SpaceX Rocket Launch Succeeds, But Landing Test Doesn't 213
New submitter 0x2A writes: A Falcon 9 rocket built by SpaceX successfully launched a Dragon cargo ship toward the International Space Station early Saturday— and then returned to Earth, apparently impacting its target ocean platform during a landing test in the Atlantic.
"Rocket made it to drone spaceport ship, but landed hard. Close, but no cigar this time. Bodes well for the future tho," Elon Musk tweeted shortly after the launch. He added that they didn't get good video of the landing attempt, so they'll be piecing it together using telemetry and debris. "Ship itself is fine. Some of the support equipment on the deck will need to be replaced."
"Rocket made it to drone spaceport ship, but landed hard. Close, but no cigar this time. Bodes well for the future tho," Elon Musk tweeted shortly after the launch. He added that they didn't get good video of the landing attempt, so they'll be piecing it together using telemetry and debris. "Ship itself is fine. Some of the support equipment on the deck will need to be replaced."
Volunteers needed (Score:2)
For the first manned landings
Re:Volunteers needed (Score:5, Informative)
There will never be manned landings of the first stage. Or the second. For the simple reason that there is no reason to man them in the first place. As for the crew capsule - well by then they will have had lots of practice landing the first two stages, not to mention the much more similar unmanned cargo capsules which are a much easier control challenge than the booster stages - compare balancing a vertical broom in your palm to balancing a baseball. It might get a bit more exciting if the crew were allowed to wander around during landing, chaotically modifying the mass distribution, but I suspect most everyone would rather be strapped firmly in place anyway.
Minor setback (Score:5, Insightful)
The fact that it made it to the platform itself is a major milestone, correcting whatever caused it to land hard (rough seas, hardware/software issue, ran out of fuel at the last second) would seem to be childs play compared to what was required to get to that point. Reentering craft usually have landing ellipsis of dozens if not hundreds of square miles and this thing landed on a 300'x170' platform. I look forward to the next (hopefully successful) test.
Re:Minor setback (Score:5, Insightful)
Re:Minor setback (Score:5, Insightful)
I assume that meant the boat was undamaged, not the rocket.
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Yeah, I'm assuming what this means is that it touched down too hard, one or more of the legs bent/broke and the rocket tumbled over. Or all legs didn't get on the platform and it tipped over. Hopefully next time there's a daytime landing, telemetry and debris will presumably give SpaceX what they need watching it would be way cooler.
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It will be interesting to see how "bad" this landing was... Was it a total, catastrophic loss, or did it just break a leg on landing and fall over onto the barge platform? The engines are the most expensive part of the "stack", and there are nine of them on the F9 booster stage. If they can salvage six or seven of these Merlin engines from this booster, even that will be a major victory.
Given the rate of innovation and development we've seen from SpaceX in the last few years, I suspect we'll see them nail t
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That they landed "well enough" to report the ship is fine means... well, pretty much nothing. It doesn't take much to damage the rocket, but it does takes a great deal to significantly damage a steel barge. (Think hitting a chunk of granite with a wineglass.)
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It tells us at least that the rocket didn't impact it moving at hundreds of meters a second. Sabot-launch a streamlined wineglass out of an high power air cannon at a chunk of granite and yeah, you'll almost certainly break off chunks of it.
We can say pretty assuredly say that it got to its final landing stage, was slowly lowering itself to the deck... and then "something" went wrong.
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Well, no - we can't say that. Why? Because we don't know that it was slowly lowering itself to the deck. It impacted at 12/ms, but that low speed could have been the result of a long deceleration burn *or* a last second suicide burn. (And in many ways, the second is often a better strategy.)
But you'd have to actually know something about the problem rather tha
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Grasshopper always did something roughly equivalent to a last second suicide burn, why would Falcon be any different? But that's "slowly lowering itself to the deck". Only for a brief moment, but the key is, getting the velocity down. It clearly had the velocity down. But something went wrong.
Re:Minor setback (Score:4, Insightful)
No, it tells us they got the Dragon down onto a 300x170 foot platform before things went south.
Personally, I'm impressed that the Dragon even found the landing barge on the first try....
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It wasn't the Dragon capsule, but the 1st stage of the rocket itself.
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Dragon, Falcon, all the same eh?
Seriously, not sure how I managed to put the wrong name on the rocket. My bad.
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That they made it this far and were most likely able to retrieve a ton of information for their people to improve the next attempt sounds to me as well like they got their money's worth.
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What they accomplished was absolutely amazing. Anyone who doesn't get how astonishing just getting that close really was doesn't understand the problem.
There has to be a test range on land somewhere they can try putting one down instead of a pitching platform in the middle of the ocean.
Re:Minor setback (Score:5, Insightful)
There has to be a test range on land somewhere they can try putting one down instead of a pitching platform in the middle of the ocean.
Not when you launch eastward from Florida.
A bit off topic (Score:2)
I have a semi-related questions – why not add wings and land the first stage like a airplane or done?
Is the extra weight for the fuel needed to land the first stage really that much less than the extra weight for wings? Even if the wings weighted more, I would think that the simpler design would win over. Of course, I am assuming that balancing a multi-ton pencil on a pillar of flame is hard.
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Adds a *lot* of extra drag and parasitic mass on the ascent. Still, the Russians planned to do that with the Baikal flyback booster: http://en.wikipedia.org/wiki/Baikal_%28rocket_booster%29. They may decide to revive it, given the apparent progress SpaceX is making...
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My guess is that folding wings & landing gear would be heavier and more difficult to produce. Also, it would mean you'd need a landing strip to land at, which would mean it would have to fly over land; probably a harder thing to get clearance for.
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There are some working on a similar concept (Stratolaunch, Russian Re-entry Rocket Module (RRM), defunct Roton Rocket). To each their own, I would imagine that SpaceX didn't want to try to mix disciplines (rocketry & aircraft) and add moving parts. You can't just put a wing on a rocket and launch it, doing so adds immense drag and difficult to resolve aerodynamic forces so they often have to be stowed/folded into the rocket somehow. The only craft that I believe has successfully added fixed wings is
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Maybe. While your points are valid, I would be careful about using the Space Shuttle as a key exhibit because it was the result of a stupid compromise.
The Space Shuttle was designed to land at the Vandenberg Air Force Base, which is much further north than Kennedy. In order to reach that far north the Space Shuttle needed a delta wing and had to come in screaming fast. The civilians at NASA would have preferred a straight wing. While it could not have reach Vandenberg, it was lighter and landing the thing w
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It also had to land fully-loaded, because the military wanted to be able to bring stuff back from space.
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I am assuming that balancing a multi-ton pencil on a pillar of flame is hard.
No doubt that it is hard, but the control system does not add a lot of mass or drag, so there's a big reward for figuring it out.
Re: A bit off topic (Score:5, Informative)
Putting wings on something that consists of empty tanks in front and heavy engines in the tail is harder. A rocket stage has totally the wrong center of gravity to fly this way. Try to throw a dart with the heavy tip backwards and you will see why.
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It is hard - extremely hard. Stability is only part of the problem, hover offers a lot of other problems that don't crop up when the craft is facing strong and roughly steady G forces. But landing like that gives mass benefits. And small mass benefits on one stage means very large benefits for your payload capacity delivered to space. So if you can pull it off, it's a big win.
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I don't think the fuel is "extra"... I think it is safety margin fuel that would otherwise be wasted. Remember that this thing has to be able to make it to orbit even with the loss of an engine or two.
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But rocket science isn't exactly brain surgery.
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This was the first flight with the maneuvering grid fins. The fact that they were able to bring the rocket to the barge with an untested maneuvering technology is quite remarkable. It speaks volumes to their modelling software. I can speculate that because of the untested grid fins, the maneuvering was not quite as precise as needed and the rocket engines had to do a large slew just before landing, which burned up too much fuel. My speculation is that the fuel ran out just before landing.
The fact that
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If it was a fuel issue it could explain something. I've never seen a fuel tank camera before (though I am sure they have been flown before) yet at least the video I watched they gave a view of the second stages fuel tank (I believe) for quite a while after ending the burn. I wonder if they were trying to show the NASA guys that they could stage the rocket a little earlier (leaving more fuel in the first stage) due to an ample safety margin (there seemed to be quite a bit of fuel left.)
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It wasn't fine, it was destroyed in the landing. The ship it landed on is fine.
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Every first stage ever made and flown has been simply thrown away after one use. FIrst stages are quite a bit different from whatever is on the top of the stack.
For that matter, "lander on legs" is a different thing on Earth than it is on the moon or Mars.
I will agree that there is a decided anti-NASA attitude around here, though.
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Every first stage ever made and flown has been simply thrown away after one use.
Neglecting the space shuttle, of course. And to be fair, even that threw away the fuel tank, which IIRC cost $50 million.
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I liked David Brin's "Tank Farm Dynamo", which featured a space station made from used external tanks. Part of the premise was that ETs were deliberately discarded the way they were, so that they'd burn on reentry and not become space debris. For negligible cost they could be brought the rest of the way to orbit, available for use there.
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For negligible cost they could be brought the rest of the way to orbit
I doubt the cost was negligible. However I remember the original plans to use those tanks for stations etc. A shame we did not leave them in orbit, imho.
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The space shuttle fuel tank was not quite in orbit yet, so it would have taken extra fuel to get it there. And if you park it in a low orbit, it needs regular boosts to compensate for the atmospheric drag. But what good would it do to keep an empty fuel tank in orbit ?
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The idea was to shoot them into a higher orbit.
That is why I contradicted the idea of the parent that it would be cheap in fuel, as I believe it would need a quite a bit.
The idea was you could later combine several of them to form what is now the ISS, or similar stations.
Of course thinking about it, perhaps they figured that an empty tank makes perhaps a hull, but putting the equipment inside in space might be more challenging than building the modules on earth and shoot them up.
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But what good would it do to keep an empty fuel tank in orbit ?
Especially one that's covered in foam that's off-gassing, and shedding small bits and pieces over time. Also, never mind the fact that the tanks were built as thin and as lightweight as possible, so had they been pressurized and converted into living spaces, they would have provided little to no shielding against space debris or radiation. Also, never mind the fact that by definition they were almost empty after launch, so you would still need to haul up all the fittings, equipment, furniture, etc... that
Re: Minor setback (Score:5, Informative)
Landing *anything* that's been to space on a barge has never been done before.
Landing a full-size *first stage* that's delivered a payload to space *anywhere* has never been done before (far, far harder problem than landing a crew capsule, they're massive, hard to control, and imbalanced).
The thing is nearly as heavy as the Space Shuttle, much larger, a much more unstable shape (due to the nature of rockets), has only stubby grid fins for manueuvering, is controlled by a computer with no ability for real-time corrections by a pilot, and was landing on a barge barely larger than itself. And was created on what's by comparison a shoestring budget. Let's not pretend that this isn't a massive challenge.
I know it's the nerd-equivalent of being a hipster to berate anyone who expresses any support for SpaceX, but for god's sake, look objectively at the nature of this challenge for a minute. One can hate Elon, but these engineers are not exactly picking the low hanging fruit, and they've still achieved very impressive results thusfar.
(The real question will be, of course, whether they can actually refurbish these first stages cheaper than they can build them... most people assumed the Shuttle would be dirt cheap to refurbish, after all...)
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...SpaceX being a private entity, they just have a lot of paid PR people to drum up support.
I'm sure this is true. And their enemies in the military-industrial complex (Boeing/Lockheed Martin/ULA) have deep pockets to hire propaganda companies to slander SpaceX. In fact, they already have. Look at the client list of this PR (propagandistic relations) company called Shockey Scofield Solutions [s-3group.com].
Reading between the lines, I think this is a company that specializes in greasing palms/pulling levers in Congress and the Senate, as well as constructing sophisticated internet campaigns that include re
What floated by the Dragon's solar panels? (Score:2, Interesting)
About 10 minutes and 15 or 20 seconds after the launch, a camera was showing the backs of some solar panels of the Dragon. At that time, it looked like something floated to the upper left, and then floated out of view. The thing was light-colored, and it looked like it was tumbling. Does anyone know what that was? A piece of paper?
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Probably just a flake of ice, the rocket/spacecraft are generally covered with it on launch and if you look closely it sheds it throughout the flight.
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My thoughts as well but it's still surprising a chunk of ice would still be on the vehicle after it went supersonic.
That's a hell of a lot of friction.
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The primary buffer panel?
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Probably a cover (either foil or tyvek, not sure what they use) that covers over the RCS jets while the rocket launches, then is discarded when the jet is first fired. A similar thing was occasionally seen on shuttle launches. These covers are there to keep crap (both bird, and rainwater etc...) out of the jets while the rocket is sitting on the pad.
it made it home (Score:5, Insightful)
Well, I think it's a milestone. Just getting it to land on the platform, in the dark, without any human help. That speaks a lot of the hard work that people invested. So it gets some damage, big deal.
I am glad that it was not a total success, otherwise people might get into lazy thinking and not look for bugs. I believe (not sure, cannot cite sources on this), but some airplane was not tested enough because everything happened perfect on testing, it was placed into production (1950's). Over the course of a year or 2, the planes were having issues and a few crashed. And they had to stop production. Some sort of fault in the structure.
So, in summary, He's done it!!! now to get all the bugs worked out.
Re:it made it home (Score:5, Informative)
Sounds like the aircraft you are describing is the De Havilland Comet, http://en.wikipedia.org/wiki/D... [wikipedia.org]
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thank you
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Well, I think it's a milestone. Just getting it to land on the platform, in the dark, without any human help.
What is all that special about landing in the dark? You do realize we have all sorts of cameras that can "see" in the dark, right?
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What is special about landing in the dark... hmmm.
a) Depth perception in darkness changes (given they could use some sort of sonar type bounce to get a distance reading)
b) Blindness of the camera's when the thrusters are activated.
c) Landing on the water, barges move up and down, that's really impressive, it's only so stable. This is nothing like a carrier landing in any way.
Well anyway, I am amazed and cheering for them!!!
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a) Depth perception in darkness changes (given they could use some sort of sonar type bounce to get a distance reading)
There are all sorts of sensors and readings to use to land in the dark especially when automated. You do realize that planes fly all the time in the dark and in fog, right?
b) Blindness of the camera's when the thrusters are activated.
You wouldn't be using only cameras. You would have a host of other sensors to provide all manner of positional information. None of this is new or impressive.
c) Landing on the water, barges move up and down, that's really impressive, it's only so stable. This is nothing like a carrier landing in any way.
Sure, that is impressive, but has nothing to do with being in the dark. Such a thing is tricky regardless of the amount of light.
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>>You do realize that planes fly all the time in the dark and in fog, right?
Yes, I do and that's with humans at the stick, but the plane can land itself. on a stable platform ( runway ) that has know variables, big space, a performance design that have been tested and tested and updated almost to the point that it's automated, but at the end, a pilot is still required just in case. Landing and takeoffs are still the highest risk points of a flight.
But this landing, this is a tiny little speck, and i
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You're probably thinking of the Comet - the problems were less ones of
New meaning (Score:2)
No video? (Score:2, Redundant)
Come on, didn't they learn their lesson trying to reconstruct video to analyze earlier water landings? Here you've got a big frigging barge that they expect to be ground zero for an important rocket crash - I would have expected them to mount a few automatic cameras on nearby buoys so they'd be sure to get multiple videos of the crash to learn as much as possible
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"...pitch dark and foggy..."
And a real pity no technology exists to illuminate a scheduled landing to allow clear recording by the cameras that were deployed.
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Hey, give 'em a break. They have to launch at exactly the right moment to catch ISS, and today's moment was simply too early to have any sunlight there. The dense fog didn't help either. On the other hand, it didn't land in the water, so they can finally take the SD card out of the GoPro in the rocket!
I just want to see a picture of rocket bits on the barge, broken or not.
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The guys at http://www.reddit.com/r/spacex [reddit.com] have been following the Autonomous Spaceport Drone Ship (That 'Drone' really helps with the abbreviation) from a cruise ship that has a webcam pointed in its general direction when it's in port, hopefully we'll get a glimpse of it when it gets back.
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Yeah guys, it's early in the sequence. They may well have low light / infrared cameras pointing at the thing. They probably don't have cameras hovering around waiting to transmit from the middle of nowhere in realtime. Further, most IR cameras have reduced spatial resolution compared to visual range so they may have decided that the investment in time and money wasn't worth it. The telemetry will show the engineers the important stuff. He's not doing this to make YouTube videos.
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It is inconceivable that they didn't have cameras all over the barge. The problem is that SpaceX is on track to put all of its competitors out of business and they will seize on any scrap of "evidence" to trot in front of Congress to claim that their rockets are dangerous. The 50% odds of success Musk claimed were probably bogus too but a necessary lie to keep the detractors at bay.
No KSP at SpaceX? (Score:2)
Re:No KSP at SpaceX? (Score:5, Informative)
Firstly, I think SpaceX were trying to get away from parachute recoveries. The Shuttle solid booster rockets used to parachute down into the ocean, but the problem with that is that they need completely cleaning out and refurbishing between each flight.
Secondly, they would need more than parachutes to recover the first stage because it is travelling so fast when it separates (not sure of the exact number, but somewhere between 2 and 4 Kilometers per second). They have to do a retrograde burn to slow down enough to safely re-enter the atmosphere.
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They already tried that more than once. It did not work well. The impact on landing is too large. You need the retro-rocket burn.
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I've heard that parachutes are fairly expensive, not horribly reliable (on the Ares-1x test flight 2 out of 3 failed), aren't really reusable and don't really decelerate spacecraft enough for a soft landing. There is a reason why most capsule spacecraft land in the ocean, landing on ground requires retrorockets.
In other words ... (Score:2)
The operation was a success but the patient died.
Twitter: Ran out of Hydralic fluid (Score:5, Informative)
Elon Musk @elonmusk "Grid fins worked extremely well from hypersonic velocity to subsonic, but ran out of hydraulic fluid right before landing."
"Upcoming flight already has 50% more hydraulic fluid, so should have plenty of margin for landing attempt next month."
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Telemetry by its very definition is transmitted to a remote monitoring station... the word literally means "remote measure". They didn't have to "recover" it (like a physical airplane flight data recorder or something).
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The only way hydraulic fluid can be "used / lost" is if the vehicle had a major rupture in a hydraulic fluid line
True only if the hydraulic system is closed. Apparently that's not the way it's done in rocketry [twitter.com]: "Chris (Robotbeat) (see robotbeat@ comment).
and that will affect the landing gear (only item that can potentially use hydraulic fluids)
The grid fins are hydraulically actuated.
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Elon Musk @elonmusk "Grid fins worked extremely well from hypersonic velocity to subsonic, but ran out of hydraulic fluid right before landing."
"Upcoming flight already has 50% more hydraulic fluid, so should have plenty of margin for landing attempt next month."
That's odd, does anyone know why it would run out of hydraulic fluid? Usually a hydraulic system is a closed loop, are they constantly dumping hydraulic fluid from this stage?
Re:Twitter: Ran out of Hydralic fluid (Score:5, Informative)
Not an official reply but answered on Twitter [twitter.com]:
Chris (Robotbeat) @Robotbeat 3h3 hours ago
@dtarsgeorge @rocketrepreneur In aerospace, hydraulics are pressurized with gas (no pump) and no return lines. Pretty standard, actually.
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Aren't hydraulics that are pressurised with gas actually pneumatics?
Reinventing the wheel -- Am I missing something? (Score:2)
Re:Reinventing the wheel -- Am I missing something (Score:4, Informative)
Yes, that's exactly what they're doing. No one has soft-landed the first stage of a rocket after using it to launch something into orbit before. That stage normally burns up on reentry or is debris in the ocean.
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Sorry to burst your bubble. Other countries (ie: Russia) have already done a barge landing successfully .... but abandoned the idea because it wasn't cost effective.
Not of a first stage.
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NASA has used parachutes for rentry. Several new technologies [wikipedia.org] needed to be developed and tested to facilitate successful launch and recovery of both stages of the SpaceX reusable rocket launching system. Following the completion of the third high-altitude controlled-descent test, and the completion of the third low-altitude flight of the second-generation prototype test vehicle (plus eight flights of the first-generation Grasshopper prototype flight test vehicle), SpaceX indicated that they are now able to
what about a net? (Score:3)
Honest question, I'm no rocket scientist so I really don't know: Since they seem to be able to hit the mark, why not just put a big net on the drone ship to 'catch' it rather than try to land it on legs?
Actually it was a MAJOR partial SUCCESS ! (Score:3)
There were two goals far more important than actually recovering the first stage:
1 - Having the stage navigate to the landing pad. It would have been a major failure if the rocket landed 2 miles away and were fished out of the water.
2 - Not destroying the landing barge (its worth far more than the first stage, and it would take a few months to prepare another one).
Additionally, in less than 24 hrs SpaceX already knows what went wrong, have a fix for it, and intends to try again on the next launch (about 3 weeks from now, end of scheduled for January).
So, calling it a failure is like saying this glass is 10% empty !
SpaceX has already managed to have the rocket hover for a second or two meters from water, but back then there were no precision in where the rocket was aiming to splash. The difference is many changes were made to the rocket to steer it.
SpaceX might have a dozen shots at trying this in 2015 alone.
Re:No good video? (Score:5, Informative)
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I can just imagine what a rocket looks like on IR.
I'm going to assume either all white or all black, depending on polarity settings.
Re: No good video? (Score:5, Informative)
Another news story said it was foggy and zero visibility. The cameras on the rocket really only showed anything when it fell over into the water, where bubbles could be seen.
Considering spaceX has navigated the rocket exactly where they wanted every landing attempt, I wonder when they will finally get permission to land on, um, actual land. For all we know the ship may have pitched up increasing the velocity that the rocket touched down. Plus I'm sure the poor visibility at sea couldn't have helped either.
Re: No good video? (Score:5, Informative)
The bubbles you're probably referring to were from a camera inside the liquid oxygen tank of the second stage.
https://www.youtube.com/watch?... [youtube.com]
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Considering spaceX has navigated the rocket exactly where they wanted every landing attempt, I wonder when they will finally get permission to land on, um, actual land. For all we know the ship may have pitched up increasing the velocity that the rocket touched down. Plus I'm sure the poor visibility at sea couldn't have helped either.
Unless there was a huge storm in the area I doubt a 300'x170' barge has much of a pitch and in that case the rocket would probably be much worse off than the barge. And the telemetry shouldn't be much affected by dark and fog, just the cameras. To compare with airplanes I understand category IIIb airports are fairly routine now which means zero visibility landing, 150 feet runway visibility range. And that's basically just so they won't bump into each other while taxiing, zero RVR is possible but would requ
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All we can say is, if the ship is fine, just some equipment damaged on deck, then this was a very low speed impact. Sounds more like the rocket falling over than anything else. Why? Not a clue. But I guess we'll find out. Maybe Musk's plan of "have it weigh itself down and then we'll weld it to the deck afterwards" wasn't a good one.
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300 x 170 is a real bad ratio, it's going to be a sloppy ride. A good stable ratio is in the 30 x 5 x 3 ( L x W X H ). I got to assume he knows something or the barge design is amazingly special
dry bulk cargo barges are about 195' x 35' ( which is near the 6 x 1 ratio ) https://en.wikipedia.org/wiki/... [wikipedia.org]
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300 x 170 is a real bad ratio
Why do you consider the ration 'bad'? IMHO the ratio does not matter at all, the barge only needs to be big enough to provide the landing space and what ever else they need on it.
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>>
Why do you consider the ration 'bad'? IMHO the ratio does not matter at all, the barge only needs to be big enough to provide the landing space and what ever else they need on it.
Vessel stability on all 3 axis, I would guess that something like this needs a really good stable landing platform. It's not easy to keep a platform at the required location. I am going to take a guess that they tested everything to the extreem and this is what they came up with.
but the most likely size should have been nea
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That thing is not a "moving" barge.
It is only a barge in name. A better name perhaps would be "floating platform" or pontoon.
So it is pretty stable anyway. Your concerns make no sense to me.
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The larger the frontal surface area of the vessel, the harder it is to control. Wave motion and tidal forces become more pronounced as the vessel gets wider, making it harder to hold position.
This "barge" isn't a standard cargo hauler, though. You can see a photo of it at the link below. It was definitely custom-built for this purpose.
http://www.spacex.com/sites/sp... [spacex.com]
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A) Thanks for the photo. That explained a ton.
B) In vessel design, some basic ratio's are used, and stability is important. The dimensions just don't add up to be any good if it's a barge, the roll and pitch just seem way out of line for such a box type shape. Pontoons on the otherhand, they overcome ( better word is reduce ) multiple stability problem.
so maybe it's a pontoon type platform, all I got is an overhead shot ( which I thank you for )
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300 x 170 is a real bad ratio, it's going to be a sloppy ride. A good stable ratio is in the 30 x 5 x 3 ( L x W X H ). I got to assume he knows something or the barge design is amazingly special
dry bulk cargo barges are about 195' x 35' ( which is near the 6 x 1 ratio )
I have no idea what you're hinting at, a few quick searches indicate that the narrower beam (width) the less stable it gets. The shape of your average barge seems more about being able to traverse waterways and efficient loading/unloading at docks, for optimal stability it should probably be square with as low a center of gravity as possible.
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First off, where did you get the impression that Musk said anything like that? Secondly, where did you get the impression that the person you're replying to said anything like that? They never said "land at the same place".
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They never said "land at the same place".
Yes they did. Landing at the launch site is the planned final goal.
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[Citation needed]
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Environmental assessment for their landing sites at LC13 at the Cape:
http://www.patrick.af.mil/shar... [af.mil]
Return to launch site has been their goal all along. It's only in the last few months that they started talking about the seagoing landing platform approach, and then only for those situations where there wasn't enough propellant left to return, which were previously expected to require more expensive launches that expended cores instead of recovering them (the Falcon Heavy center core and geosynchronous la
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The mission is to deliver cargo to the ISS for their client, NASA.
Landing the first stage is a separate internal goal and the data they got from this attempt is progress towards that goal.
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The difference is that for the manned flights you've mentioned, returning the astronauts back to earth was part of the primary objective and they wouldn't have launched if they didn't have a high likelihood of accomplishing it.
The goal of SpaceX Falcon 9 launches is to deliver cargo to orbit, once that is accomplished the mission is a success.
The fact that they can use the spent first stage of the rocket for development testing towards developing reusability instead of just letting it splash down into the o
Re:Strange definition of success (Score:4, Insightful)
They have a long-term goal of full reusability for their spacecraft, starting with the most expensive part of the launch, the first stage booster. Because every other launch in the history of rocketry has involved the destruction of the first stage, they build the cost of losing the first stage into the total launch cost. (The space shuttle's boosters parachuted back to Earth, but were not reusable - just parts of them, and only after a great deal of costly refurbishment.) Each attempt to land the booster is an experiment at this point, which has the benefit of being a freebee, as the booster has already been paid for. Attempt one spun out of control, but they got good data, understood the problem and adjusted. Attempts two and three had the booster vertical and hovering over the ocean. This was 100% success, as there was no more optimal outcome for the experiment. However, the landing point was not a precision target, but a 10 sq km range. On today's first attempt to land on a solid surface, they had to land with extreme precision, which they did successfully, but came down too hard. These are experiments, so each step forward, as long as the failures produce actionable data, can be deemed a success.