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I really enjoyed the latest Starship test flight.
https://youtube.com/watch?v=lFkqZF-Ss7o&t=6250s
It stood out from the first launch (IFT-1) because that was nearly a total disaster: 3 (out of 33) booster engines failed immediately (then 2 more on the way up), and it practically crawled off the pad, which also failed and flung giant chunks of concrete far enough to hit ocean. If a few more engines had failed sooner we might have seen one of the biggest non-nuclear explosions in history. 4 minutes later (at only 29km up and 2100m/s) we did see a pretty big explosion, when they lost control before stage separation and had to terminate the whole flight, and even the termination didn't work properly, with the termination explosive damage taking half a minute to finish off a vehicle it should have wrecked in seconds.
It stood out from the second launch because it actually got the upper stage and booster into their planned trajectories after separation. In IFT-2, right after separation the booster was supposed to boost back towards a site closer offshore (for a controlled splashdown, practice for future returns to launch site), but LOX filters had some kind of blockage, 6 (out of 11) of the restarted booster engines started rapidly failing, and they had to blow it up instead. The upper stage made it almost to their target trajectory, started dumping excess LOX as planned ... and that interacted with a leak, started an engine bay fire, shut down the engines, and triggered another termination. At least all the explosives worked properly that time.
It stood out from the third launch because it actually brought both stages back to splashdown. In IFT-3 the boostback worked, but then the booster was having trouble with control during the descent and then with propellant for the landing burn, so instead of a controlled "landing" on the ocean they got an explosion half a kilometer up. Then, the "orbital" (actually very slightly suborbital, specifically as a fallback for what happened next) insertion worked ... except that their attitude control thrusters froze up. So they got to do their free fall experiments in space, but when it came time to reenter they were slowly spinning, and entered sideways instead of heat-shield-first.
I'm a die-hard SpaceX fan (for reasons discussed here), so take my opinion with a grain of salt too, but I'm excited about an excellent splashdown this time with the booster, and more importantly IMHO they just passed the hardest test in the whole program: getting the largest reentry vehicle in human history to decelerate from orbital velocity while still intact and (albeit barely, this time!) fully operable.
Hell, in honor of the Starship 29 Flap, let's push that "passed the test" metaphor to work far past the point it should have been expected to give up: SpaceX only passed their Advanced Launch Vehicles test with a low D-minus this time, and also the exam paper is kinda charred from where it accidentally caught fire right as they were finishing it, but that D-minus beats their 40% last time, 20% the time before that, and 5% the time before that, and whereas such failure would make other advanced students drop out, SpaceX seems determined to just keep retaking the damn test until they've got the same "A++ and extra credit and they corrected one of the professor's mistakes" they eventually reached on the Intermediate Launch Vehicles test with Falcon 9. And that's a big deal, because so far they're the only ones yet to even pass the Intermediate Launch Vehicles test. Space Shuttle got a low pass from the Teaching Assistant (NASA) but failed when the professor (physics) checked their work more carefully. Almost everybody else elected to only take Basic Launch Vehicles, on the theory that that was all you needed to earn a living, which was true once but is becoming more obsolete each year. The exceptions were a few poor students long ago who failed to scrape up the tuition, one rich student who is having to repeatedly audit the class until they find enough time to get ready for the preliminary exams, and a couple young students who seem pretty smart but either aren't ready to test quite yet or are still mastering the Basic test.
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They finally succeeded with all their objectives, and it was exciting because heat protection failed on one of the flaps and a quarter of it melted off during re-entry but the upper stage still managed all the maneuvers okay and gently splashed into water.
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It's fairly widely accepted that the most difficult and most experimental parts of what SpaceX is hoping to accomplish are the re-entry and landing of the orbital vehicle, so actually demonstrating the ability to complete those tasks (albeit imperfectly) is a big step forward. Also high up on the difficulty scale is a precision landing of the booster, and while we don't know if it landed with the necessary precision, demonstrating the capability to do the soft landing on the booster is also a big step forward.
ETA: Given this is the second flight to put Starship into a suborbital trajectory with orbital velocity, I would recommend @ArjinFerman get his checkbook ready.
I did notice they're making progress between launches a while ago, so the checkbook has long been ready. I doubt I'm wrong about my broader point about SpaceX collapsing, and the revolutionary impact of reusability being a house of cards.
What would convince you otherwise? You've already rejected lower prices as evidence in favor of a conspiracy theory about price dumping, and rejected the apparent conclusions of NASA and DOD inspectors who get inside access to the books to verify the business health for government awards eligibility.
Time. If this goes on for the coming years, and investors are satisfied with whatever they're getting out of SpaceX, that will prove me wrong about Elon's unsustainability. If they go on to build a moon base, like they're contracted to, that will BTFO everything I said, and I will write a massive self-flagellating apology. If they pull of Mars, I'll go on one of those Catholic pilgrimage hiking trails, and actually self-flagellate, as an act of contrition for ever doubting daddy Elon.
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..uhh, what?
Their record for flying the 1st stage booster is doing so 21 times. How's that not impressive?
I feel like "Impressive" is a motte-and-bailey. Musk regularly makes entire series of predictions and promises, and people give him an amount of praise I'd consider valid, if he actually managed to fulfill said promises. But since he hasn't we retreat to acting like the things he accomplished are what earned him the amount of praise he's getting. I heard, on several occasions that "rapid reusability" means rockets turned around as fast, and as often as airplanes. When I see that, I'll be writing my apology letter to Daddy Musk.
I guess I fundamentally disagree with this view because it's anti-aspirational. The aspirational goal is aircraft-like rapid reuse, and yes, that goal has not been achieved. But the actual accomplishment of slightly-less-rapidly reusable boosters good for at least tens of flights is still way more than anyone else has achieved, worthy of great praise, and should not be diminished! I'd much rather over-praise a company that delivers on 25% of its extremely aspirational goals than one that delivers 90% of unambitious goals.
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how much maintenance was required between those flights, and how much did that maintenance cost?
Musk claims that for them, refurbishment cost is ~10% of mfg cost of a booster. If you have a gigabrain theory how it's actually not cheap and SpaceX is borrowing money to sell launches at an artificially low price, I'd surely love to hear about it.
Note that their mfg cost is also a lot lower than for other companies.
Also it seems launching 1 kg to LEO, which used to cost $25k in the Apollo era is now down to $1200 if done by SpaceX.
If BFR which costs $100 million to build each( I refuse to use 'starship', they can go fuck themselves with that name) ends up equally reusable, cost of launching 150 tons to LEO is going to go down to cca 15 million $. (I assume $5 million covers the fuel cost handily especially in Texas). Musk is more optimistic about BFR reusability due to improvements such as no soot anymore but there's the heat shield on upper stage and all that too so who knows.
Meanwhile, in comparable dollars in 1960s, cost of launching a similar amount of mass was cca 1.2 billion $.
If it works out, one could launch an entire aircraft carrier sized ship, in chunks, for less than it costs to build one today. ($12 billion, launch cost 9 billion$).
Pretty funny - we could actually start building space battleships soon. The nuclear salt-water rocket propulsion that would give them range to Pluto and back one tank fairly fast are doable, and if your exhaust has a speed of 66 km/s there's no risk of it spiraling down into Earth atmo anyway.
Naw, just looking for numbers to sanity-check the claim of reusability. 10% refurbishment sounds like extremely good savings.
I think we're going to need to build some things off-planet before battleships are worth having to defend those things, but I'm definately rooting for Musk on this one.
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"When Chernobyl reached peak x power during its explosion it was about 350 gigawatts for a fraction of a second. This is 700 gigawatts continuously, right, it's a non-stop Chernobyl going on."
Well, maybe? For obvious reasons we'll never get the EPA to approve a ground test, and I'd be a bit leery about LEO too, which leaves us just hoping that Zubrin's paper was solid.
Of course, the 66 km/s exhaust version was his conservative design; the really speculative version upgrades the uranium enrichment level from "20%" to "weapons grade" and bumps up the yield, to get the delta-V to a few percent of the speed of light. YOLO, right?
Either way, while I'm generally a big fan of the SpaceX "get hardware flying so if it breaks you learn more faster" strategy, I think I'd be cool with taking things more slowly before assembling a 200,000 megaton hopefully-not-a-bomb in orbit.
Chernobyl also released radiation from reactions that have taken place in the months before, so it's not really a good approximation of harm that'd be caused by using nuclear saltwater rockets for space launches.
It is, however, in essence similar to Orion launches, and the radiation release there was found to not be particularly bad by the engineers worrying about it. I'm not sure what approaches they used, but if they were using LNTR and got a figure of "may give 1 person cancer" then it's probably not a big deal.
In any case, it's one of those questions that can't be answered without a good simulation.
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In addition to what @NewCharlesInCharge wrote, both stages made a soft landing despite some of the engines failing to ignite.
Also, I'm old enough to be amazed by a livestream from a bloody rocket blasting into space. The part where it punches through the clouds and Earth is suddenly small and receding is just great.
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The reentry of the Starship through Earth's atmosphere was the fun part. Skip to the two hour and thirty minute mark of orthoxerox's linked video.
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It went all the way up and down with a soft splash landing, even though the thermal protection failed to the point that the aerodynamic control services were melting.
The video of the melting flaps is wild.
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