Launch News SpaceX Falcon 9 launch with Jason-3, January 17, 2016

MaverickSawyer

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Agreed. SOme sort of stabilized platform would be required.

Now, if SpaceX and Blue Origin team up to foot the bill for a platform suitable for both of their rockets, that could be interesting. It would certainly spur others to make reusable rockets.
 

Thunder Chicken

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Agreed. SOme sort of stabilized platform would be required.

Now, if SpaceX and Blue Origin team up to foot the bill for a platform suitable for both of their rockets, that could be interesting. It would certainly spur others to make reusable rockets.

Still won't make economic sense. Order of magnitude they're trying to get launches that cost hundreds of millions down to tens of millions. Dropping thousands of millions onto infrastructure to enable it technologically kills the idea economically.

Note that SpaceX has been getting sweetheart deals to use NASA and Air Force facilities to support its launches. As NASA's budget is only in the 10,000 millions, I don't see them willing to part with a significant fraction of their budget to buy such a vessel, especially since there hasn't been a successful landing demonstration. Large rigs still move, just much less than smaller ships.

SpaceX is on their own hook for getting this done, they need to show that it works.
 

RisingFury

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Once again, X marks the spot:

CY98UCXUQAE_hmA.jpg:large
 

RisingFury

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Same link as video, posted by Elon Musk:

Falcon lands on droneship, but the lockout collet doesn't latch on one the four legs, causing it to tip over post landing. Root cause may have been ice buildup due to condensation from heavy fog at liftoff.
 

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So, it strikes again :p
hqdefault.jpg
 

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At least looks like they have engines this time. Depending on how severe was fire after crash it is possible some engines are in good enough condition for post landing inspection. Probably not much to gain after they already have intact stage to study, but still may be possible to get some useful data from this crash.
 

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This is precisely why they test... if you never launch on an heavy fog day, how else will you know ice buildup could mechanically interfere with latching of a landing leg?

Think Kerbal. Incremental bug elimination :p
 

Urwumpe

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They HAD that landing made. Shame on the gear failure.

Still, its doubtful that only relying on altitude information by INS-augmented GPS is enough for landing soft on a platform that moves vertically. Works for solid ground, but likely not for ships.

The landing gear will always get some strong beating that way. Maybe it would really not be a bad idea to have the landing barge communicate with the landing rocket about the position and motion of the barge - after all, that is also needed for letting aircraft land on carriers in normal North Atlantic weather.
 

Andy44

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I am a little surprised at how it exploded after it tipped over. Is that just from the left over LOX? Is the kerosene that volatile?
 

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I am a little surprised at how it exploded after it tipped over. Is that just from the left over LOX? Is the kerosene that volatile?


Well, remember that the tanks are pressurized and thus react pretty badly to damage as well.

Kerosene is not volatile at all, actually it is pretty tough to ignite. But when you create a fuel/air mixture by shaking the tanks and letting Kerosene splash out with some lot of kinetic energy, you can ignite it more easily and then it gets nasty - just remember how large the flames during an aircraft crash can be with nearly empty tanks.

(Liquid) Oxygen only makes the reaction much worse, since it not only makes the reaction of the Kerosene more violent, but also creates new ignition sources, since even metal can burn well with enough oxygen around it.

Toppling a pressurized rocket is generally considered a very bad idea. Unpressurized rockets are only slightly less dangerous.
 

ADSWNJ

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I am a little surprised at how it exploded after it tipped over. Is that just from the left over LOX? Is the kerosene that volatile?

Also, it's made of the thinnest metals and alloys to handle force in an up-down direction, rather than to survive a 13-story high fall and impact on its side. At least this was the last F9 v1.1 core, so it would not have flown again, and it's last act was to help fix this next problem on the path to routine rocket recovery in the coming small number of years.
 

Cairan

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Still, its doubtful that only relying on altitude information by INS-augmented GPS is enough for landing soft on a platform that moves vertically. Works for solid ground, but likely not for ships..

The video of yesterday's attempt would seem to prove the contrary. It remained relatively stable up until that leg slowly got loose and the rocket fell like a giant tree.
 

Thunder Chicken

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Damn, they did stick that landing.

It is really horrifying to see how readily these things explode. As soon as it touches the deck *BOOM*.
CRS-6 was much more violent.

They have to do something about those legs. All four legs have to work. They hit me as being the least robust components on the entire rocket and have no backup.
 

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The video of yesterday's attempt would seem to prove the contrary. It remained relatively stable up until that leg slowly got loose and the rocket fell like a giant tree.

There are two problems with that view. First of all, it only is one landing. Maybe the next could be less favorable. Also the video also shows that the landing was still pretty rough. Just imagine the ship moving up during the final cm of landing and adding vertical velocity. Since it shortens the distance for the rocket to slow down, it could result in much higher landing velocity difference than just the speed of the platform.

Next problem, it could be that the legs could have been stable with a smoother landing, when a partial lock of the landing gear would be enough.

Also, "relatively stable" has a relatively different meaning when you are talking about a 46 meter high rocket stage. Even small differences, to small to be seen in a video, can already mean Meganewtons of force on critical connections. The Crawler of the Saturn V and Shuttle did not keep the rocket vertical within a fraction of a degree for aesthetics, it was really necessary to do that (and will remain necessary for the SLS)

If you look how helicopters land on ships, its really hard to imagine that the rocket stage should stay stable on deck with much less effort. Even if you include that the rocket will never operate during 7 meter waves. Helicopters are literally pressed against the deck until secured or in preparation of take-off, with the shock absorbers being compressed much more than possible by loading maximum cargo into it. And helicopters are generally much more favorable regarding their CG and landing gear layout
 
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Cairan

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You know, people really, really should be taking a step back and look at the whole picture. SpaceX is testing their procedures, pushing the envellop, getting kinks out of the system... However you choose to call it, it still is an experimental phase of flight that almost noone dared to touched (except DC-X back 20 years ago).

Heck, many were still calling for a big boom back on December 21st, saying they wouldn't nail it on the ground either.
 

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You know, people really, really should be taking a step back and look at the whole picture. SpaceX is testing their procedures, pushing the envellop, getting kinks out of the system... However you choose to call it, it still is an experimental phase of flight that almost noone dared to touched (except DC-X back 20 years ago).

Heck, many were still calling for a big boom back on December 21st, saying they wouldn't nail it on the ground either.

Sure, absolutely. But then, SpaceX is also no "rocket stage landing research program" of NASA, but a commercial venture (though it received a huge pork barrel via NASA).

Especially the fact THAT it was still a very risky technology with many possible known and unknown problems made the first successful landing that important. Maybe it was just luck. Sure. But they had been working hard to be that lucky. That deserves a whole lot of respect.

But in the end, what matters is not landings, but boring profits. And that is the real challenge that SpaceX still has ahead of them.
 
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