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SpaceX Rocket Launch Succeeds, But Landing Test Doesn't
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."
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.
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?
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.
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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.
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According to Elon "Didn't get good landing/impact video. Pitch dark and foggy."
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.
Better known as 318230.
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...
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.
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?...
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 require lots of instruments from runway to the gate and in most whiteout conditions you wouldn't want to be flying anyway because of the winds, not the visibility.
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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.
Faster! Faster! Faster would be better!
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."
Today's vices may be tomorrow's virtues.
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.
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.
Maxim: People cannot follow directions.
Increases in truth directly with the length of time spent explaining them
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?
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Not an official reply but answered on Twitter:
Chris (Robotbeat) @Robotbeat 3h3 hours ago
@dtarsgeorge @rocketrepreneur In aerospace, hydraulics are pressurized with gas (no pump) and no return lines. Pretty standard, actually.
Live today, because you never know what tomorrow brings
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: "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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You may not have been following what SpaceX is trying to do an the methodology to get there. The mission is to resupply the ISS, which looks to be a 100% success for the fifth time, pending a safe docking on Monday. They also have returned a payload of cargo to return to Earth safely four times. The Progress Raduga capsule can only return 150 kg of cargo, where Dragon can return 2500 kg, pressurized. They are doing all of this at a much lower cost than the competition. This is the mission and they have been 100% successful with Falcon 9 v1.1 every time.
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.
Environmental assessment for their landing sites at LC13 at the Cape:
http://www.patrick.af.mil/shar...
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 launches, mainly).
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.