Author Topic: Would it have been a good idea for FH to be like Angara (i.e. 5-core)?  (Read 24611 times)

Offline a_godumov

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As a KSP player I would say that KSP indeed tends to popularize very complex designs with lots of staging events and multiple cores. The reason for this is that the game simply cannot simulate all factors and all variables. One of my favorite rockets I've built is an asparagus staging design with 6 boosters each outer booster crossfeeding to the inner booster next to it and the final 2 inner boosters crossfeeding the core. As a result upon each of the 3 staging events the boosters have full tanks and of course I have an upper stage on top of that.

This design maximizes my payload but I don't think such a design would be workable in real life due to the complexity (both in the multiple staging events and also in the vehicle processing and the requirements for a special pad) and the added risk of the multiple staging events. In the case of the Falcon rocket such a design would also increase complexity by requiring multiple landing pads and/or landing drone ships.

In real life a tradeoff has to be made between the efficiency and performance of the vehicle and its complexity. SpaceX's goal is to minimize the costs per kg to orbit, not to create the highest performance or most efficient vehicle.

In this specific case Angara seems to be hoping to decrease the price per Kg to orbit by using effeciencies of scale and also by building multiple variations of the rocket using common components (their ad videos almost make it look like Lego) while SpaceX hopes to decrease the price per Kg to orbit by accomplishing practical reuse with minimal refurbishment. If they succeed it makes sense to avoid more complex designs because in such a case human labor will become a very substantial part of their costs (it actually is even now) and having to refurbish and stack multiple boosters will certainly require a lot more labor. If both Falcon 9 and Angara accomplish their goals I guess in the long term an Angara rocket may end up cheaper than a Falcon 9 to build but a Falcon 9 can be reused multiple times.
« Last Edit: 06/12/2016 06:53 PM by a_godumov »

Offline Pipcard

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This design maximizes my payload but I don't think such a design would be workable in real life due to the complexity (both in the multiple staging events and also in the vehicle processing and the requirements for a special pad) and the added risk of the multiple staging events. In the case of the Falcon rocket such a design would also increase complexity by requiring multiple landing pads and/or landing drone ships.
In addition to him believing that multiple staging events (because Soyuz can be reliable with 4 LRBs) or processing (because "economies of scale") weren't an issue, he thought multiple barges or pads weren't a big deal either.
Quote
In practice, you would probably have 4 barges, all for landing. Those barges aren't that expensive, compared to the rocket. :P And the landing pad at the cape has 5 landing pads anyways. :P

If they succeed it makes sense to avoid more complex designs because in such a case human labor will become a very substantial part of their costs (it actually is even now) and having to refurbish and stack multiple boosters will certainly require a lot more labor.
I'm guessing fredinno rather thinks that the same amount of labor/machinery required to process a single core could be split up to process multiple smaller cores, while gaining the "economies of scale."
« Last Edit: 06/12/2016 07:13 PM by Pipcard »

Online NaN

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So to the OP - F5 is too small, drives too many payloads to 3 or 5 boosters, and the processing costs/time are too high for the potential, unproven gains of less engine use (and there might be more engine use due to flying payloads on 3 or 5 boosters that would have flown on 1!).

When I look at the manifest, the OP suggestion would have a) required cluster operation earlier and b) been more costly/risky. So the F5 to F9 original decision was the right one.

He said
Quote
And a what's easier to maintain, a single large booster, or 5 smaller ones? I would state the latter, since it allows for economies of scale, and use of machines to maintain the boosters.

Then why stop at 5? The inescapable conclusion is that you should go full OTRAG. Also, it should be expendable because STS 'proved' that the more you reuse, the more it costs.
More seriously: there is no fundamental principle which says that fewer boost cores, or fewer stages, or fewer configurations is always better, so there is no way to prove it - it is better with all else being equal, and all else is never equal in engineering. Pointing to real-world examples is (imo) very fraught because success of real-world examples are dominated as much by investment level and heritage as by any superiority of the configuration. If somebody is just trying to win an argument on the Internet, it's easy to ask for proof that fewer cores is better and then claim victory when you fail to provide it - and if you're not worried about real-world practicalities of the sort that Space Ghost raises, then designing rockets is easy. KSP does encourage this sort of thinking because it's trivial to, for example, slap on a fuel pipe anywhere you need it and get asparagus staging FTW.


Offline Saabstory88

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To introduce an even more practical limitation to this speculation,

- Launch Hold-Downs
- GSE connections

Find an arrangement where that works with 5 cores. Bear in mind, the connections shown on the website model are not accurate, the wind tunnel model shows how complex these connections will really be.

Offline Pipcard

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I also tried explaining to fredinno the idea of having an oversized monolithic reusable rocket launching all payloads (like what is being talked about in BFR speculation threads), and the very reason why SpaceX is only using Falcon 9 with the retirement of Falcon 1, and he had a lot to say about that (bolded for emphasis):

Quote from: fredinno
[image macro of Han Solo captioned 'That's not how it works / That's not how any of this works']

 Just because you can launch everything on one rocket, doesn't mean you should. Even for a fully reusable rocket, a single 29T rocket (if the rocket is full CH4 or RP-1, a rocket with a H2 2nd stage can settle for a lower LEO payload capacity, like 25T to LEO, due to superior GTO capacity)
[I don't know why he's assuming a 25-29 tonne rocket. Falcon 9 FT is all RP-1 and has an expendable capacity of 23 tonnes]

Let's use the IXV example again [launching on a 29-tonne rocket]. How in the WORLD would you give it secondary payloads? It would be a 1-2T payload on a rocket designed for 29x its payload capacity. Assuming full reuse, you still have to build a rocket every ~10 flights, and the massive rockets are harder to maintain (w/ F-1 sized engines).

Reuse doesn't remove costs. It only saves optimistically 40% in cost (both stages). The rest of the cost structure, like testing and inspection, get larger- testing a larger engine of a TSTO RLV is more expensive. It also increases the complexity and integration costs you seem to be so worried about, since deploying 10 satellites is more complex than orbiting one, and larger rockets are more complex and difficult to develop.

Not to mention, satellite companies WANT to be able to choose where they go, instead of being dropped in a compromise orbit that needs to be shared with 50 other satellites. That's why smallsat launchers are taking off, even though it is more expensive. Hell, companies will sometimes buy entire Ariane 5s just for one payload just for that reason. (However, for GTO, launching 2 satellites is far more economical, since all the satellites are in roughly the same orbit. LEO sats practically require dedicated rockets.)

Thus, you will go through those rockets much faster than normal- and the reuse will make it difficult to achieve mass-production anyways, producing 3 a year, assuming a 30x a year launch rate. A planetary probe launch that year would leave you producing 4 a year. :P

Meanwhile, a reusable Angara solution allows you to produce ~15 cores a year with reuse and a 30x per year launch rate, much closer to mass-production, and optimize for any payload with little development cost (depending on what satellites you launch that year).

[me: Thus, the fully reusable BFR could replace the F9/FH family once it's operational. Multi-purpose, not only for Mars. And using the same monolithic fully reusable launcher for all payloads also ups its flight rate.]

LOLWUT

Imagine launching an SLS to launch IXV :D

You make me chuckle. You probably could use the SLS core as a reusable SSTO and launch IXV!

On a serious note, who would do that? I can't see SpaceX spending 500 Million dollars making a rocket, only to then launch 5T satellites. That would cost mare than any F9.

It seems similar to the attitude that the Shuttle would reduce costs to launch, and everything should launch on it, because it was 50% reusable (including the "reusable" SRBs), even though it needed every single launch it could possibly get to break even with commercial launchers.

There's that "mass production vs reusability" issue again. He seems to be making valid points, and we can't seem to completely convince each other, so which launch vehicle architecture makes more sense?

(I've also invited him to join the discussion here.)
« Last Edit: 06/13/2016 06:56 AM by Pipcard »

Offline gospacex

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You reached a point in discussion where you circle each other ad nauseum. You may as well agree to disagree.

Final test of these ideas is practice, as always.

Online JamesH65

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You reached a point in discussion where you circle each other ad nauseum. You may as well agree to disagree.

Final test of these ideas is practice, as always.

Quite. Since there is currently no evidence one way or the other, until we have reusable FH's and a reusable design like the Angara to compare, the argument is going nowhere. I doubt anyone here or elsewhere has the team of people required even to do a paper full cost analysis of the two approaches, and 'we' certainly don't have the ability to actually test it.

My own thought is that Musk is a smart bloke, and employs a lot of smart people. He's unlikely to have overlooked anything obvious. He could be wrong though. It just seems unlikely.


Offline envy887

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Quote from: fredinno
...
On a serious note, who would do that? I can't see SpaceX spending 500 Million dollars making a rocket, only to then launch 5T satellites. That would cost mare than any F9.
...

BFR with a sat deployment US will have the performance to put 5 to 10 of those 5 tonne sats in GTO per launch. At current F9 prices that's $300m to $600m in revenue per launch. And then do it again 5 to 10 times with minimal refurb cost. As long as they can sell a lot of cheap seats to GTO they have a decent reason to build BFR.

GTO doesn't require putting sats in different orbits since they get to their orbital slots by timing perigee raise. Reuseable SSTOs can't do GTO launches, they can barely get to LEO.

Offline Pipcard

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Quite. Since there is currently no evidence one way or the other, until we have reusable FH's and a reusable design like the Angara to compare, the argument is going nowhere.
And only if that reusable Angara uses boostback similarly to Falcon 9 instead of wings and jet engines.

Quote from: fredinno
...
On a serious note, who would do that? I can't see SpaceX spending 500 Million dollars making a rocket, only to then launch 5T satellites. That would cost mare than any F9.
...

BFR with a sat deployment US will have the performance to put 5 to 10 of those 5 tonne sats in GTO per launch. At current F9 prices that's $300m to $600m in revenue per launch. And then do it again 5 to 10 times with minimal refurb cost. As long as they can sell a lot of cheap seats to GTO they have a decent reason to build BFR.

GTO doesn't require putting sats in different orbits since they get to their orbital slots by timing perigee raise. Reuseable SSTOs can't do GTO launches, they can barely get to LEO.
Who knows what refurb cost they will have, it's going to involve a reusable second stage that's on the scale of the Shuttle Orbiter or even larger. He's also one of those people who has doubts with the savings you'd get from reusability because it goes against "mass production" (he said 40% savings was "optimistic"), and so he wants the reusable 5-core so that it can also take advantage of mass production. And if you haven't noticed, he's talking about problems with launching to different low Earth orbital slots, not concern with geostationary transfer orbits.
« Last Edit: 06/13/2016 05:38 PM by Pipcard »

Offline envy887

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Who knows what refurb cost they will have, it's going to involve a reusable second stage that's on the scale of the Shuttle Orbiter or even larger.
The Shuttle orbiter saved 60 or 70% by refurbishing rather than building a new one, despite basically throwing away 3/4 of the launch stack. The problem was that the new one cost a couple billion dollars. SpaceX's costs are far lower than NASA's up front, so even with high refurb costs they won't be nearly as expensive as the shuttle for much greater performance.

Quote
problems with launching to different low Earth orbital slots, not concern with geostationary transfer orbits.
What problems? There are lots of LEO orbits, but very few that are worth $$$ to launch to. Almost all of Falcon's manifest goes to 3 orbital inclinations: GTO, ISS, and polar/SSO. Launch to the right inclination, and use the extra performance to deploy directly or to a transfer orbit.

Offline Space Ghost 1962

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Answered the OP accurately. The response was evasions and not genuine. This is not a paper rocket (or KSP) forum, so the mods should delete inappropriate posts. My support of the OP was in regards to actual, factual issues.

In answer to the larger question that spans derivative posts to this, of using a smaller LV (say sized to fit) rather than a reused, larger LV -  no smaller LV can economically support a new business in the shadow of such, outside narrow special cases (like the possibly mythic operational space need).

Here's why - once a larger vehicle succeeds economically, that caps the development costs plus fixed base costs, while redirecting the economics in the direction of "max flux" of launch frequency. The net effect is to undercut new rivals.

Cutting to the conclusion - assume F9/FH is a successful stepping stone to BFR/BFS. Once operational, aggregating launches onto a handful of LEO launches to lift a few 100T of payloads would more than satisfy all foreseeable need of global market (assumes secondary transfer to appropriate orbital planes/polar/lunar/C3/..., which would not be insignificant but "distributed launch" or other could easily handle) as a means to underwrite operation through "generic launch services".

This is sort of what Jim is alluding to with his Demolition Man "Taco Bell of launch service providers".

So that's why operating an F1 when you have F9 is not going to happen. And the paper rocket discussion should end now.

Offline Pipcard

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My intention was not to evade your arguments, I was merely trying to act as a devil's advocate/proxy (until he arrived) and point out the ways that fredinno has and might have responded. I only wanted a consensus to be reached on the issue of a 5-core reusable launch vehicle vs a 3-core maximum or a monolithic launcher.

(also, any speculation about BFR on this forum is, as of now, speculation based on statements by Musk about a paper rocket)
« Last Edit: 06/14/2016 03:51 AM by Pipcard »

Offline baldusi

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BTW, there is a very fixed cost per stage. You have to check connections, interfaces, mate, integrate, etc. Each needs to be certified and thus need every process and part manufacturing and acceptance history.
Practice shows that the trend is to less stages, not more. Specially for comercially competitive launches. Even Soyuz-5 project is done to reduce parts!
Another excellent example is EELV, Delta IV went with lots of similar stages so they could get everything from the same line. Atlas V has a single core. Guess who cost half as much?
So anyone can dismiss without any actual experience and state such falsehood as "sea ships are cheap".

Offline Pipcard

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BTW, there is a very fixed cost per stage. You have to check connections, interfaces, mate, integrate, etc. Each needs to be certified and thus need every process and part manufacturing and acceptance history.
Practice shows that the trend is to less stages, not more. Specially for comercially competitive launches. Even Soyuz-5 project is done to reduce parts!
Another excellent example is EELV, Delta IV went with lots of similar stages so they could get everything from the same line. Atlas V has a single core. Guess who cost half as much?
So anyone can dismiss without any actual experience and state such falsehood as "sea ships are cheap".
Indeed, "certification" was especially the word I was looking for when trying to explain the complexity of multi-core configurations.

But Angara-5 was also developed recently despite this trend, and has already launched, so that apparently validates it for someone like fredinno. 'If only that could be made reusable (boostback style),' he thinks.
« Last Edit: 06/14/2016 04:42 AM by Pipcard »

Offline fredinno

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Answered the OP accurately. The response was evasions and not genuine. This is not a paper rocket (or KSP) forum, so the mods should delete inappropriate posts. My support of the OP was in regards to actual, factual issues.

In answer to the larger question that spans derivative posts to this, of using a smaller LV (say sized to fit) rather than a reused, larger LV -  no smaller LV can economically support a new business in the shadow of such, outside narrow special cases (like the possibly mythic operational space need).

Here's why - once a larger vehicle succeeds economically, that caps the development costs plus fixed base costs, while redirecting the economics in the direction of "max flux" of launch frequency. The net effect is to undercut new rivals.
That's the point to a modular rocket system, so that no money is spent on new launchers- you just have one baseline, LV- the 1st stage RP-1 or CH4, and the 2nd H2 (or a lower ISP fuel if you want, that's not the point here)

Also, there is a market for smaller LVs. Prehaps Elon is skeptical, but it IS a growing, but highly competitive market. http://interactive.satellitetoday.com/smallsat-launchers-how-a-tech-revolution-gets-to-orbit/
http://www.thespacereview.com/article/2577/1

Elon having a 1-3T to LEO rocket has a purpose, since satellite operators generally prefer being sent to the orbit they want (esp. in LEO/MEO), as that increases the capability (being in the best possible orbit), reduces the propellant used to get to the needed orbit used by the spacecraft, and saves cost for the launch operator, at least at higher launch rates. It is however, slightly more expensive at lower ones, not taking mass production to account.

https://en.wikipedia.org/wiki/Angara_(rocket_family)#Angara_1.1

Using Angara as a baseline, a SpaceX rocket with a STAR63 and a STAR34 in a 3-stage config could carry 1.5-2T to LEO (those motors are fairly cheap, and SpaceX would not have another factory to maintain, since STAR motors are already needed by NASA anyways.), and using the native second stage, 4T to LEO (which probably doesn't have any major forseeable market, but it would provide a cheap NASA planetary probe option to replace the Delta II. Smaller NASA probes would actually save costs on the launch end of the equation.

Either way, a 2-core config would look royally weird, but WOULD be useful for the BIG LEO and MEO markets, carrying 8.5T to LEO, and fitting the Atlas V 401 market. It would also be great for all those Dragon (both variant) missions, not to mention all the DOD contracts SpaceX will get.

A 3-core config carries 14T to LEO, in other words, fitting the general OTL F9 payload capacity.

A 4-core config would carry 19T to LEO, or near Atlas 551 capacity, not exactly an empty market.

5-core configs would carry 24T to LEO. If using an H2 upper stage and a large enough fairing, you could theoretically compete directly with ArianeSpace's Ariane 5.

Keep in mind, all payload capacities assume slow-speed barge landing reuse.

Thus, no config (aside from the 2nd config) lacks a market. The ones that would likely launch the most/ be bigger money-making variants are the 5-core/4-core (depending on dual launch or no dual launch capability), 3-core, 2-core, and 1-core (and STAR 2nd stage) variants.

[/quote]
Cutting to the conclusion - assume F9/FH is a successful stepping stone to BFR/BFS. Once operational, aggregating launches onto a handful of LEO launches to lift a few 100T of payloads would more than satisfy all foreseeable need of global market (assumes secondary transfer to appropriate orbital planes/polar/lunar/C3/..., which would not be insignificant but "distributed launch" or other could easily handle) as a means to underwrite operation through "generic launch services".[/quote]

So, launch a 2T IXV on a SLS-sized rocket? ???


You do realize the maintenance costs would be a nightmare?
Reuse isn't free you know... there's still work left to be done once that booster returns to shore.

[/quote]
This is sort of what Jim is alluding to with his Demolition Man "Taco Bell of launch service providers".

So that's why operating an F1 when you have F9 is not going to happen. And the paper rocket discussion should end now.
[/quote]
But wasn't that the point of the thread, of a hypothetical modular F9 rocket? Why is this thread even still up then?

BTW, there is a very fixed cost per stage. You have to check connections, interfaces, mate, integrate, etc. Each needs to be certified and thus need every process and part manufacturing and acceptance history.
Practice shows that the trend is to less stages, not more. Specially for comercially competitive launches. Even Soyuz-5 project is done to reduce parts!
Another excellent example is EELV, Delta IV went with lots of similar stages so they could get everything from the same line. Atlas V has a single core. Guess who cost half as much?
So anyone can dismiss without any actual experience and state such falsehood as "sea ships are cheap".
Delta IV is more because it has 2 2nd stage tanks diameters, H2 fuel on the 1st stage, a massive H2 engine, and overall made way too high on the end of the "smart" rocket scale. It's not a very good comparison to compare between that and Atlas V.

Not to mention, there are numerous backlogs to that supposed "trend" than Angara- Ariane 6, the rocket slated to come closer to F9 costs than anyone has ever done so far, uses MORE staging events than Ariane 5 (smaller boosters). Atlas V and Vulcan use the same amount of stages per variant- as is the same with H-II to H-III.
Also, F9 to F9H.
I could also say Saturn V to SLS, but that's not too relavant, since that was created to reduce development costs in mind...

It seems every rocket that is going up the staging event number is going modular. Which is what I am advocating.

Offline kch

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So that's why operating an F1 when you have F9 is not going to happen. And the paper rocket discussion should end now.

But wasn't that the point of the thread, of a hypothetical modular F9 rocket? Why is this thread even still up then?

A very good question.  Perhaps one (or more) of the mods could clarify?

Offline Toast

That's the point to a modular rocket system, so that no money is spent on new launchers- you just have one baseline, LV- the 1st stage RP-1 or CH4, and the 2nd H2 (or a lower ISP fuel if you want, that's not the point here)

But you do have money spent on new launchers, because a single-core rocket does not behave the same as a three-core rocket, which does not perform the same as a four-core rocket, etc. There's changes to the structural bodies of the rockets, changes to the flight profiles, concerns about recontact during complex separation events, etc. Look at all the delays and trouble SpaceX has had with the Falcon Heavy, and you're honestly suggesting that they should implement more variants? SpaceX has absolutely dominated the industry in pricing, and they've been doing it in large part by ignoring many common industry tactics, including "dial-a-rocket" approaches. The Falcon 9 has showed how making a single rocket efficiently and well is an extremely potent tactic, and you're suggesting they ditch the very tactic that's made them successful.

Also, there is a market for smaller LVs. Prehaps Elon is skeptical, but it IS a growing, but highly competitive market. http://interactive.satellitetoday.com/smallsat-launchers-how-a-tech-revolution-gets-to-orbit/
http://www.thespacereview.com/article/2577/1

Yes, a significantly less lucrative one. And a market full of "paper rockets" that never make it past development. Falcon 1 made it, and despite having invested in its design and manufacture, SpaceX ditched it, and with good reason. Investing in the Falcon 9 has been a smart long-term move. If the smallsat business was really all that lucrative, SpaceX would have kept the Falcon 1 in production.

Using Angara as a baseline, a SpaceX rocket with a STAR63 and a STAR34 in a 3-stage config could carry 1.5-2T to LEO (those motors are fairly cheap, and SpaceX would not have another factory to maintain, since STAR motors are already needed by NASA anyways.), and using the native second stage, 4T to LEO (which probably doesn't have any major forseeable market, but it would provide a cheap NASA planetary probe option to replace the Delta II. Smaller NASA probes would actually save costs on the launch end of the equation.

Despite what Kerbal may lead you to believe, it is a popular phrase around here that rockets are not Lego elements. This also completely ignores SpaceX's strengths again by suggesting they purchase and use engines manufactured elsewhere, when what has made SpaceX so competitive is their vertical integration in manufacturing. It is highly doubtful that by the end of all the investment in designing a new rocket, purchasing components instead of manufacturing them, testing it and flying it that SpaceX would be able to gain enough margin on flights to make the effort worth it.

Either way, a 2-core config would look royally weird, but WOULD be useful for the BIG LEO and MEO markets, carrying 8.5T to LEO, and fitting the Atlas V 401 market. It would also be great for all those Dragon (both variant) missions, not to mention all the DOD contracts SpaceX will get.

SpaceX is already doing quite well poaching Atlas payloads, and already decided against a smaller Falcon for launching the Dragon. The Falcon 5 did not have enough power to lift the Dragon, which was a large part of why SpaceX scrapped it. If you think you know better, maybe you'd better call Elon and let him know.

A 3-core config carries 14T to LEO, in other words, fitting the general OTL F9 payload capacity.

Yes, with more complicated manufacturing, launch logistics, landing and refurbishment costs, and additional staging events making the rocket more risky. Thanks but no thanks.

A 4-core config would carry 19T to LEO, or near Atlas 551 capacity, not exactly an empty market.

Falcon 9's upcoming thrust upgrade lets it lift more than that to LEO (22.8 tons, if I recall correctly). You've now invented four rockets and counting to do a job SpaceX has done with one.

5-core configs would carry 24T to LEO. If using an H2 upper stage and a large enough fairing, you could theoretically compete directly with ArianeSpace's Ariane 5.

As with the Atlas, SpaceX is already doing quite well poaching Ariane customers. This is a needlessly complicated rocket that would only be more capable than the F9 in extreme fringe cases (22.8t < payload < 24t). The Falcon Heavy will already provide plenty of coverage for larger payloads and is cheaper than the Ariane 5 as well. You're trying to solve problems that don't exist.

Keep in mind, all payload capacities assume slow-speed barge landing reuse.

Thus, no config (aside from the 2nd config) lacks a market. The ones that would likely launch the most/ be bigger money-making variants are the 5-core/4-core (depending on dual launch or no dual launch capability), 3-core, 2-core, and 1-core (and STAR 2nd stage) variants.

Your money making variants are also the most complex, which historically has boded poorly for reliability. Meanwhile, SpaceX can launch the same payloads as virtually every configuration you've dreamed up with the Falcon 9, which they can manufacture extremely efficiently and cheaply.

So, launch a 2T IXV on a SLS-sized rocket? ???

SpaceX does not have to compete for every payload in the world. They had a rocket that was designed for small payloads, they decided it wasn't worth it.


Reuse isn't free you know... there's still work left to be done once that booster returns to shore.

A fact you conveniently ignored when you proposed a rocket with five cores, each of which would need to be refurbished independently as compared to a single Falcon 9.

Delta IV is more because it has 2 2nd stage tanks diameters, H2 fuel on the 1st stage, a massive H2 engine, and overall made way too high on the end of the "smart" rocket scale. It's not a very good comparison to compare between that and Atlas V.

And yet you suggested creating a complex set of various stages and an H2 stage on a Falcon rocket earlier. You've completely ignored all of SpaceX's strong points and made suggestions that all run counter to them.

It seems every rocket that is going up the staging event number is going modular. Which is what I am advocating.

And all of them have utterly failed to come close to SpaceX's launch pricing.

Offline Pipcard

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As with the Atlas, SpaceX is already doing quite well poaching Ariane customers. This is a needlessly complicated rocket that would only be more capable than the F9 in extreme fringe cases (22.8t < payload < 24t). The Falcon Heavy will already provide plenty of coverage for larger payloads and is cheaper than the Ariane 5 as well. You're trying to solve problems that don't exist.
Just a clarification: he was assuming 24t in reusable barge landing mode. His 5-core is supposed to be the near-equivalent of OTL's (our timeline's) 3-core Falcon Heavy.

Offline Toast

As with the Atlas, SpaceX is already doing quite well poaching Ariane customers. This is a needlessly complicated rocket that would only be more capable than the F9 in extreme fringe cases (22.8t < payload < 24t). The Falcon Heavy will already provide plenty of coverage for larger payloads and is cheaper than the Ariane 5 as well. You're trying to solve problems that don't exist.
Just a clarification: he was assuming 24t in reusable barge landing mode. His 5-core is supposed to be the near-equivalent of OTL's (our timeline's) 3-core Falcon Heavy.
The point still stands, though: There's not all that much money out there that SpaceX is missing out on when it comes to marginal cost differences between a Falcon Heavy and a hypothetical five core mini Falcon, especially when the Falcon 9 can lift so much.

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Offline envy887

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Elon having a 1-3T to LEO rocket has a purpose, since satellite operators generally prefer being sent to the orbit they want (esp. in LEO/MEO), as that increases the capability (being in the best possible orbit), reduces the propellant used to get to the needed orbit used by the spacecraft, and saves cost for the launch operator, at least at higher launch rates. It is however, slightly more expensive at lower ones, not taking mass production to account.
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Do you have numbers with sources for payloads that actually need unique orbit capability? In 2015, about 75% (63 of 87 launches) went to only 3 orbits: GEO, sun-synchronous LEO, and ISS LEO. Almost all the commercial revenue goes to those orbits.

Ref: http://www.spacelaunchreport.com/log2015.html

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