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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."
No good video? In the era of rocket cam? He should say, no video he wishes to show. Elon Musk is a master propagandist.
an ill wind that blows no good
For the first manned landings
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.
if you see me, smile and say hello.
New meaning to "Hit the deck!" Or "Incoming!" Perhaps they should rename the barge to "Oh fuck!" Seriously, congrats though SpaceX
Here's to losing my Karma Bonus again....
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
--- Most topics have many sides worth arguing, allow me to take one opposite you.
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.
One of the first contracts in KSP career mode gets you to save one stage with parachutes, maybe SpaceX should look into something similar..
There are no atheists when recovering from tape backup.
The operation was a success but the patient died.
Today's vices may be tomorrow's virtues.
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.
The fact that he can make this claim only half a day after the fact (so I assume they had no time to piece together the debris) means that they did recover the most valuable part: the telemetry. Overall, they achieved probably 95% of the required challenges. With around 5 successful retro burns, 1 low-level flame out due to loss of roll control, 2 soft water landings, 1 bullseye impact on a boat and around ten successful low altitude tests with grasshopper, only extremely bad luck can stop them from making a good landing in the next few attempts.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
Is SpaceX accomplish something that hasn't been done by NASA? I don't understand all the excitement over landing a rocket when it has already been done so many times before? Am I missing someone?
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
NASA has used parachutes for rentry. Several new technologies 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 consistently "reenter from space at hypersonic velocity, restart main engines twice, deploy landing legs and touch down at near zero velocity."[29]
The technologies that were developed for this program, some of which are still being refined, include::
restartable ignition system for the first-stage booster[17] Restarts are required at both supersonic velocities in the upper atmosphere—in order to decelerate the high velocity away from the launch pad and put the booster on a descent trajectory back toward the launch pad—and at high transonic velocities in the lower atmosphere—in order to slow the terminal descent and to perform a soft landing.[30]
new attitude control technology—for the booster stage and second stage—to bring the descending rocket body through the atmosphere in a manner conducive both to non-destructive return and sufficient aerodynamic control such that the terminal phase of the landing is possible.[30] This includes sufficient roll control authority to keep the rocket from spinning excessively as occurred on the first high-altitude flight test in September 2013, where the roll rate exceeded the capabilities of the booster attitude control system (ACS) and the fuel in the tanks "centrifuged" to the side of the tank shutting down the single engine involved in the low-altitude deceleration maneuver.[21][31] The technology needs to handle the transition from the vacuum of space at hypersonic conditions, decelerating to supersonic velocities and passing through transonic buffet, before relighting one of the main-stage engines at terminal velocity.[19]
throttleable rocket engine technology is required to reduce engine thrust because the full thrust of even a single Merlin 1D engine exceeds the weight of the nearly empty booster core.[32][33]
terminal guidance and landing capability,[13] including a vehicle control system and a control system software algorithm to be able to land a rocket with the thrust-to-weight ratio of the vehicle greater than one,[34] with closed-loop thrust vector and throttle control[35]
navigation sensor suite for precision landing[30][36]
lightweight, deployable landing gear for the booster stage.[10] In May 2013, the design was shown to be a nested, telescoping piston on an A-frame. The total span of the four carbon fiber/aluminum extensible landing legs[37][38] is approximately 18 meters (60 ft), and they weigh less than 2,100 kilograms (4,600 lb); the deployment system uses high-pressure Helium as the working fluid.[39][40]
hypersonic grid fins were added to the design beginning on the fifth ocean-descent test flight. Arranged in an "X" configuration, the grid fins control the descending rocket's lift vector to enable a much more precise landing location.[41]
a large floating landing platform in order to test pinpoint landings prior to receiving permission from the US government to bring returning rocket stages into US airspace over land. In the event, SpaceX built the Autonomous spaceport drone ship in 2014,[42] and intends to conduct an initial flight test and landing attempt in January 2015.[43]
large-surface-area thermal protection system to absorb the heat load of deceleration of the second stage from orbital velocity to terminal velocity[30][44]
Today's vices may be tomorrow's virtues.
The previous landing tests (on the ocean surface, without actual landing platform) did not use the steering fins, and had a landing accuracy in the order of 10km. Hitting the ship is a _huge_ improvement in accuracy, even if it was just outside the new 10m error margin.
Slowing the rocket down to 0 speed at 0 altitude is also very tricky. The engines can only be throttled down to 70% of there max power, so even with one of the 9 engines, the minimum thrust is more than the weight of the (empty) first stage. Start the landing burn too soon, and the rocket will go back up before reaching 0 altitude, start the landing burn too late and you won't reach 0 speed before reaching 0 altitude.
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).
"Mind, as manifested by the capacity to make choices, is to some extent present in every electron." -Freeman Dyson
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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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?
Enigma
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.
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.
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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 ocean is a bonus.
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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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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They're using the fuel/oxidizer as their source of hydraulic fluids.
Propellants are fed via a single shaft, dual impeller turbo-pump. The turbo-pump also provides high pressure fluid for the hydraulic actuators, which then recycles into the low pressure inlet. This eliminates the need for a separate hydraulic power system and means that thrust vector control failure by running out of hydraulic fluid is not possible. A third use of the turbo-pump is to provide power to pivot the turbine exhaust nozzle for roll control purposes.
Ironically, they didn't have a thrust vector control failure, but a control surface failure... by running out of hydraulic fluid. I think they'll dial it in for the next one, though.
You seem to mix up two things here - the Dragon Spacecraft is currently in orbit - that is the part that is going to return with either cargo or crew back to earth at the end of the mission. What landed/tried to land today is the first stage of the ROCKET, not the mission spacecraft. The rockets so far have always been throwaway and crashed in the ocean or somewhere with low population after they boosted the second stage with the spacecraft. the goal here is now to recover the first stage and reuse it - something that has never been done by anyone, be it NASA or anyone else. NASA returned and reused the boosters on the space shuttle via chute and splashdown, but they had to be extensively rebuilt each time due to salt water corrosion. spaceX is currently doing something amazing that has never been done before with so much ambition, that's why everyone is looking forward to them succeeding.
Aren't hydraulics that are pressurised with gas actually pneumatics?
"It's such a fine line between stupid and clever" -- David St. Hubbins, Spinal Tap
Elon Musk @elonmusk Hydraulics are usually closed, but that adds mass vs short acting open systems. F9 fins only work for 4 mins. We were ~10% off.
Today's vices may be tomorrow's virtues.
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.
Not when the gas stays in the tanks (at least until the liquids run out) and the liquids do the actual work.
How is the Riemann zeta function like Trump rallies? Both have an endless number of trivial zeros.
No. By that theory hydraulics that are pressurized by a pump should be called mechanicals. They are called hydroponics because fluid is used to move actuators. It does not matter what produces the pressure.
@alankerlin Hydraulics are usually closed, but that adds mass vs short acting open systems. F9 fins only work for 4 mins. We were ~10% off.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
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.
So they landed a second or third stage for the hell of it???
AFAIK, they've only landed a capsule. If you have a citation showing something else, I'd love to see it.
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[citation needed]
Really, this is just utter troll talk here that shows you don't know what you are talking about. That SpaceX keeps pushing the envelope is true, but they've definitely delivered payloads to the desired location in orbit on multiple occasions, including 100% of the primary payloads on the Falcon 9. That they might have set some additional goals on each mission to go beyond the bare minimum expected and then fail on some minor point only goes to show that they aren't trying to stay safe either.
There was the DC-X program that tried to do mostly the same thing that SpaceX is doing here with this barge landing, but the DC-X never made the trip into orbit and only did pretty much what the Grasshopper did earlier. The DC-X was supposed to lead to a rocket that went into orbit and could be similarly reusable, but funding for that program was cut during the Reagan administration. Surprisingly, it is Blue Origin that purchased all of the IP rights to that technology and not SpaceX... but that is another story.
Wow, you're a special kind of dense, aren't you?
Columbia and most of the Apollo flights were manned. Calling safe return "just an internal goal" is not only moronic, it's flat-out wrong in the case of Apollo:
JFK (emphasis mine), 25 May 1961, http://www.jfklibrary.org/JFK/...
Second, you seem to be deeply confused (or trolling) about the difference between a space vehicle and a launch system. Dragon is a space ship, a "vehicle"; it carries stuff. The Dragon 2 (Crew Dragon) will carry people. It is, obviously, of critical importance to return them safely. Falcon 9 first stage isn't even an entire launch system, just the most expensive part of one (the first stage). A spent first stage is a like a (really expensive) spent bullet cartridge; sure, you save money on future shots if you collect it and re-use it, but the goal of any given shot is to fire the bullet and hit the target. Similarly, the goal of a Dragon/Falcon 9 launch is to put Dragon in orbit, and recover it safely.
In fairness, it's inaccurate to say that the CRS-5 mission is successful yet. Dragon hasn't even berthed with the ISS yet, much less returned safely to Earth. That doesn't seem to be your objection at all, though.
There's no place I could be, since I've found Serenity...
The AC's claim was that "other countries (ie: Russia) have already done a barge landing successfully". As I understand it, Russia has landed capsules, but on land not on a barge, and nothing as big and difficult to control as a first stage.
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I agree that the AC was simply showing a lack of knowledge about the topic. Russia is the world leader in propulsion technology (the next generation engine called the Raptor that SpaceX is building is based upon Russian technology), so I wouldn't dismiss Russia at all in terms of spaceflight technology on any level. None the less, there have been some other attempts by people other than SpaceX to get a reusable flight vehicle to do a controlled landing.
There are also some scholarly papers that have attempted to prove that what SpaceX is doing here is technologically impossible as well, trying to demonstrate that reusable systems for stage recovery will eat up all of the payload mass making such a rocket useless on a practical level. I believe some Russian propulsion scientists were involved in one of those papers that included some hardware tests. Seeing a rocket stage successfully deliver a payload to the ISS of several metric tons of cargo and land in a near-miss but for the want of a couple gallons of hydraulic fluid sort of shows that those papers might not be entirely accurate or at least there might be ways to reduce the mass of such recovery systems and still deliver a practical payload into orbit.