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Airbus to build 'first interplanetary cargo ship'

bbc.com

131–140 of 219 posts

Re: Airbus to build 'first interplanetary cargo ship'

#131

Earlier quoted context omitted.

Boeing has liabilities which a new company doesn't.

Even if we consider the two funding amounts equal for the sake of comparison (which is a real stretch), crewed Dragon has already delivered while the recent Starliner test flight was riddled with defects.

Being as optimistic as I can without being an idiot: it’s abundantly clear that they are still farting around with welding techniques, but in a complex project of this scale, somebody is always running behind schedule, and if it’s something new, then lots of people are (I worked on support software for the 787, and even among our cohort, my division was the only one that was only slightly behind schedule) and sometimes it’s enough for those people to be sort of scaffolding for everyone else.

If Conway’s Law has any flex in it, you bend the mandate of each group to shift some of their responsibilities to teams that are getting better results and eventually something ships. I suspect this is how they get anything done. It might even be their organizing principle, a sort of self organizing system.

The same might be true for SpaceX, I couldn’t say. What we do know is that they just accepted delivery of welding robots, and I don’t know if that was Plan A all along or they’ve given up on training people to consistently make a clean bead that’s 53 ft long.

Re: Airbus to build 'first interplanetary cargo ship'

#132

Earlier quoted context omitted.

Where are you getting the third two to put in for x? Your number would be phrased as "twice squared twice."

English is a strange language. "Twice squared" could be interpreted both as "Twice as hard, squared" or "Twice as hard, squared two times." Think of the sentence, "A man, twice fooled, shall not be fooled again."

If x is the difficulty, the phrase either means “twice the difficulty, squared”: (2x)^2 or 4x^2.

Or “the difficulty squared and squared again”: (x^2)^2 or x^4.

The GP is asking why x == 2 in the second example rather than just “the difficulty”. English interpretation doesn’t explain that.

Re: Airbus to build 'first interplanetary cargo ship'

#133
post #33

It will be interesting to see what the situation will be like when this spaceship is ready. By that time we should have Starship and New Glenn flying regularly. Even New Armstrong could be close to ready by then.

New Glenn is not that different from Falcon 9 regarding reusability as they will have to expend the upper stage and fairings every single launch.

Didn’t they just recover both fairings on the last launch?

I don’t know how you want to work the math, but it is probably best to think of it in a fractional way. Between accidents and wear do they manage better than 4 launches in average? They just managed 6 for one lower stage, with tighter turnaround time. We don’t know how much of that rocket was reused. So we might be talking about expending 20% of a lower stage per launch, and some higher ratio of upper stages.

Re: Airbus to build 'first interplanetary cargo ship'

#134
post #34

Earlier quoted context omitted.

I don't know. But in any case, it's not just the fuel. Have you seen the proposed Moon-Starship? They'd require some quite impressive crane to even get cargo into the ship. Additionally, there's the problem of the landing site. It's considerably more difficult to land a rocket on unprepared, rocky terrain than on a carefully prepared landing pad. Plus a suitable area has to be found first, too. There's simply no guar…

The moon-starship will not require in-situ resource utilization (ISRU), i.e. no creation of fuel and oxidizer at the target. It is supposed to land with enough propellants to make it back.

I only mentioned the Moon-Starship, because illustrations show nicely how far away from the surface the cargo bay is.

I don't suppose the Mars version will be all that different in that regard, but we'll see.

Re: Airbus to build 'first interplanetary cargo ship'

#135

Earlier quoted context omitted.

"not just twice ...; it's twice squared" So "twice"(2) and "twice squared" (x^2^2) = 2^2^2 = 16

Where are you getting the third two to put in for x? Your number would be phrased as "twice squared twice."

Read "not just twice" as "not only twice".

Then you can read "it's twice squared" as (the first use of twice) + ("twice squared")

The 'it' reference can change. The first 'it' is referencing the difficulty. The second 'it' is referencing the first 'twice', creating the option that 'it' is further "twice squared". Not the most elegant interpretation but a possible interpretation.

Learning to avoiding this vague language is why math majors should still take the occasional poetry class.

Re: Airbus to build 'first interplanetary cargo ship'

#136

Earlier quoted context omitted.

Correct, only the crew mission would return, the rest would be several one-way cargo missions

Pretty sure Musk said the crew mission would not return

From Dr. Zubrin's Reddit AMA:

> for Mars Ascent and Earth return, SpaceX should develop a mini Starship, sized to be an upper stage of an F9. This would create a fully reusable medium lift booster, and reduce Mars propellant making requirements by a factor of 5. A Starsip could lift one of these to LEO fully fueled, after which it could fly to Mars, and return. any full sized Starships that land on Mars should stay on Mars. SpaceX will make plenty of Starships, it won't need any back that go to Mars. A Starship on Mars is much more valuable than one on Earth.

https://old.reddit.com/r/spacex/comments/hgy64k/ask_me_anyth...

Re: Airbus to build 'first interplanetary cargo ship'

#137

Earlier quoted context omitted.

I don't think even Musk, master of the dubious marketing promise, has claimed that; the first ones would be one-way jobs AIUI.

I don't think you can call him Musk "master of the dubious marketing promise" anymore now that Tesla is meeting production goals, SpaceX is landing boosters, re-supplying the ISS, and has brought astronauts to the ISS. His promises are far more reliable than most at this point.

I'm pretty sure you can do that more now than ever, after courts in more and more countries are shutting down their "Autopilot" marketing.

Re: Airbus to build 'first interplanetary cargo ship'

#138

Earlier quoted context omitted.

I don't think you can call him Musk "master of the dubious marketing promise" anymore now that Tesla is meeting production goals, SpaceX is landing boosters, re-supplying the ISS, and has brought astronauts to the ISS. His promises are far more reliable than most at this point.

> now that Tesla is meeting production goals Where's the magic cross-country self-driving car that was meant to show up in 2016? And just how 'self driving ready' are those Model 3s? > SpaceX is landing boosters A mere decade or so after promised. I think both of these are examples of dubious marketing promises, though the Tesla one is more egregious (the SpaceX one is merely extremely late). But either way, I wouldn…

I don't think learning a problem is harder than you thought and then still solving it is a detriment. If anything this community should be the ones that understand that the full scope of a problem often becomes apparent once you're 80% into it.

How many startups are "guaranteed to revolutionize the world in 2 years", take 4 years to get a minimum viable product, and are gone in 6?

You solve the problem, you get my credit. Fully self driving cars though I think should have been more obvious that it wasn't going to happen anytime soon.. not just to Musk but to everyone working on it. It'll get there eventually too, but it's still early days.

Re: Airbus to build 'first interplanetary cargo ship'

#139
post #52

The article mentions a "football sized package". Hope there is no confusion between American and European football.

Reading https://www.esa.int/Science_Exploration/Human_and_Robotic_Ex..., they mean “basketball size”. It seems the BBC thinks their readers do not know how large those are.
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