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Starship Integrated Flight Test 2 at 7 Am Central Time

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Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#521

Post by cratermoon »

Aeolun wrote: post #506
cratermoon wrote: post #503

Earlier quoted context omitted.

> the stated primary objective was to get through staging without blowing up. So I was more or less correct at the top of the thread when I said, "if the launch works through staging, SpaceX fans would declare it a success", and I consider that a low bar.

I think you might build a rocket that was less prone to blowing up, but it might not be as efficient. You might also not be able to build it with a room full of idealistic youths running on inspiration.

I guess if you're a Longtermist, killing a 100 people on a flight to Mars is nothing if you save the human race.

Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#522

Post by schiffern »

Y-bar wrote: post #21
schiffern wrote: post #11

Earlier quoted context omitted.

> the Nasa link *NASASpaceflight NASASpaceflight.com (and their Youtube channel) has no affiliation with NASA.

All these years I thought it was an official channel. When I first saw their logo it also reminded me of National Science Foundation that just cemented my (now corrected) belief.

No worries, it happens to the best of us. And also me. :)

For years I was completely baffled why the National Science Foundation had to certify the wire shelving in my apartment...

https://www.srs-i.com/blog/all-about-nsf-certifications-shel...

Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#523

Post by michaelmrose »

wheelerof4te wrote: post #484
lern_too_spel wrote: post #477

Earlier quoted context omitted.

Wikipedia has an article just for you. https://en.wikipedia.org/wiki/Third-party_evidence_for_Apoll... The real trick would have been sending the astronauts on a rocket into Earth orbit for over a week without being detected by Soviet radar operators, who would have been more than eager to share the coordinates with the world, and then somehow sending radio signals back to Earth always from the direction of the moon.…

[flagged]

Say I make up a conspiracy theory that wheelerof4te is secretly the alt account of Putin. This theory explodes into the public consciousness. Pretty soon the US and European press is talking about it. Putin goes on the record "Hacker news what?" Server logs show that the user is connecting from a ISP in the UK. Someone bribes your ISP for your physical address. The international press descends. You give a press conference where you admit you are the user in question. People show that the same pseudonym is used on other sites that all trace back to you. 1/3 of the planet now knows your name here and your real name. The evidence is obvious and conclusive.

Then for another 40 odd years people randomly spout off did you hear Putin posts as wheelerof4te on Hacker News.

The reason they don't get a strong refutation with evidence is that merely by opening their mouth metaphorically they have proved they have very little interest in reasonable argument. For the record you being literally Putin, crazy as it is, is actually a more reasonable theory than the moon landing being faked.

On a related note Russia due to its anti western propoganda is one of the few places this isn't a massively fringe theory.

You are unlikely to buy any of this I'm aware but have you ever found yourself arguing with a young earth creationist? It's the same feeling.

Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#524

Post by rpmisms »

lutorm wrote: post #447
jccooper wrote: post #207

Earlier quoted context omitted.

AFTS activation indicates deviation from planned trajectory. It's unusual, being so late in the burn. Could be a guidance issue, but SpaceX should be pretty good at that by now. Could be engine underperformance, but we got nominal callouts and it would have to be pretty bad for AFTS to notice with minutes left, so that seems unlikely. I'd guess engine control (due to damage during staging) is the main suspect. We say…

I dunno, it looks like a nominal shutdown to me. The speed readout shows rapidly decreasing acceleration just as the engine displays go out instead of the telemetry suddenly going stale as you'd expect if it just blew up during the burn. Then , after the acceleration has gone to zero, the telemetry goes stale, so my guess would be on something going wrong during shutdown (ullage collapse when the propellant sloshes f…

Manley's fluid hammer theory from rapid shutdown is compelling. Also would explain the large vapor clouds; plumbing exploded.

Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#525

Post by rpmisms »

bryanlarsen wrote: post #167
idlewords wrote: post #113

Earlier quoted context omitted.

They need to redesign the bottom half of the rocket so it doesn't blow up during staging, and figure out what happened to the top half and fix that.

They don't necessarily have to redesign the booster. The booster completed its primary mission of boosting successfully. It survived long enough that it seems reasonable to say that if they wouldn't have attempted boost back it would successfully coasted to a splash in the ocean. So the SuperHeavy booster can likely be used as is, if they're willing to spend an extra ~$50M per mission on not recover the booster.

Plus you get extra tonnage from not having to save enough fuel for landing.

Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#526

Post by rpmisms »

aw1621107 wrote: post #173
mongol wrote: post #90

What is the benfit of hot staging?

To expand on KennyBlanken's answer: Rockets generally want their fuel to be sitting on the bottom of the tank, where the engines are. That's easy enough when the rocket is sitting on the ground and when the engines are firing, but once the rocket starts coasting/decelerating (e.g., when the engines turn off due to reaching the end of their burn) the fuel may drift away from the fuel intakes, resulting in the engines…

Hot-staging is amazing tech. It's odd how Russia is so good at rocket science. Until Falcon, they had the highest thrust-to-weight engine, Soyuz is insanely reliable at this point, and they generally just punch above their financial weight class.

Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#527

Post by lisper »

sverhagen wrote: post #520
lisper wrote: post #504

Earlier quoted context omitted.

Oh, I know. I used to work at NASA. But I still think it's a delightful euphemism. (And yes, I'm being ironic.)

Is it a humoristic (sarcastic) style form, or just a very neutral, matter of fact, professional assessment? I can't tell, in part, I guess, due to esl.

It's not clear either way. But as a neutral, matter-of-fact, professional assessment it sounds really weird because "disassembly" generally implies an orderly process, and this was not that.

Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#528

Post by wheelerof4te »

michaelmrose wrote: post #523
wheelerof4te wrote: post #484

Earlier quoted context omitted.

[flagged]

Say I make up a conspiracy theory that wheelerof4te is secretly the alt account of Putin. This theory explodes into the public consciousness. Pretty soon the US and European press is talking about it. Putin goes on the record "Hacker news what?" Server logs show that the user is connecting from a ISP in the UK. Someone bribes your ISP for your physical address. The international press descends. You give a press confe…

You are speaking from a position where the Moon landing is a proven, undisputed fact verified by everyone. In order for it to be that, it needs to be done again. Speaking plainly, it needs to be repeated in a reasonable enough timeframe, just like every other experiment done in history, in order for it to become a scientific fact.

Instead of admitting that logical conclusion, you are pulling a strawman on me. Our discussion is over.

Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#529

Post by TMWNN »

pantalaimon wrote: post #376
ceejayoz wrote: post #268

Earlier quoted context omitted.

The real question here is what happens with a crewed second stage that has a problem with its engines/fuel. We’ve yet to see designs for the crewed interior beyond very conceptual stuff. Maybe something like https://en.wikipedia.org/wiki/Escape_crew_capsule for launch abort.

How did Space Shuttle approach this problem?

As ceejayoz said, "Death". The system WillPostForFood mentioned is indeed, as he said, extremely limited.

In the very first missions with only two astronauts, the shuttle had ejection seats. They were removed when more than two people flew at a time, because a) it is not possible to add more, and b) crew ride on two decks, not one.

After the loss of Challenger serious consideration was given to designing some sort of escape capsule for the entire crew, but it was decided that the weight and practicality considerations were not worth it.

The bottom line is that it is impossible to design any practical means of high-speed travel that can cover all eventualities. A century of extensive experience has led to air travel being the safest way to travel on average, but there are still fatalities. Maybe once we have a century of experience with Starship and its descendants we'll be able to say the same about space travel.

Re: Starship Integrated Flight Test 2 at 7 Am Central Time

#530

Post by mathgeek »

queuebert wrote: post #443
midasuni wrote: post #339

Earlier quoted context omitted.

Absolute numbers don’t really mean much. More than 14 people have died since this test flight on American roads. Shuttle death rate was about 1 in 75, which is insanely high.

What are the units on 1 in 75? People? Missions? To compare with other launch methods, you'd need to use the same metric. IIRC, Soyuz is actually more deadly, but it's been some time since I've seen the stats. Both Soyuz and the Space Shuttle are by far the most deadly form of transportation.

You can either use 14/833 crew positions (individuals flew more than once), or 14/355 actual people who ever flew on the shuttle. You could also use 2/135 missions. I suppose an argument could be made for 2/269 as well if you want to count launch and reentry as separate risk events.

Source: https://www.space.com/12376-nasa-space-shuttle-program-facts...

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