I just posted this in comments over at NASA Watch, in response to a foolish comment there:
Space X boosters need to become reliable cargo transports before they can be trusted with manned space craft. And with only a 2 out of 5 success rate, they have a long way to go!
I guess this is the new mantra of the simple-minded commercial space bashers — the implication that Falcon 1 is only 40% reliable because of its “2 out of 5 success rate.”
Here is the real story. The vehicle had a flight test program as part of its development. The purpose of flight test programs is to wring out design issues, and it shouldn’t be surprising to have some failures in that process.
The first flight barely got off the pad. They figured out what was wrong, and did a second flight. That one had some slosh dynamics issues. They figured out how to fix that and had a third flight. It had a separation problem because they hadn’t accounted for the longer thrust tail-off of the upgraded engine. They fixed that with a minor software change, and the two flights since were perfect.
In other words, they had some teething problems, but have solved them, and now have a reasonably (certainly more than 90%, and probably high nineties) reliable vehicle.
Remember this as you see these morons continue to say “2 out of 5.”
Clark Lindsey has further thoughts.