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Orbital Sciences Antares rocket explodes after liftoff

nasa.gov

191–200 of 264 posts

Re: Orbital Sciences Antares rocket explodes after liftoff

#191

Wonder if the boat didn't stray into the restricted area yesterday, things would have been different? I know we might never know but I did wonder if the draining and refueling the fuel caused an anomaly somewhere and lead to this? Such a big loss for us.

If so, it's better to discover now. Later on, lives could be lost in a similar situation.

Re: Orbital Sciences Antares rocket explodes after liftoff

#192

Earlier quoted context omitted.

"If you're failing, you're doing something right." I didn't think people said this and meant it. If you succeed, it means you've done the critical things right. If you're failing, it means that you didn't do something right. Or several somethings. Yeah, you can learn from it and do better, and that's great - but that doesn't mean it's a success. It's a failure and - in some cases - a chance to do better the next time…

Success is the ability to go from one failure to another with no loss of enthusiasm. -Winston Churchill Personally I think he meant that eventual success is often achieve by applying this strategy.

It's not just about lost of enthusiasm but also (mostly) about lost of sources (time, money). But what to say? St happens. It's scientifically proved.

http://www.iyqk.com/v/very-expensive-fireworks-compilation-o...

Re: Orbital Sciences Antares rocket explodes after liftoff

#193

More discussion on spacex reddit: http://www.reddit.com/r/spacex/comments/2km5vq/ot_orbitals_a...

Reddit thread is interesting. Pulled this off there... wow https://www.youtube.com/watch?v=Zl12dXYcUTo

If I remember correctly, the cause of this accident was that one of the nozzles had been wired in reverse, causing it to move differently from what the rocket ordered it to.

Re: Orbital Sciences Antares rocket explodes after liftoff

#196
To decide is this is a success or a failure one need to determine exactly where was the error. If this new knowledge contributes to the design of better systems then this is a success, if the actual error provides us with nothing to learn then this is a very big failure. So there is an amortized cost of success/failure in long term enterprises.

Re: Orbital Sciences Antares rocket explodes after liftoff

#197

Using 50 year old Russian engines was a risky move on Orbital's part, but in fairness the NK-33's are a pretty amazing piece of technology. The US has still yet to build anything matching its performance: http://en.wikipedia.org/wiki/NK-33 297 seconds of Isp is huge. The Saturn V's F1 engine only had 263 seconds. And the closest we've come since to that level of performance in a Lox/RP-1 engine is the Merlin 1D which…

"The US has still yet to build anything matching its performance" The Space Shuttle Main Engines had an Isp of 452s and 500,000 lb of thrust, easily the most efficient rocket engines ever built.

shuttle used hydrolox, antares uses kerolox, hardly comparable.

hydrolox engines have vastly superior Isp but come with their own set of limitations.

Re: Orbital Sciences Antares rocket explodes after liftoff

#198

Earlier quoted context omitted.

What exactly was he wrong about?

Well, if you can take 80% as a success rate at a quarter the cost per launch due to re-using old parts, and build that into your business model somehow (insurance, assurance, whatever and however it might be done), then maybe it can be viable as opposed to using new materials and expensive innovation to get a more reliable result at a higher cost. I'm not arguing for that business strategy; I think it would not be su…

It's not only a cost issue - those old engines have performance characteristics that (in some areas) outperform anything that they could buy today off-shelf (as much as "off-shelf" exists for rocket engines), and developing a completely new model would likely be even less reliable than the current situation.
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