Starship is ready for its 2nd test flight | Hacker News Reader

Starship is ready for its 2nd test flight

arstechnica.com

62 pointsalentred23 comments

The timing for the staging is interesting. On the one hand, you want to light the Starship engines (the 2nd stage) while the SuperHeavy (1st stage) is still accelerating the entire stack. This is to keep the propellants at the bottom of their respective tanks to prevent any bubbles going into the engines. The Starship then needs to be under sufficient thrust to accelerate just as the SH cuts its engines so that the two stages can separate safely.

I'm sure it will be exciting. I just hope sufficient SH engines remain running long enough to try the staging event.

Interesting how fast they switched to that.

The "spin the entire stack" was an interesting approach to staging as well. It is theoretically very simple and elegant, by just using the existing RCS thrusters for separating. It wasn't clear to me if this also obviates the need for a propellant settling burn on StarShip. I'd think it wouldn't, but I'm not sure. There is still a thin atmosphere at the staging altitude, so if StarShip is pointed in the right direction after separating, it should be de-accelerating slightly in the direction of travel.

Which would be the reverse of what you want, it would push the propellant away from the engines.

Wouldn't the methane in Starship still be at the bottom of its tank due to the momentum imparted by the Booster regardless of whether it was still attached?

In a vacuum, maybe. But in any atmosphere, removing the thrust means negative acceleration due to drag. Thus the propellant could start to drift up/forward.

I thought for sure pad repairs would have taken longer than they did. I'll have to start getting back in the livestreams and get caught up on developments. I saw that the latest static fire was successful in that all engines ignited.

It's not the two months that was promised, but 6 mo is still astonishing. I keep wondering to myself, where is this money coming from?, but then I remember just how much cash we straight up torch in traditional mil-spec aerospace. Without anything to show for it, natch.

The US launched 90-90% of all objects into Space my # objects AND by mass. Lets see Europe launch their probes right now. Of course, they can't because they don't have a domestic launch vehicle and Russia is not available.

That is where the aerospace money is going.

There’s a vega launch next month

Vega is an infinitesimal blip on the launch industry and will continue to be a blip.

It costs almost as much as a F9 with almost I believe less than a tenth of the performance. It only exists so that Europe can claim they have access to space as long as your payload is tiny

“ they don't have a domestic launch vehicle”

So your claim was wrong

I'm glad to hear that your side of the aerospace/defense business is working so efficiently! Good on you.

Unfortunately, currency-adjusted capability/cost in (eh, edit, most) classes of US military aircraft and surface vessels has been dropping like a rock in comparison to peer competitors since 2013, which - rather obviously, by this point in world history - by peer competitor we mean PLAAF/PLAN/PLARF.

Most of the reason for this is the fact our peers are semi-command economies, and can steer "commodified" production into dual-use at the tip of a hat. Also, it's called "command" for a reason; they can get away with horrible shit. But another part of the reason is the one that's a bit more obvious: an unholy matrimony of single supplier syndrome with utterly complete regulatory capture. Oh, and assholes, who love the hell out of getting fifteen vacation homes from nonexistent projects.

It's the second one I can do something about, so it's always on the front of my brain (ノಠ益ಠ)ノ彡┻━┻

If it weren't for sanctions, ESA would still be flying soyuz rockets. I wonder if they're considering buying any hardware from rocketlab.

Caveat: I realize that any Musk related conversations come across as combative and either vilifying him or blindly following him - that's not my intention here. That said, personally I can't stand the man, but I'm a huge fan of SpaceX.

After the last launch attempt, every article said the launchpad repairs would take a year or more, without any explanation, and it seemed like everyone just started repeating it as an "obvious fact".

That never made sense to me given the launch tower was mostly intact. So, asking in good-faith: Why did you think the pad repairs would take longer? Do you have an experience in the space, or is it just that you read the repeated "year or more" estimate and internalized it?

I think most of those estimates were based on installing a flame diverter (not easily possible with the base being so close to the water table) and having the rocket-grade concrete cure over a number of months. The original pad they had did take many months to cure.

Now, they have a stainless steel block (with holes to squirt water up out of) over the replacement concrete. Hopefully that system can cope with the pressure from the rocket exhaust.

Preparations for pad repairs and upgrades were well underway before the first flight - the question was not whether they'd be necessary, but how much and how soon. In particular if I remember correctly manufacturing of the steel plating that now forms the pad started all the way back in January.

I was promised that Elon was lying and it would take forever for Starship to launch again and FAA would throw every single book at SpaceX causing massive delays to the Starship project. I wonder where all those people are now.

I dunno about that but I do remember watching it blow up and thinking, "I sure as shit wouldn't want to be on the crew scheduled to fly on that later this year."

Crew won't be launching on Starship any time soon. IIRC the approach being taken for Nasa's human landing system (still several years away) will have the crew launch on SLS, a Starship launching uncrewed and getting topped up in-orbit by tanker ships. Crew will board in lunar orbit to descend/ascend: nobody will be on the booster-assisted part, and launching from the moon will use different thrusters situated higher-up the ship body to avoid digging a hole.

There are private flights proposed, but AFAIK there's no firm schedule. The approach to certification is similar to Falcon 9: have a long series of successful launches. (Unlike e.g. SLS or the Shuttle, which are crew rated during development).

Edit: Maybe you're thinking of Nasa's SLS rocket, which had a successful launch and is meant to be taking crew on a lunar fly-by soon (probably slipped from this year)? (SLS is orange and white with side boosters; Starship is silver and black with fins)

FAA still have ample time for feet-dragging but fingers crossed.

Says not before middle of Sept. Would love to go. Anyone else trying to time a trip?

In this instance defeat has a single father and victory everyone minus one.

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