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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

#451

Post by cratermoon »

kbenson wrote: post #437
cratermoon wrote: post #384

Earlier quoted context omitted.

I previously said that if the launch works through staging, SpaceX fans would declare it a success. Personally, that seems like a pretty low bar compared to things like Saturn V and even STS, both of which launched successfully to orbit the first time.

What you count as success depends on what your goal is. It's entirely possibly SpaceX could have thrown extra billions at it and had a higher chance of successful orbit, but that doesn't mean they deemed that the most efficient use of time and money to advance the project. Sometimes it's far less costly in time and effort to start it up and see where it fails rather than look it over another 20 times and wrack your b…

> What you count as success depends on what your goal is

Yes. My point is that the bar seems pretty low for Starship, and it's not clear why. Yes, some of the ways they are doing things are new, but overall, building large multi-stage rockets is 50s tech.

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

#452

Post by mcpackieh »

inhumantsar wrote: post #449
wheelerof4te wrote: post #428

Earlier quoted context omitted.

[flagged]

You must be trolling. Do you have any idea how many completely uneventful flights Falcon 9 vehicles have flown? The most recent version (the FT which had its first flight in 2015) has had precisely zero failures across 254 launches. They have a better safety record than any other launch vehicle in history, including the Saturn V and the Shuttle. The deaths stemming from those programs have held back interest in manne…

Yes, wheelerof4te is trolling. He's a Moon landing denialist, but he likes to beat around the bush a lot (e.g. waste your time) before getting to that. Asking a lot of dumb questions like "if [whatever rocket] is so advanced then why hasn't it been to the Moon?" In his mind the answer to these questions is that we've never been to the Moon in the first place.

I remember him doing this routine in another thread earlier this week:

https://news.ycombinator.com/item?id=38261198

https://news.ycombinator.com/item?id=38260917

Don't waste your time with him.

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

#453

Post by michaelmrose »

oceanplexian wrote: post #423
lovecg wrote: post #408

Earlier quoted context omitted.

That’s easy. Give NASA 4-5% of the federal budget like it had in the 60s and we’ll go back in no time. This stuff is ridiculously expensive. It’s not the “how”, it’s the political “why” that doesn’t have an answer right now.

Elon Musk doesn’t have 4-5% of the federal budget and SpaceX is well on their way to doing it. I agree with the parent, there’s something else going on, either with society, or our government.

The grandparent is actually arguing that the difficulty we are having now is proof that nasa faked the moon landing something not even worth debunking.

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

#454

Post by lutorm »

kortex wrote: post #310

What is the sudden change in the exhaust plume at occurs here [1] at 149km / 17650 kph? I believe that's squarely in the thermosphere, and there aren't any step changes in temperature/pressure at that point that I'm aware of. It would make sense if that were near the mesopause, but that's around 100km. Maybe it's something on SpaceX's side of things, a change in the burn profile? Perhaps it's related to losing the St…

Yeah, this is a good question. It could be from the engines, but nothing should change at that point that I can think of, since it's well before shutdown. It might also start to vent something, intentionally or not.

I hope they tell us.

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

#455

Post by dotnet00 »

sroussey wrote: post #352
krisoft wrote: post #275

Earlier quoted context omitted.

> Imagine explaining to the court that the passengers were blown up by your AI algorithm... Autonomous flight termination systems are not "AI". It uses an on-board GPS and INS to figure out where the rocket is. It applies a pre-defined set of rules to the state vector and if any one of the rules fail it terminates the flight. You can read more about them here: https://www.gps.gov/cgsic/meetings/2019/valencia.pdf

Hopefully no GPS jammers nearby.

A bit hard to GPS jam a rocket on the way up.

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

#456

Post by krisoft »

sroussey wrote: post #352
krisoft wrote: post #275

Earlier quoted context omitted.

> Imagine explaining to the court that the passengers were blown up by your AI algorithm... Autonomous flight termination systems are not "AI". It uses an on-board GPS and INS to figure out where the rocket is. It applies a pre-defined set of rules to the state vector and if any one of the rules fail it terminates the flight. You can read more about them here: https://www.gps.gov/cgsic/meetings/2019/valencia.pdf

Hopefully no GPS jammers nearby.

Yes. I'm sure they apply all the mitigations possible.

Worth mentioning that the previous state of the art solution relied on a radio link too. Not sure if it was an implementation where jamming could led to flight termination, or where jamming could lead to failure to terminate a flight. But jamming, and resistance to it, was a concern even before autonomous flight termination.

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

#457

Post by LanceJones »

refulgentis wrote: post #394
ironyman wrote: post #89

- Starship got just below orbit - Booster destroyed during hot staging - SpaceX reporting that destruct system fired on upper stage towards end of burn all in all a pretty good result: clean launch and separation, good performance on the booster during ascent (no engine mishaps this time)

Interesting re: good result...I've sort of lost track because the program's timeline has been extended several times: what sort of results are they shooting for?

Good one. :-) SLS, anyone?

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

#458

Post by dotnet00 »

cratermoon wrote: post #451
kbenson wrote: post #437

Earlier quoted context omitted.

What you count as success depends on what your goal is. It's entirely possibly SpaceX could have thrown extra billions at it and had a higher chance of successful orbit, but that doesn't mean they deemed that the most efficient use of time and money to advance the project. Sometimes it's far less costly in time and effort to start it up and see where it fails rather than look it over another 20 times and wrack your b…

> What you count as success depends on what your goal is Yes. My point is that the bar seems pretty low for Starship, and it's not clear why. Yes, some of the ways they are doing things are new, but overall, building large multi-stage rockets is 50s tech.

The "50s tech" was not based around easily reusable systems. It was all based on explosive bolts, solid fueled ullage motors etc.

On top of that the fuel was much easier to work with and did not involve needing to be able to handle pressurization and sloshing during flips.

It's 50's tech only in the same way that a Ryzen CPU is 70's tech.

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

#459

Post by ben_bai »

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?

There was a estimated 1/16 failure possibility for the first couple flights. Lots of edge-cases where: If XYZ happens, you die.

But we were in a hurry, so it was just part of the project.

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

#460

Post by wheelerof4te »

michaelmrose wrote: post #450
wheelerof4te wrote: post #416

Earlier quoted context omitted.

[flagged]

Don't post conspiracy theories that aren't even worth debunking here. In the same vein people are tired of debunking noahs ark, the young earth, the flat earth, and intelligent design. It's just tiresome at this juncture. It is a waste of everyone's time and if you insist on doing it you can do it on facebook instead.

[flagged]
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