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Comment by mikkupikku | Hacker News Reader

If SpaceX doesn't get Starship operational soon, they're going to lose their advantage to Blue Origin and probably at least one of the several Chinese rocket companies.

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Even without Starship Falcon Heavy is still competitive with New Glenn, and nobody is anywhere close to competing with Starlink (Amazon is still far behind, as is ASTS). And if Starship works SpaceX will still be in the lead for a long, long time.

IMO the only remaining unanswered question for the Starship program is the reusability of the heat shield. There's no reason to believe any other part of it can't work.

I always had the impression that the propellant transfer was the harder question than the heat shield. They have done a transfer demo from one internal tank to another, but they still need to test from one ship to another ship.

I only casually follow the news from r/spacex, but prop transfer is what I see generate the most discussion. It’s a hard requirement for all deep space missions. Where the heat shield could be refurbished between launches.

The heat shield may be a "we don't know how to do the physics" problem, where propellant transfer is a "complex integration of well understood components" problem. If the heat shield requires per launch refurbishment it cripples the colonization dream.

Propellant transfer isn’t necessary for starlink launches.

Deep space missions yes. But Starlink isn't deep space - and neither is the vast majority of commercial payloads.

Propellant transfer is relevant because it's vital for sending entire Starships to Moon and Mars - which are the exciting Starship missions. This includes Artemis. But commercially? Artemis contract isn't even a large part of SpaceX's revenue.

Propellant transfer, with cryogenic propellants, can be done using cryocoolers. It's not too hard of a problem. Besides, Starship only needs prop transfer for Moon and Mars missions, but the later are fantasy and the former probably isn't going to happen either, and actually just regular LEO launches with a fully reusable rocket is where most of the money is anyway.

The heat shield is a huge problem though. Without the heat shield, there's simply no way SpaceX can use Starship to make money.

Heat shield reuse is a big deal for orbital refueling too, because it requires 12+ launches in a short time frame. If you don't have heat shield reuse then you need 12+ Starships and 12+ refurbishments per mission.

Why do you think transfer of propellant is so difficult? We do propellant transfer all the time in space. The only real different is that the liquid is colder and Starship is just plane bigger.

But we pipe around cold stuff in space internal to space ships already quite often.

What is the fundamental limitation that you worried about?

I would say the head-shield is far harder an an unsolved problem, specially with re-use. Refurbish is not economically viable, specially not after 1 launch. That would be against every design goal of Starship. It has never been demonstrated in a practical fashion.

New Glenn has an edge over Falcon Heavy and possibly over Starship when it comes to payload volume.

China is currently building TWO competing starlink-type systems. Given the trajectory of China in recent years, I no longer say "nobody is anywhere close to competing with..." about pretty much anything.

China's constellations are roughly where Starlink was in early 2020, except that their launch costs remain much higher. Yes, they move fast, but SpaceX is one of the few US companies I'd bet on to compete with them.

Also, I wonder how receptive the world will be to Chinese ISPs given their history of internet censorship at home.

SpaceX is ultimately still an American company operating at American scale vs PRC. Last year spaceX had fleet of 18 F9s doing more than 50% of global launches, 80% including starlink. SpaceX stans fixate over 50% and 80%, but ignore that 18 rocket cores is rookie numbers. 7/145 US space launches in 2024 was Non SpaceX. That means US in aggregate build ~25 rockets (i think less since some SpaceX are older cores). Versus PRC 68, about ~80 tyhis year (missing keep missing goal of 100). So we can already see there's a 4-5x difference in total launch vehicles production. When/if PRC sorts out reusables, they get both cadence x volume, and no telling how far they can extend the gap, if anything like auto, fast enough that they can overtake SpaceX in historic payload within a few years. Assuming payload enough demand, which I doubt... outside space weaponization arms race.

I think the world, well mainly govs, many of whom who are already running Huawei network gear would appreciate PRC willingness to accomodate local filtering (censorship) rules with how world is trending towards cyber soveignty.

That said, I can see SpaceX being elevated to Boeing tier strategic asset to compete, assuming Musk badblood doesn't interfere.

SpaceX is absolutely capable of building 80 rockets, if they needed to. Don't forget that they built 132 F9 second stages last year, plus thousands of satellites and millions of user terminals. But they don't need to build 80 first stages because their first stages are getting reused 30 times. Why would they waste time building first stages they don't need? China needs to build 80 full rockets because theirs explode after each use.

Meanwhile the Starship factory is looking like it will be quite productive once the design is locked down.

Upperstage stage 1/6 weight with simple merlin engine. SpaceX might need to build 80 first stages if PRC reusable ends up building 80 first stages that's also reusable 30 times. Whether SpaceX can actually build and operate 80 first stages (very likely), and their associated second stages (more questionable) or realistically 100, or 200, we don't actually know, but we know basically in any mature industry PRC can outscale US capabilities, sometimes dramatically, i.e. 200-300x in shipbuilding.

The low build rate is a consequence of success not an indicator of failure. Falcon 9 gets 30+ flights per core, you don’t need to build 60+ rockets.

The point is once PRC figures out reusables and operates a 100/200/300 fleet of reusables, is SpaceX which is more or less entire American space industrial base able to match. Or it it going to go the way of EV or any other PRC high capacity industry where US can't.

Is that different from, say, a year ago? The Starship concept seems technically sound, and the doubt is about whether SpaceX can actually get there, given the rather slow (visible) pace of progress.

I really want SpaceX to succeed, but the Starship heat shield situation seems quite fucked. I heard they're even reconsidering active cooling now. Maybe they'll figure something out but I don't consider that a foregone conclusion.

> IMO the only remaining unanswered question for the Starship program is the reusability of the heat shield. There's no reason to believe any other part of it can't work.

Is there a tldr someone put together here ?

> several Chinese rocket companies

As much as I want to fly with Chinese rocket to encourage launcher competition and redundancy, export controls prevent me from doing that.

That's for you, but that won't stop the rest of the world

Perhaps. But history suggests that "soon" will still be 6+ years. Scaling up from the first few successful launches of a(n orbital) rocket, to high-frequency / high-reliability / low cost launches of that rocket, appears to be extremely difficult.

I don’t see how. SpaceX is still very agile and has the most reliable launch platform

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