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SpaceX Landing Attempt Video Released
An anonymous reader writes: Last week, SpaceX attempted to land a Falcon 9 rocket on an autonomous ocean platform after successfully launching supplies to the ISS. It didn't work, but Elon Musk said they were close. Now, an amazing video has been recovered from an onboard camera, and it shows just how close it was. You can see the rocket hitting the platform while descending at an angle, then breaking up. Musk said a few days ago that not only do they know what the problem was, but they've already solved it. The rocket's guiding fins require hydraulic fluid to operate. They had enough fluid to operate for 4 minutes, but ran out just prior to landing. Their next launch already carries 50% more hydraulic fluid, so it shouldn't be an issue next time.
It suddenly occurred to me that I've never heard of a hydraulic system "using up" its fluid before. Anyone know anything about how/why the rocket is different?
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Seems to me that I would save that for emergencies. Use the high speed descent to pressurize air for controlling.
Just saying...
Looks like most of my Kerbal Space Program landings.
How can I believe you when you tell me what I don't want to hear?
I think I've watched the loop 50 times.
This was the first time SpaceX had flown the new grid fin control system on a real first stage under real conditions. They did not know exactly how well the grid fins would behave. As it turned out, the grid fins had to move more than they expected during the descent (or the forces were larger than they expected), so they ran out of hydraulic fluid 30 seconds before landing. This is similar to an airplane losing control of its elevator just before landing. The fact that the rocket reached the barge and that its vertical speed was reasonably slow (certainly not 100m/s) indicates the resiliency of their systems. They are putting 50% more fluid into the system, so this shouldn't happen next time.
I think this video is epically cool. I can watch it again and again. Simply awesome.
This and no other is the root from which a tyrant springs; when first he appears as a protector - Plato (423 to 327 BC)
Now with more fluids! First 3000 customers get an extra half liter!
You know, there are places where being 'innovative' is not the wisest move.
“He’s not deformed, he’s just drunk!”
What gets me most about this is the nonchalant attitude.
"yea we blew up the rocket and the barge, but no biggie. We'll do better next time"
I think that is why nerds get so exited over SpaceX. That attitude of not letting fear of failure dictate future actions.
"There are lies, there are damn lies, and there are statistics"
WTF is going on with the left margin. God damn it, it is broken in every single browser. Are they crapping on classic slashdot to punish us for beta not working?
My guess is that fluids encountering massive temperature and pressure shifts can't be reclaimed in the normal way during the flight? Just a guess though.
he tweeted
Next rocket landing on drone ship in 2 to 3 weeks w way more hydraulic fluid. At least it shd explode for a diff reason.
I am Slashdot. Are you Slashdot as well?
To borrow from the KSP forum, that's "Rapid Unscheduled Disassembly". Or, "explosions", to the uninitiated.
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
Hydraulic systems are in a loop, with the "spent" fluid recirculating back to the reservoir. How did they "run out"?
Where did the fluid go?
The system is an open hydraulic system. Closed systems require tanks and pumps which carry a mass penalty. They only need the system to function for about 4 minutes. Why bother with a closed system when the functioning period is so short. They will increase the amount of fluid by 50% so this shouldn't happen again. All in all a nearly successful experiment.
This and no other is the root from which a tyrant springs; when first he appears as a protector - Plato (423 to 327 BC)
Explain your alternative ideology, please.
What about corporations as large/powerful as states? Are they good or bad?
--
Remember, when feeding trolls, be sure to keep your hand flat.
This was the first Falcon 9v1.1 flight [1] with gridfins and [2] sent to land on a teeny tiny little platform at sea (a MUCH smaller target than an aircraft carrier, while descending from MUCH higher than any carrier pilot and having no wings and only VERY limited fuel and throttle-range for lift and control)
It was an excellent display of competence that puts Boeing and Lockheed-Martin to shame; both mega-corps have been sucking billions from the government nipple for many decades without ever once even TRYING to make such an improvement for which they certainly had the expertise and resources. These giant aerospace companies were born as innovative entrepreneurial entities that invested in technological advances and experiments to advance "the state of the art" in order to win their share of the free market.... but after the deaths of their founders they got hired-gun CEOs and moved to a model of only innovating when they could get the government to give them billions of dollars to do it. With many decades of "cost-plus" contracts (where the government pays "whatever it costs, PLUS some percent as profit") the big bloated defense contractors have had no incentive to innovate (ABSOLUTELY ZERO incentive to reduce costs) and have become lazy. SpaceX and more more like it are needed to drive the big old firms into either returning to efficiency and innovation, or bankruptcy.
doesnt make it any less awesome. I hate vine but hey, in this case its better than no video
have you seen my sig? there are many others like it but none that are the same
Convince stores in the middle of the Atlantic Ocean? At night? In foggy weather? I'm sue we will see other camera views but this isn't capturing pics of some twerp stealing potato chips.
Further, I don't recall Musk saying anything along the lines that this was about you.
Faster! Faster! Faster would be better!
So they only blew up the rocket.
Hey, their competitors would have just thrown it away anyway...
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
It has landing legs. When it hits at a 45 degree angle (that's a lot more than "slightly wrong"), the legs on that side break and the engine assembly smashes into the landing pad.
Some low or mid end high speed cameras would be great. With DC lighting during landing. We could see lots of details. I mean, they could.
The "garbled footage" was a radio signal from the incoming first stage. Getting good communications from a vehicle during re-entry is a hard problem. And a GoPro (at least before this landing attempt) wouldn't have helped much because it would have been on the ocean floor along with the rest of the rocket.
And in the case of this particular landing attempt, it was before sunrise in heavy fog.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
It seems SpaceX is relying on a trial-and-error strategy during the development of the soft landing capability of their booster much more than they (or others in the industry) do for other components or capabilities of space launch or other aeronautical systems. I don't see (unmanned) rockets or drones being developed in this fashion. Even large rockets that can achieve orbit will normally be modeled, simulated and tested component-wise to the point that they will usually work at the first or second attempt when the entire system is integrated and tested for the first time. So why is this so different here? Is it just cheaper? Or is it actually that much harder to make the rocket land softly on its own exhaust jet than to make it go into orbit?
Hey, as these things go, this was a very very good failure. Consider that we've just progressed from the old reality's typical "the vehicle will splash down somewhere in this 500-square-mile area of the ocean," to Spacex's new reality of "we accurately flew down to a 0.0018-square-mile platform, and borked the touchdown on this first try."
I'll take that kind of progress any day.
I think not...(*poof*)
Seeing this and pondering about this problem, I suddenly came up with a terrific idea, for which I'll file a patent as soon as possible.
The basic idea, without revealing too much detail, would be to store some sort of very large sheet of tissue, or some other strong fabric, inside a pack or something. The sheet -- which could be duplicated as needed, to improve safety, let's say three of them -- would be neatly folded in order: 1/ to be stored efficiently and 2/ to deploy quickly and as widely as possible.
At some point in the reentry, let's say a few miles above the landing spot, the sheets would deploy thanks to a system of sorts -- let's say an altimeter -- and, by the magic of fluid mechanics and the Archimedes principle, would slow the rocket enough for it to land safely.
Now that I think of it, that system could be extended to people, who could jump from an airplane, just for fun or for military operations. Hmmm...
The first reports I read said the rocket came down to hard and damaged the platform. I thought it landed vertically by coming in too fast and smashing the platform surface. Watching the video, the rocket landed sideways before exploding. Things always goes badly when they go sideways.
I personally find this is about as cool as anything I have seen in the last decade. What they are doing requires the very best engineering that mankind currently offers -- I'll take this over building 2000 feet tall buildings, or 50 mile long bridges any day.
your idealogy is FALSE and that you blindly and sheepishly support a failed system
All ideologies are false. That's what makes them so tasty. We crave simple rules and easy answers for this complex, interwoven world of ours. And once we subscribe to a set of Answers, we can confidently stride them out upon others... especially those weaker souls who may want to look at an issue from multiple angles and acknowledge the inherent difficulties of society's seemingly numerous and intractable problems. There's nothing better than feeling intellectually invulnerable and knowing that all voices that run in any way counter to your own are automatically corrupt or incompetent, dismissible out of hand without even having to listen to them. The world is so clear when righteousness runs thru your veins.
Whatever the source--left or right, extremist or complacent-- unchecked ideology is the true enemy of humanity .
(Yah, I know... don't feed the trolls, but I've been where AC is, and it is a trap unto itself.)
-1, Too Many Layers Of Abstraction
Remind me again, why doing this crazy rocket landing is better than using a parachute recovery like the shuttle boosters did?
Or hide in your anonymity and know you are a coward
Quite the bluster from an Anonymous Coward.
THE SOFTWARE, IT NO WORKY!!!
Closed systems require tanks and pumps which carry a mass penalty.
Strictly speaking, you don't need multiple reservoirs for a closed hydraulic system. You only need one, and that reservoir can be your accumulator. In practice we usually have at least two; one is the accumulator, and one of them permits degassing the fluid which can be necessary as it heats up. With an open system you definitely only need the accumulator, and some kind of control valve. On a spacecraft, hopefully you also have a backup. A shuttle valve is one valve that lets you pump fluid in (or from) multiple directions, usually two of them, and which you can run with a servo (or however) to get variable control over hydraulic flow. Most hydraulic systems with a pump also need a pressure relief valve, which is a common point of failure. Sometimes they just have a pressure switch, which is another common point of failure.
On a car, the power steering system has a reservoir with degassing typically attached to the pump, but sometimes nearby. The shock absorbers are a closed system, but [typically] use a nitrogen-charged diaphragm to handle the fact that the interior volume of the shock changes; both as the shaft enters the body of the shock, and as the working fluid heats up.
Anyone out there know the specific layout of the control system for each vane? I'd imagine that the fluid is going to the cylinders and then to the control systems and on to the waste ports, but that's where my imagination ran out since I'm not a rocket scientist nor do I play one on teevee
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The problem with blackout during a hot re-entry from orbit is plasma from the heatshield or tiles (in the case of the Shuttle) blocking radio signals at Mach 20 or so (about 6 km/second or thereabouts). This wasn't the case of the Falcon first stages as they were never going fast enough in the atmosphere to produce any plasma. If any of them had then the bottom of the stage would have melted since it's mostly lightweight low-melting-point alloys. Those sorts of temps would also have damaged a lot of the motors, the actuators, the guide fins etc.
As for the accuracy thing, again it was not a re-entry from orbit and the stage had guidance systems to bring it down to the barge, much as the Shuttle never had a problem finding the runway and painting the centreline during its landings. What puzzled me more was the speed at which the stage hit the barge. It should have been a lot slower, even with the failure of the guidance fins.
It's supposed to land like this:
https://www.youtube.com/watch?...
You know, vertical and stuff.
Think of it as evolution in action. You can stay on one planet while some disaster takes it out. We have lots of choices of disaster, don't we? The human race can continue via those "space nutters".
Sure, we should try to avoid the disaster, etc., but planets are not forever.
Bruce Perens.
You can choose a ready guide
In some celestial voice
If you choose not to decide
You still have made a choice
--Peart
They sang that lyric, but the printed lyric books read "You cannot have made a choice". I've always loved the fact that they described agnosticism both ways.
Socialism: a lie told by totalitarians and believed by fools.
I dunno, I'm happy enough with my voluntary free association with the United States. I'm free to leave if I stop liking it, as are you.
What anti-state people don't seem to grasp is that the very same people who you hate in the government, the people who want to control your life and take things from you, weren't made that way by big government. Just look at Mexico. Big drug cartels (who may or may not be entirely the creation of anti-drug big government) are more powerful than the government. Wherever there is an advantage to be had by banding together and robbing the weaker or more honest people, you'll find that niche being filled. The job of government is to fill that niche with the least harmful and most inept robbers. That overpaid, uncooperative, unfriendly civil servant that you despite? Give them a gun and a posse and see how well that turns out for you.
I mean, If it's already slowed down like this, why not just gently land the rocket into the ocean and take it up with some prepared nets/ropes? IMHO it can save a lot of headache from trying to hit a platform this small.
If the water getting in the rocket is problem, what about a gigantic sheet of plastic on the water surface? (still cheaper and more reliable than hitting the landing pad).
Wow, when Musk said that it was a "hard landing" I thought he may have been exaggerating, he wasn't. Though it was VERY close. If I'm not mistaken the rocket is oriented pretty well (though is off the landing pad) just before it suddenly goes 45 degrees (presumably in an attempt to get to the barge) and slams into the deck. A larger pad would definitely help, but they may be able to tweak the navigation software to make it work.
Elon stated while being questioned last week that the steering fins went hard-over (which means they were driven to their maximum angle) when the fluid ran out. With the fins pushing the rocket over, it didn't have much hope of landing. And, yes, a pressurized accumulator is the most likely design of this system.
/u/DixieAlpha over at reddit programmed a Kerbal Space Program model to try to land with grid fins fixed at 30 degrees. The results were scarily similar to this landing.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
The fact that the next launch was already going to carry 50% more fluid indicates that they had an idea that there might not have been enough. That decision about how much fluid was needed would have been made early on, and they could not have fixed it later, as this secondary experiment could not be allowed to interfere with the primary mission.
The engineers monitoring the landing would have seen the fins be driven to hardover and known instantly that they'd run out of fluid (if they didn't have a sensor for that). Elon tweeted that they'd run out of hydraulic fluid within hours of impact.
As others have stated, this was testing anyway.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
The initial reason for not releasing video was that it was dark and foggy, and the video was not fit to release. While this may have been more about controlling the news cycle by forcing the media to use pictures of the successful launch, it is clear that this video required a lot of levels adjustment to make it acceptable, and that has created noise in the image. However, apart from the drops of water on the lens, which is unavoidable, the quality is quite good.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
Those handful of cameras were either toasted, or the images were washed out by the glare and the mist. There were a good many cameras on the barge, in various places.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
Solid booster casings are a very different beast. A solid booster rocket needs to be very strong, because the combustion chamber of a SRB is literally the entire rocket. The whole thing needs to withstand combustion chamber pressure. So it is strong, tough (and heavy), so you can do what you like with it.
A liquid fuel rocket is a much more fragile beast. If allowed to tumble through the atmosphere, or hit the water at parachute speeds, it would be totally destroyed.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
They are using fuel as hydraulic fluid, an old and (apparently) still stupid idea. The SR-71 used JP-6 as fuel and hydraulic fluid -- one Habu pilot told me, "yeah, dumb engineering decision. If you are on bingo fuel, you might as well plan for a ditch, because bingo also means you are out of brakes and maneuvering." That was 35+ years ago. You'd think Elon would have covered that base.
The fault that caused this failure was the control fins running out of pressurized hydraulic fluid. When this happened, they were driven fully to one side, pushing the rocket over. The engine tried it's best to counter that, but it didn't have a hope.
A fellow fan tried something similar in the Kerbal Space Simulator. I imagine the real flight was very much like this:
http://gfycat.com/PointedWhisp...
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
Sure, that looks almost fixed. Kind of in the way PayPal is almost e-money.
Bob Stein, http://bobste.in
48% confidence that 2014 is the warmest year on record. (Straight from the 2014 NOAA state of climate report)
Warmest year on record, by 0.04C with an error margin of 0.09C (Seriously?)
http://wattsupwiththat.com/201...