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20 minutes ago, RCgothic said:

What are Soyuz's exact numbers? I've struggled to find them in my own searches.

I just googled 'soyuz success rate' and it was there without clicking any additional links. Works for most of the rockets, it seems.

Edit: I just did that for F9 and it shows it's slightly more than Soyuz. Eh, who cares? Team humanity!

Edited by Wjolcz
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10 minutes ago, Wjolcz said:

I just googled 'soyuz success rate' and it was there without clicking any additional links. Works for most of the rockets, it seems.

Edit: I just did that for F9 and it shows it's slightly more than Soyuz. Eh, who cares? Team humanity!

You can go here but it might take you a while. Also hard to know where you do the cut-off.

If you use a contemporary time period with SpaceX then it's easier. The various Soyuz versions (all R-7 derivatives) have had 157 launches since June 4, 2010, six of which failed. The Bayesian success rate over this period is 95.6%. 

If you use the same time period during which Block 5 has been flying, then you have 25 launches and one failure, which gives you a success rate of 92.6%. Not really fair to Soyuz but them's the numbers.

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2 hours ago, sevenperforce said:

If you use the same time period during which Block 5 has been flying, then you have 25 launches and one failure, which gives you a success rate of 92.6%. Not really fair to Soyuz but them's the numbers.

Maybe it’s better to compare failure rates of both rockets since the day Block 5 started flying?

Disregard that, I can’t read, apparently...

Edited by sh1pman
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25 minutes ago, Nothalogh said:

It seems unfair, and that's an understatement, to judge the R-7 from only 2010 onwards

That certainly seems true, but when it comes to reliability, you have to look at who's been building the machines lately. There should have been significant staff turnover between thirty years ago and now. Maybe I wasn't paying as much attention over the last thirty years, but my impression is that the Russian space program has had more anomalies than usual in recent years.

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I just watched the Starlink swarm pass overhead at 5:28 PM. The prediction listed at Heavens-Above website was accurate, with the swarm passing close to Vega. I counted 50 of them...but they were going in and out of view, so I could have easily missed some. There was one object that was brighter than the others, but was dimmer than Vega. The sky was still pretty light, so these were not particularly easy to see (I could see them well overhead at 75° altitude, but they were harder to see as the moved away from overhead).

Hmmm...maybe the swarm was spread out as much as 60 degrees...but I couldn't measure that well, since I couldn't see them all at once.

Edited by Brotoro
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12 minutes ago, StrandedonEarth said:

my impression is that the Russian space program has had more anomalies than usual in recent years.

No doubt, but it still stands that the R-7 is one of the most impressive launchers of the entire history of spaceflight

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38 minutes ago, StrandedonEarth said:

Russian space program has had more anomalies than usual in recent years.

I read somewhere that for Roscosmos this October marked one whole year without anomalies for the first time since early 2000-s.

Huge win!

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1 hour ago, sh1pman said:

I read somewhere that for Roscosmos this October marked one whole year without anomalies for the first time since early 2000-s.

Huge win!

Well, it helps a bit that they've been launching less over the last few years... :P

 

(Not that much, though. Hopefully this means that they are cracking down on quality control problems, but... their budget only allows for so much)

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IIRC they never had to do the in-flight abort test to man-rate it, right? It's kind of surprising they didn't drop it at this point. Seems like a lot of work with not much in return. I know it's data but since NASA doesn't require it then they probably trust SpaceX enough.

Edited by Wjolcz
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3 minutes ago, Wjolcz said:

IIRC they never had to do the in-flight abort test to man-rate it, right? It's kind of surprising they didn't drop it at this point. Seems like a lot of work with not much in return. I know it's data but since NASA doesn't require it then they probably trust SpaceX enough.

Because it's a way to flex on the competition

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2 minutes ago, Nothalogh said:

Because it's a way to flex on the competition

I'll just chalk it up to being... thorough... <_<

SpaceX can also do it a lot more economically than... those other guys. Used booster, probably a surplus/STA tank, dummy engine, and potential capsule re-use. The test itself probably won't cost them that much, relatively speaking, while ULA would have to spend nearly as much as an actual launch.

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8 minutes ago, Wjolcz said:

IIRC they never had to do the in-flight abort test to man-rate it, right? It's kind of surprising they didn't drop it at this point. Seems like a lot of work with not much in return. I know it's data but since NASA doesn't require it then they probably trust SpaceX enough.

There are different ways to establish that the LES will work. Boeing is taking one path, SpaceX is taking another.

The issue with Boeing would be that if they want to do it, they need to get an Atlas to Max Q. That's sort of expensive. For SpaceX? Propellant cost, plus a dummy tank (someone else bought the booster the first time it flew).

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16 minutes ago, Wjolcz said:

It's kind of surprising they didn't drop it at this point.

This is not how these things work.

You submit a plan for how you are going to certify your product. After review and negotiation, the plan is approved. It does not have to be the same plan as anybody else. You have to meet the same rules, but you are allowed to come up with your own way to demonstrate that, as long as your way of doing it is approved.

Then you execute the plan. Once the plan is approved, you don't just start dropping parts of it.

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