SpaceX attempts second platform landing
 

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Being able to look into the sky and seeing even a small rocket like this launching is something unimaginable and awesome to those who have never experienced something of this nature.

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The launch is slated for 6:05pm tonight. The first attempt was Sunday but was hung up due to technical issues.


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http://www.clickorlando.com/news/spa...veral/31190314

The last attempt roughly 1 month ago failed as the booster came in at a 45 degree angle.
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Any word on who's buying the first flight on a reused first stage?

I believe they will be keeping it in house and using it to conitnue with their ISS loads.

Tonight's launch scrubbed because of strong winds. :(

Next attempt: Wednesday, 18:03 EST!

I doubt that. For the currently scheduled trips, a new rocket was paid for. Also, the first few returns will obviously go to test flights. At some point, someone has to step up and buy a trip on a used first stage for this whole endeavor to become profitable in the near term.

I'm not sure it's the rocket they are actually paying for or the delivery medium. Either way I'm sure that's what their plan is. The viability would have to be proven before somebody is going to buy a used launch rocket. But once it does, they can increase their output in multiples.

And yeah, last night's launch was scrubbed. Can't wait to check it tonight if it does pull through.

Looks like it's gotten scrubbed again, thanks to rough seas in the Atlantic. The launch itself is still scheduled, but the landing will not be attempted on the pltaform but will instead be a "soft landing" into the ocean.

http://www.space.com/28528-spacex-la...-blackout.html

Sounds like the ocean landing went well!

https://twitter.com/elonmusk/status/565659578915115011

I wonder if they had anything filming? Obviously we won't get a video from cameras on the drone ship, as we did with the previous attempt, but I'd say there's a possibility of video from a tracking aircraft, maybe.

EDIT: Oh, and the satellite launch was successful, too.

One would think that the readership of "space.com" wouldn't need this spelled out so verbosely (and incorrectly...)
In fact, L1 is not gravitationally stable, though there are orbits about it that are mostly stable.

Nice find. The article was written nearly immediately after the presser came out from the launch department. Could've been a flub.

Either way. Here's some of the video!

https://www.youtube.com/watch?v=UDKk...utu.be&t=4m36s

Can't locate any of the soft landing.

Attempt #2: Failure (but not by much!)

Coolest photo ever, captured by the chase plane:

https://pbs.twimg.com/media/CCmA1JoUMAAijtC.jpg:large

There's even a Vine of the landing. Coolest Vine ever!

https://twitter.com/SpaceX/status/588143946800463874

I'm pretty excited about this technology.

Oooo, HD video!

Have they isolated what went wrong?

There was a tweet from Musk blaming a sticky valve ("stiction in the biprop throttle valve, resulting in control system phase lag"), but it was deleted pretty quickly. I think the only 'official' statement is: "excessive lateral velocity".

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BargeCam: http://arstechnica.com/science/2015/...lmost-landing/

Anyone know specifically why hovering is out?

I've seen comments around stating: "zero velocity at zero altitude", but no explicit reasons why. My uneducated guess would be that hovering requires more fuel than they want left in the rocket.

EDIT: Nope, not a fuel problem -- hovering is apparently out because with an almost empty first stage, the thrust/weight ratio of the engine is greater than 1, even with the engine throttled down as much as possible. So the engine can decelerate the stage, but can't hold velocity at 0, meaning the only way to land it is to time it so that the velocity hits 0 at the point of touchdown (hence "zero velocity at zero altitude").

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Musk has confirmed that the issue this time was a sticky valve: https://twitter.com/elonmusk/status/589577558942822400

"Cause of hard rocket landing confirmed as due to slower than expected throttle valve response. Next attempt in 2 months."

I doubt it needs to be that precise. More like zero velocity at altitude below which the landing gear can absorb the impact and leave the rocket upright...

If only relighting the rocket wasn't a hard thing, they could just PWM it.