Slashdot Mirror
SpaceX Dragon Launches Successfully, But No Rocket Recovery
New submitter monkeyzoo writes: SpaceX has successfully launched a Falcon 9 rocket carrying a SpaceX Dragon spacecraft en route to the International Space Station with supplies (including an Italian espresso machine). This was also the second attempt to land the launch rocket on a barge, but that was not successful. Elon Musk tweeted that the rocket landed on the recovery ship but too hard to be reused. Video of the launch is available on the SpaceX webcast page.
What the Slashdot summary states:
"...the rocket landed on the recovery ship but too hard to be reused"
What Musk actually tweeted:
"Rocket landed on droneship, but too hard for survival."
Not being reusable and not surviving have different meanings.
Musk tweeted here that the rocket landed fine but there was residual lateral velocity that tipped it over after landing. The photos on that tweet are worth looking at.
Obviously, now they have to work on fine positioning with elimination of lateral velocity before it comes down on the barge. Not an easy problem, especially given that the first stage doesn't have much Delta-V in its cold gas reaction control thrusters and does most of its positioning with the grid fins and the engine. Which means using more fuel. Hopefully there's enough, or room for building up the RCS.
Bruce Perens.
I was hoping the rocket would be recovered this time. I'm hoping they will release the video like last time, and we can see what happened. The rocket recovery was the most exciting aspect of this launch. (Apart, of course, from the espresso machine. Ha ha.)
Here's the video. I like how they called it a RUD (Rapid Unscheduled Disassembly)
It failed less than the first attempt did. I don't like extrapolating from two sample points, but this does suggest improvement. Perhaps attempt three will get it right.
The first one hit hard and sank into the water.
The second one touch down fell over and sank into the water.
I predict the third one will burn down, tip over, then sink into the water.
But the fourth one, that will stand!
Microsoft, Apple, Google, Amazon what's the difference? All steal money from devs and control with walled gardens.
Unless its absolutely calm, how can you not get lateral motion, maybe shooting nets over top from each corner to secure it? Other suggestion was the 1000hp thrusters on the barge, this would be like balancing a broom handle in your hand, standing on a ball.
This is an achievement. Take it from an old rocket grognard, a veteran of Amroc, Orbital, and others: just getting this far is an accomplishment.
And it's smart of Musk to append a test operation onto a paying mission. The launch fee for the ISS delivery offsets a major portion of the cost of the test.
And in a test sequence, close does count, because all data gathered is useful. And often, data from a failure is more useful than data from a success.
"Success is a lousy teacher; it seduces smart people into thinking they can't lose." —Bill Gates
I can see the fnords!
why softlanding, why not just to parachute them like Zenith first stages? That scheme worked quite well for Ukraineans.
They should team up with ArmadilloAerospace or Masten (http://lunarlander.xprize.org/).
After all, they are all ex-computer geeks. They just need to debug some more.
And then the spankings shall begin?
Please! This is supposed to be a happy occasion. Let's not bicker and argue about what crashed when.
After the last one he said "the next one will also explode, but for a different reason". Dammit, I want explosions!
My Dads last job was to track the Shuttles solid fuel boosters and when the parachutes didn't deploy properly, best he could do is mark where they entered the water at.
Hopefully, each of these experiments is providing the data to refine a simulation of the landing sequence.
Once this sim has sufficient fidelity, they should be able to fly many virtual landings until they get it right every time.
If they can get to the state where real and virtual match and virtual is robust, they are there.
The question from this flight is what did they learn? ;-)
( And is the barge still floating for the next try
I still vote for a 6-dof ring on the barge which reaches out and grabs the tail once position and velocity get close enough.
This lowers the requirement for delta-v on the vehicle for the final, precision set-down.
Also, the ring can somewhat decouple the barge movements from an inertial reference.
Keeping the barge simple until they get to where the ring had good odds seems wise.
Keep it up guys. Persistent progress will get there.
Looks like there is a rough video of today's failed landing now...
https://t.co/4Te0BfT2Qn
The fourth was the biggest one they built, but it disappeared 24 hours after going online.
Two attempts and both of them at least hit the barge, even if they can't actually soft land on the barge they're well on their way to proving that they can at least land within a few hundred feet of their target. And if they can do that they probably only need a larger landing area, say a large parking lot, for a successful landing. The tests in Texas have proven that the rockets can have a controlled decent, just a few more kinks to iron out.
Seriously, how is this guy not president??
How is that remotely the same thing? The shuttle boosters weren't guided, weren't in powered flight, weren't re-lightable, weren't targeting anywhere terribly specific, weren't trying to make a vertical landing, and were designed for a water landing. None of that applies to the Falcon 9 first stage. Also, the F9 recovery system didn't fail to deploy, it simply didn't fully correct for the rocket's motion. Considering that the booster is basically an inverted pendulum and that there's almost always some lateral winds at sea, getting as close as it did is damn impressive and really not comparable to losing one of the Shuttle's SRBs.
There's no place I could be, since I've found Serenity...
So apart from the in-flight power, the relight, the targeting, the vertical landing, and the water landings, what's the difference?
I just saw the video. The weather conditions were perfect. But the attempt was not even close. Way too many large corrections at low altitude. The control system needs a great deal of work. SpaceX is not ready. I was disappointed Commissar Musk cut the video off just when it was getting interesting.
So apart from the in-flight power, the relight, the targeting, the vertical landing, and the water landings, what's the difference?
Ok, busted, didn't read the article -didn't wish to see it fail. Saw the short vid of it and it did came very close to being successful.