Looking at the three most recent Soyuz variants:

Soyuz-U had 765 successes in 786 flights. (97.3%) Soyuz-FG had 69 successes in 70 flights (98.5%) Soyuz-2 has 160 successes in 166 flights (96.3%)

Falcon 9 has 362 successes in 365 flights. (99.1%). That includes the partial failure of the CRS-1 mission, which successfully delivered CRS-1 to the space station but released secondary payloads into a lower than expected orbit. It does't include the AMOS-6 fire, which would bring Falcon 9 down 98.9%.

Falcon 9 is more reliable than Soyuz.

Interestingly none of those numbers is enough to give a significant difference between failure rates in a chi-squared test with p < 0.05 - not even if you pool all the Soyuz variants. Though they do all hit p < 0.10.

Thanks for running the numbers, which I think prove that it's impossible to say that Soyuz is more reliable than Falcon, even if you count AMOS-1 (which feels like it should be counted) and CRS-1 (which I don't).

> And Soyuz has like 4x-5x number of launches of Falcon 9 so direct comparisons like yours don't work.

You made the comparison first. Are you taking it back then?

Jesus please go back to reddit. I was simply pointing out that Soyuz has had a LOT MORE launches than Falcon 9, literally over a thousand more, so no one can in good faith that Falcon 9 is more reliable given the numbers and statistics.

But they can claim, in good faith, that Soyuz is? Im afraid thats not how logic works. Either the error bars are too large to take a position, or they aren't. You can't have it both ways.

Fact remains that Soyuz has over a thousand more launches than Falcon 9 with an average success rate of 98% over all its variants. It's the single most reliable launch vehicle mankind has ever made.

A thousand more isn't very much when you consider "Soyuz" (the way you're using it) has been around since the 60s.

Falcon 9 had its first flight in... 2010.

Id personally rather ride Falcon, but to each his own I guess.

Note that your original comment made no acknowledgement of the number of launches by each country. But now when it suites you, it's all important.

What? I was responding to the person saying falcon 9 is the most reliable vehicle we have.

I was merely pointing out that soyuz has like 1500+ launches over Falcon 9 and that there is no comparison.

> pointing out that soyuz has like 1500+ launches over Falcon 9

Not the current variants. If we’re integrating everything called Soyuz we may we well do the same with Long March and every American rocket that uses similar engines.

Falcon is widely considered the most reliable platform you can launch on today.

Widely considred by whom? Elon Musk? Soyuz has like a 98% average success rate over all the variants.

> Widely considred by whom?

Every statistical audit I’ve seen by someone with a background in aerospace engineering.

> Soyuz has like a 98% average success rate over all the variants

Great. You don’t get to fly on “all the variants,” you fly on the most recent. The RD-107A, 108A and Soyuz-2 are not as reliable as Falcon 9.

As I mention in a sibling post, Soyuz might have more launches, but it also has way more launch failures.

Not just more launches, over a THOUSAND more launches. Soyuz has a 98% success rate. Falcon 9 needs to do A LOT more launches before it can be comparable.