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Comment by pretendscholar | Hacker News Reader

Does he really have a good track record? If I recall correctly the Falcon 9 has a terrible success rate for a modern rocket. Something like 94 percent.

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Falcon 9

51 launches

48 completely successful

49 partially successful

94% success rate (complete success)

96% success rate (partial success)

Ariane 5

97 launches

92 completely successful

95 partially successful

95% success rate (complete success)

98% success rate (partial success)

Atlas V

76 launches

75 completely successful

76 partially successful

99% success rate (complete success)

100% success rate (partial success)

Delta IV (including Heavy)

36 launches

35 completely successful

36 partially successful

97% success rate (complete success)

100% success rate (partial success)

Proton (since 2010 as an arbitrary cutoff)

65 launches

58 completely successful

59 partially successful

89% success rate (complete success)

91% success rate (partial success)

I don’t really think there is any way in which the adjective “terrible” would be an appropriate use of the word here. Also note the low numbers involved here, the different contexts and the plain arbitrariness of such comparisons. One failure more or less can make a world of difference here, despite maybe not being the most reliable indicator.

94% is about the long term ballpark figure for successful orbital launches but it is true that some newer rocket families may have ever so slightly higher reliabilities.

Now divide that failure rate from dollars invested in each project to truly see the differences.

(Adjusted for inflation etc and remove the arbitrary cutoff for Proton.)

Atlas, Ariane and proton have fifty+ years of investment tail behind them and a fifth generation in atlas is probably more than musk has had in spacex in generation terms no?

Does it include the rocket and satellite destroyed while refueling?

What about Soyuz? IIRC, they haven't lost a manned mission since 1971.

>What about Soyuz? IIRC, they haven't lost a manned mission since 1971.

Neither has SpaceX :)

Soyuz is somewhat more complicated since it's an entire family of rockets:

The Soyuz-FG (2001-today, currently does all manned flights) has a 63/63 success record.

The Soyuz-U2 (1982-1995) also has a 72/72 success record.

The Soyuz-U (1973-2017, also manned flight) has a 765/786 (97%) success rate, with no failure in their manned flights.

The Soyuz-2 (2004-today) has a 68/75 (91%) success rate.

Given the rate at which SpaceX has been improving their line-up you can't really do a 1:1 comparison between platforms that are essentially static and what SpaceX has been up to.

And over time their failure rate has been dropping steadily, since 1/1/2017 they've launched about half of all F9s and all have worked perfectly. It's gotten to the point where the press will crow 'failure' if they don't manage to land the first stage on the barge, which is apples-to-oranges with the rest of the industry, who are - rightly - getting seriously worried.

How many years did SpaceX do over that modern rocket? How many years did NASA do to get to said modern rocket? I'd say he's on a pretty good roll.

SpaceX didn't start in a vacuum, or in the 40s.

And don’t forget in 1969 when they landed on the moon, they had to code all the timestamps in negative.

Neither did Ariane 5, Atlas V, Delta IV or Soyuz-FG. Of course SpaceX profits from the state of the art, but not developing the Xth iteration over a proven and battle-tested design with decades of flight-data is a disadvantage for SpaceX.

SpaceX benefits from being able to inspect landed boosters. This comparison is apples-to-oranges.

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