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Comment by hughes | Hacker News Reader

As the presenters repeatedly said throughout the livestream, even when the landing fails it is a great source of data to integrate into future landing attempts.

So far it doesn't appear that the landings have failed for the same reason twice. Not learning from past mistakes is really the only failure.

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>As the presenters repeatedly said throughout the livestream, even when the landing fails it is a great source of data to integrate into future landing attempts.

That's sort of half joke and half spin. It's hard to argue having a failure and learning you shouldn't have designed your rocket with a particular flaw is better than not designing your rocket with that flaw in the first place.

Unknown unknowns? As much as you prepare there will always be things that slip between the cracks.

Oddly enough, sometimes letting things fail is the cheapest way to create a better design. Not necessarily in direct costs, but getting a great product out in 30 years is rarely an option.

Has SpaceX actually cleaned out and reused any of their recovered rockets yet? I'm guessing no, they're still analysing them, but it'll be interesting when they do. (Damned if I'd want my payload on the first recycled rocket...)

Elon says first reflight's targeted for Sept/Oct. https://twitter.com/elonmusk/status/740296489532948480

remember to always take Elon's time preditions with caution, he originally said CRS8's booster (the first landing on the ASDS) would be ready for flight in "june, maybe july"

I'm sure they're doing their best, but space takes time.

"space takes time" is pretty good. Understood they could miss the date, but that's what Elon said they're targeting. If the first re-use is October 2017, I'll still be impressed as I'll bet the timeframes compress over time.

A re-used rocket should be more reliable than the first go-around. Purely because if anything is likely to go wrong it will either happen on the first run or after N runs that is enough to wear a component out. N is likely much greater than 1.

That may be true in the long term, but that may not be true for the first few attempts until they understand the sort of things that are stressed/weakened/generally affected by the first launch.

unless some significant wearing happens during descent

That's the hope, but we don't have enough experience to know whether or not it's true. The analogy people like to use is airliners, but airliners don't get anything like the g-forces or heat load you see on a returning rocket stage.

s/flaw/optimisation

Sometimes the only way to improve a design is by accepting the chance if a higher failure rate.

Local maxima!

Of course it is hard to argue that, It is much better learning that you shouldn't have designed your rocket with a particular flaw than the alternative.

The alternative is not designing your rocket with the flaw in the first place, using only known and proven technologies, avoiding risks at all cost like gobertment(NASA, ESA) agencies do.

And this is very costly in the long term, because technology does not improve.

The failure is also the failure

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