Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

SpaceX launches Starship v3 rocket

space.com

Post reply on HN
Print view View original

291–300 of 326 posts

Re: SpaceX launches Starship v3 rocket

#291

Post by tcp_handshaker »

Laremere wrote: post #15

Summary from my watch: - Launch roughly on time, after a scrub yesterday. (Sounds like the scrub was due to ground equipment, most notably the water system.) - Initial ascent was good, but then one engine on the booster went out. - Relight of the booster's engines after stage separation for the boost back burn failed. Engines did light again for a landing burn, but seems to have hit the water harder than expected and…

>> As far as overall progress from previous test flights goes, they're at least treading water while making many large changes.

What a kind take on what is again the continuous trend of: Every flight fails for a different reason. And they still cant make the most basic use case: https://www.instagram.com/p/DWzTFAEAhSe/

Re: SpaceX launches Starship v3 rocket

#292

Post by anonymars »

NetMageSCW wrote: post #284
anonymars wrote: post #265

Earlier quoted context omitted.

It seems premature at best to make any sort of triumphant comparison, when Starship has yet to complete an orbit of the Earth while SLS has carried humans to the moon It's especially ironic to talk about not landing on the moon yet, when it is the landing system--aka Starship!--which is the primary bottleneck for that goal I am in no way trying to make this some SpaceX vs NASA pissing contest, but there seems to be a…

They could have made orbit at any time on any flights that reached space. they have deliberately not done so because that is the safest thing to do when developing.

I don't see how that gives them credit. Yes of course they could have burned the engines for a little longer and reached orbit

Were they confident that they could relight the engines and get it back out of orbit? This very test seemed to answer "no"

Re: SpaceX launches Starship v3 rocket

#293

Post by s1artibartfast »

kibwen wrote: post #186
s1artibartfast wrote: post #177

Earlier quoted context omitted.

In short, the more stages the better to discard mass once it isnt necessary, and the larger to the better to improve the ratio of (ship+payload) to fuel. Here is a decent summary. https://gemini.google.com/share/121466b300c1

This is only true to an extent. Yes, a larger rocket means a better mass:payload ratio, but a larger rocket also means more mass in absolute terms, and more mass means more fuel, and more fuel means more mass, and more mass means more fuel, and more fuel means more mass, and so on. This is "the tyranny of the rocket equation", and it places an upper bound on the size of rockets that need to carry their own fuel for a…

You fundamentally misunderstand the implications of the rocket equation. It does not put and upper limit on rocket size for a given gravity. Smaller rockets would not be successful where larger fail.

Due to strucrually efficiency, larger ones suceede where smaller fail due to higher m0/mf ratio

Re: SpaceX launches Starship v3 rocket

#294

Post by adgjlsfhk1 »

s1artibartfast wrote: post #143
adgjlsfhk1 wrote: post #131

Earlier quoted context omitted.

The part that makes no sense to me is why they are going starship scale rather than falcon 9 scale. Had they done their prototyping on a rocket with 9 engines on the first stage and 1 on the second, they could have gotten to raptor 3 (and a falcon 9 replacement) while blowing up way fewer engines, launch complexes, etc. There's a reason Spacex started with the falcon 1 rather than the falcon 9. It's a lot cheaper to…

Time costs money as well. Im guessing the cost is irrelevant compared to a faster timeliness.

part of my argument is that if your test platform is 1/4th the size, you get much faster iterations. the path they took meant that every test destroys 39 engines, a huge amount of rocket fuel, and all of their construction. A falcon 9 design (9+1) with raptor engines would let them already have a falcon heavy capacity vehicle because everything about a smaller scale vehicle is way easier

Re: SpaceX launches Starship v3 rocket

#295

Post by s1artibartfast »

adgjlsfhk1 wrote: post #294
s1artibartfast wrote: post #143

Earlier quoted context omitted.

Time costs money as well. Im guessing the cost is irrelevant compared to a faster timeliness.

part of my argument is that if your test platform is 1/4th the size, you get much faster iterations. the path they took meant that every test destroys 39 engines, a huge amount of rocket fuel, and all of their construction. A falcon 9 design (9+1) with raptor engines would let them already have a falcon heavy capacity vehicle because everything about a smaller scale vehicle is way easier

They already have a falcon heavy capacity vehicle - Falcon heavy. I guess I am confused about what you think they would get out of testing with a smaller platform. It seems like most of their focus is specifically figuring out how to make a large platform work. What do you think would translate?

Re: SpaceX launches Starship v3 rocket

#297

Post by tana_shahh »

Laremere wrote: post #15

Summary from my watch: - Launch roughly on time, after a scrub yesterday. (Sounds like the scrub was due to ground equipment, most notably the water system.) - Initial ascent was good, but then one engine on the booster went out. - Relight of the booster's engines after stage separation for the boost back burn failed. Engines did light again for a landing burn, but seems to have hit the water harder than expected and…

Thanks for the summary It was a good read and you nailed it!

Re: SpaceX launches Starship v3 rocket

#298

Post by ericcumbee »

erkt wrote: post #253
Laremere wrote: post #15

Summary from my watch: - Launch roughly on time, after a scrub yesterday. (Sounds like the scrub was due to ground equipment, most notably the water system.) - Initial ascent was good, but then one engine on the booster went out. - Relight of the booster's engines after stage separation for the boost back burn failed. Engines did light again for a landing burn, but seems to have hit the water harder than expected and…

It was also noticeably wayyy faster off the launch mount. These V3 raptors are pretty fierce. It took off so fast it seems destined to be stretched imminently.

V2 they were bring them up in groups. V3 they start them all up at once.

Re: SpaceX launches Starship v3 rocket

#299

Post by ericcumbee »

stephc_int13 wrote: post #37
Laremere wrote: post #15

Summary from my watch: - Launch roughly on time, after a scrub yesterday. (Sounds like the scrub was due to ground equipment, most notably the water system.) - Initial ascent was good, but then one engine on the booster went out. - Relight of the booster's engines after stage separation for the boost back burn failed. Engines did light again for a landing burn, but seems to have hit the water harder than expected and…

The takeoff looked almost normal but I noticed a slight drift from vertical, likely because one of the engines was dead or dying. Overall the V3 is supposed to be an upgrade but actual progress is more or less stalling compared V2.

I have a hard time saying that its stalled. For one we don't really have the hard data to quantify the V3s vs V2s actual performance. On their first flight we lost one on the booster and one on the ship. I don't know that the boostback burn problems are related to the engine themselves given that they had multiple failures and a premature cutoff. That feels like thats a problem upstream of the Raptor.

Re: SpaceX launches Starship v3 rocket

#300

Post by Zigurd »

globalnode wrote: post #286
NetMageSCW wrote: post #272

Earlier quoted context omitted.

Human rating is irrelevant to what they want to do, it is only a NASA rating - if NASA wants to ride they will have to come up with a rationale but private astronauts can fly on it.

From day one they said their vision was to replace airlines for international air travel.

This vision is impractical, bordering on ridiculous, but there it is in the S-1.
Post reply on HN