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Posts posted by Rakaydos

  1. So I'm seeing a disconnect between "Near term there's no WAY starship is reliable enough for crew" and "SpaceX will fly a million times before crew, so it'll be safe."

    Lets focus on the middle term. How much iteration can SpaceX do before december 2026? (in preparation for the 2027 mars launch window) Note that reuse doesnt actually figure into the iteration rate, only the expirimentation rate. They can fly, say, SN37 a total of 50 times, but they cant make any improvements based on those flights until they build SN38.

    So Starbase seems to have a starship production rate of about 1/month. They're actually a bit faster, but building boosters before they qualify landing will slow them down at the beginning, so we'll call 1/month an average.

    SN20 will be finished and stacked  before the end of august 2021. That gives 4 months (and thus 4 starship iterations) in 2021, 12 in 2022, 12 in 2023, 12 in 2024, 12 in 2025, and 12 in 2026.

    That's (approximately, see assumptions earlier) 64 starship iterations before the first crewed mars flight. Not exactly edison's "I have found a thousand ways NOT to make a lightbulb", but it's also not counting computer simulations for the obvous pitfalls, and software changes that do not require a new-build starship. It also doesnt figure in Raptor upgrades- Raptor v2 is in the pipeline, and Elon doesnt expect to be satisfied until at LEAST Raptor v5, and raptors have their own iteration rate, independent from starships.

  2. 9 minutes ago, JoeSchmuckatelli said:

    I really see that as an aspirational goal or just public relations - as in 'we've already done Moon, let's be the first to Mars!!!' 

    I really doubt Mars - if it happens in the next 15-20 years - will be done in-house.  Moon was a contract award (and if Moon works, then Mars should work) - so by snatching the contract he gets to continue to develop on someone else's dime. 

    Let's not forget that 'commercially viable space company' is of necessity a for profit enterprise.  And absent competition from BO / ULA / Boeing / etc... What we will get is Ma Bell.*

    *(something that works but does not innovative) 

    Oh - and @mikegarrisonis correct - putting up SX aspirations and plans as foregone achievements is naive. 

    If it takes 15 years to reach mars, it means that SpaceX as we know it is dead.


    Because they carefully pick their shareholders, SpaceX cannot be thought of as a normal "for profit" company. Noone is expecting a return on their investment before reaching mars. For many, reaching mars IS the return on their investment, and will fight any abandonment of that goal.

  3. The shuttle might have been worthy of comparison, if it had been allowed to iterate. But the reward structure was all wrong.

    NASA proposed a cheap reusable shuttle, but had to compromise the design with extra, dumb requirements from the military to get enough funding. And once they had the prototypes, development funding was cut off. the expence of maintinance was a plus as far as the political class was concerned, and it's main mission was to keep russia employing soviet rocket scientists, building a russian annex to Space Station Freedom so the soviet scientists didnt go to Iran or northKorea to make ICBMs. 

    SpaceX wants to go to mars, on it's own dollar. To do that, they need a mars rocket that can they can afford to fly on their own. A rocket that affordable is ALSO monopoly-formingly good for the existing launch market on earth. Their boss understands that the prototype is not the finished product, and that there's always room for improvement. This is what is pushing Starship development.

  4. 3 minutes ago, Jacke said:

    Maybe SpaceX makes enough over the lifetime of each launch vehicle article to makes some gross profit.  I suspect that's true.  But that's about all we can do until there are a lot more numbers in a lot more detail with a lot more confidence and someone independent with a lot of knowledge of the field weighs in on it.

    So over 10 flights, you will accept that SpaceX saves more money flying the F9 booster again than building a new booster.

    Superheavy, meanwhile is supposed to be cheaper to build, but also good for a thousand flights.


    Note that SpaceX will probably not achieve that with their early models. The early F9rs were considered good if they got 3 flights. But once they learned how it worked, the doubled down and have flown boosters past even ULA's expectation of reuse profitability. The early superheavies wont reach 1000 flights, but spaceX will throw them away until they figure out how to make a superheavy that can.

  5. 2 minutes ago, .50calBMG said:

    Yes, those were all military, and they were all cryo. Anyway, before this gets any more off topic... Starliner no workey again

    As much as I'd like to cheer this for team SpaceX, I have to boo team USA, since we're stuck relying on putin for Starliner's launches until it's online.

  6. 4 hours ago, kerbiloid said:

    If the plane flights were delayed and cancelled as often as rocket launches, people would still travel by hot air balloons.

    At the very least, rail would get a lot more priority.


    More reason to build a more weather-resistant rocket, thou.

  7. 31 minutes ago, MKI said:

    How far can Starship go without the booster anyways? Has anyone ran the numbers on Starship alone for P2P?

    There was an old elon quote suggesting it could do hypersonic skips out to 10,000 km even without a booster. That's dated information at this point, though.

    7 minutes ago, JoeSchmuckatelli said:

    This is a bit esoteric - but IIRC, several months ago there was speculation about SS tiles, and whether they might use a scale pattern as opposed to the hexes they settled on. 

    Recognizing that snakes and fish use scales that make them really efficient in one direction... Would there be any benefit to scales on SS - where in forward orientation they help air/plasma to distribute across the surface, but then during the landing phase could 'fluff out' and help with the deceleration (instead of a smooth cylinder, the scales would also catch the air) 

    Perhaps a naive question - but just curious. 

    The real advantage to scales is that they can be grown from one edge, an important factor for organic life. Being able to affix tiles from the center is something no living creature can match.

  8. 3 minutes ago, JoeSchmuckatelli said:

    What we need is a Trans-pacific solution... And since the 80s pop-sci has envisioned something like Starship P2P (or a Shuttle - type lander). 

    But even with several flights per day - I don't see the costs as anything but... 

    (... I don't want to say the obvious...


    ...First class? The movie wasnt THAT bad...

  9. 53 minutes ago, SunlitZelkova said:


    Does cadence actually impact pricing? I can understand how expending an LV makes prices high but I don't see how speed impacts it- because it doesn't matter how fast you can launch your rocket again if you don't have something to launch in the first place. This is why I think rapid-reuse is more so suited for a big project like a constellation of SPS satellites, but not integral to other Starship ops, namely standard commercial launches.


    Let's say you're renting a storefront, for a thousand dollars per month That means you have to make in profit a thousand dollars every month, just to avoid going into the red at the end of the month. If you sell 10 gizmos a month, each one has to be sold for a hundred dollars more than what you paid to make/get them. But if you sell a thousand gizmos, you only need them to be 1 dollar more than they cost you.

    Same thing for launch pads, rocket factories, range crew, and general staffing. you're paying the same amount every month whether these people are working or standing around. The more missions you can do, the less each can cost while still covering the end of month expenses.

  10. some tweaks to make the suborbital tourist vehical even more hands off (removing the science gear- i'm pretty sure it was the barometer that was throwing me off course), and grinded out another 100 rep.  Sometimes it seems you get more rep for a mission than the stars strictly indicate- anyone know what's up there? up to 98k funds, but the lowest bidder in the astronaut complex is 400k, even at -698 rep. At least I can see yellow on the rep meter now...

  11. 5 minutes ago, tater said:

    Assuming a SS (no fins etc) is a total of ~25 sheets of steel (smaller at the top, so that excess goes towards domes thrust structure, etc—each dome is maybe 1.5 rings of metal, so this is not perfect), then at 4mm thickness, LSS has ~41.7t metal. At 3mm, it's 31.3t, at 2mm it's 20.8t metal. Raptors are like 2t each, unsure if LSS actually needs 6, might do fine with 4 (3 Rvac, with 1 with gimbal in the center—possibly also a Rvac but with gimbal).

    So 8t of engines. That's a ~50t (no crew stuff included) at 4mm thick, 40t at 3mm, 30t at 2mm. LSS could actually be really light.

    Superheavy's avionics were quoted at a significant tonnage, though, and LSS is going to involve several airlocks and docking ports, and the internal structure to make use of the volume between them. I'd add 20+ tons to that estimate.

  12. Also, I have a REALLY nice suborbit hopper. Even without a pilot, I reach ~75 km at burnout and have to turn off my swivel gimbal to avoid overcontrolling on ascent, and on the way down, physics warp and prime the parachutes while red- they'll activate under 2 km, which is plenty as long as you dont undershoot the highlands and come down in the mountians. when I get the balance right it even swings horizontal when fully deployed.

  13. 34 minutes ago, Blaarkies said:

    Did you find a "Test Terrier at launchpad" contract? With those in hand, you can borrow the Terrier engine to easily do the first Mun+Minmus orbits and Solar science. And if funding becomes a problem and you need to make more funds via contracts, you can complete the contract on the launchpad to get the contract slot back.

    Perhaps it's just my penny pinching, but I keep trying to recover more of the spacecraft than just the capsule, and it feels like that doesnt work at this tech level past low suborbit. 

  14. 9 minutes ago, kerbiloid said:

    Exactly it isn't.
    The "whose" and "how much" are insignificant.

    More of that, they have to prove the "why" again and again every financial year.

    No one prooves significance of most of other business fields.

    Actually, that's typical for tourisim, space-based or otherwise. Just look at any place that relies on tourisim this year.

  15. 4 minutes ago, kerbiloid said:

    You talk about the billionaires, not me.

    Except the tiny market of comsats, currently being actively flooded by several LEOsquatters, I don't see any perspectives for space business, it's a purely governmental sphere, and random peaks of business activity  play no role here.

    Especially on the Moon.

    That's a position the US moved away from 2 administrations ago, during the Obama years. Now, goverment agencies (under the executive branch) actively supports space entreprenurship, even as the legaslative branch mandates goverment dollars get spent on endless pork projects to keep 50-year old jobs.

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