fairing hardware, too, I suppose (added thrusters and chutes).

Merlin evolved anyway, increasing margin. That would happen regardless. F9 as a system has so much margin that reuse is not a performance issue except maybe on Starlink launches—the only ones that come close to maxing out payload, and they're almost 10 tons short of F9 payload to LEO with very little remaining room in the fairing.

Off the vehicle, obviously recovery vessels, etc are a substantial expense.

At the point that one SpaceX guy said 28M/launch, I'm not even sure they were recovering fairings. I also have to assume whoever buys a launch pays for the entire vehicle unless they somehow are selling launches for the first flight at a loss, which seems pretty unlikely. Also, there's Starlink, seems bizarre to not make an expendable vehicle if that was actually cheaper.

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5 hours ago, mikegarrison said:

That also seems completely wrong to me. There is no way a Starship is cheaper than a one-time disposable second stage. No way. And the numbers SpaceX was tossing around for being cheaper than Falcon9 per ton were dependent on full reuse of both stages.

? Launching it could be, assuming it works.

Assume the booster works like F9, so that's reused, and with less refurb. SS itself vs the F9 S2 is the hardware and prop cost of the F9S2 vs the prop cost of SS. What does 1200t of CH4 and LOX cost? That seems to be the math they are doing (we'll have to see if the thing actually works at all, then see if it is actually "rapidly reusable."

I think in the long term Musk is right that "rapid reuse" is required for a "spacefaring" society to be a thing. Phil Bono said as much in the 60s. Getting to that point of course is the hard bit.

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5 hours ago, mikegarrison said:

Wait, what? That seems really unlikely. There are a lot of parts of a Falcon9 booster that are only the way they are because of the desire for reuse. I have no doubt that it is significantly more expensive than a disposable booster would be, and all those parts need to get "bought" by cost savings on reuse. I don't think a single reuse would be enough to break even versus a disposable rocket.

That also seems completely wrong to me. There is no way a Starship is cheaper than a one-time disposable second stage. No way. And the numbers SpaceX was tossing around for being cheaper than Falcon9 per ton were dependent on full reuse of both stages.

The grind fins are pretty expensive, legs also cost some, however just a fraction of that an full stage and with reuse they can be used multiple times, even reused if stage is scraped or disposed. 
Also I implied the cost of recovery and republish 2 times is cost less than an disposable first stage, the launch itself all the testing they do anyway and the second stage adds to the cost. 
 

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