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SpaceX's Falcon 9 Crashes Into Droneship (cbsnews.com)
SpaceX failed to successfully land its Falcon 9 on a drone ship at sea on Wednesday. Prior to today's crash, the company was able to conduct three successful experimental landing of its used rocket in a row. SpaceX founder Elon Musk noted that the booster rocket had a RUD (rapid unscheduled disassembly, he explained) on droneship. From a CBS News report: It was the California rocket company's fifth unsuccessful drone-ship landing after three straight successes, one in April and two in May. Including a successful landing at the Cape Canaveral Air Force Station last December, SpaceX's recovery record now stands at four successes in nine attempts. But the landing attempt was a strictly secondary objective. The mission's primary goal, the launch of two powerful all-electric communications satellites, was a complete success and regardless of the loss of the first stage, company engineers expected to collect valuable data as they continue their push to make such landings routine.
I like that....
This is still lots better than what NASA is doing. Stressing the technology. Doing new things.
Going ka boom. Everybody needs an earth shattering kaboom now and again. I just wish they'd have audio on the drone ship.
Faster! Faster! Faster would be better!
...the launch of two powerful all-electric communications satellites
I'm glad we are finally getting past the era of internal combustion and the earlier coal-fired satellites!
The KSP community has been using the term RUDE (Rapid Unplanned Disassembly Event). Also lithobreaking is used as a term for crashing.
Musk tweeted:
"Looks like thrust was low on 1 of 3 landing engines. High g landings v sensitive to all engines operating at max."
"Upgrades underway to enable rocket to compensate for a thrust shortfall on one of the three landing engines. Probably get there end of year."
Landing video froze at the last moment but it looked like a bulls-eye landing. There was flame climbing up the side of the stage. Telemetry should be helpful in making improvements.
More important than a successful landing is a successful second takeoff of the recovered Falcon 9 stage. Without that this is just scrap metal recovery.
So we will need to wait and see.
Mr. Musk "get's it". His engineering team is working on the edge of what can be done and failures are going to happen (they're landing a frigging rocket on a ship... backwards). He can either say "we failed" or he can say we had an "RUD". It means the same thing and everyone knows it but it deflects from the technical team somewhat and is gentle signal to the team that their heads aren't on the block (at least yet). It's a good way to lead. Just hope he never uses the world "fail"... because he does have that whole evil genius vibe going.
Some posts are hard to read. For everything else, there's too many links.
NASA's funding depends on pleasing politicians. So they need to be overly cautious and avoid pushing tech till it breaks, even if we would learn more that way.
I think that philosophy is just timidity at its worst. NASA could go and push the envelope and blow some stuff up. They've done it before. The problem is that they lack an administrator with the cojones to stand in front of congress and explain why blowing up the occasional rocket is a good thing.
SpaceX's investors have a longer attention span than voters.
Voters don't have much say in the funding of NASA. In fact very few of them really give much of a shit about NASA at all and NASA hasn't given them much of a reason to give a shit. SpaceX has a CEO who is also a substantial shareholder (reportedly at least 25%) and controls the company which has a LOT to do with the laser focus and long term outlook.
I don't know why, but I can provide some guesses:
1. any contact with a loop, or possibly just aerodynamic effects, risks messing up the engines/thruster control calculations and/or knocking the rocket over
2. loop clearance is going to have to be small if it is going to help (eg. if landing leg fails) but large to avoid (1) - maybe there is no right size
3. need to add in the effects of wave motion on loop and whatever structure is holding it up - for a start, the higher up it is the more it will move, relative to descent path, with the waves
4. a strong enough loop suspension structure may add significant weight to the barge, but more importantly moves it's CofG upwards, making it less stable and giving more roll in the waves, quite possibly negating any benefit from the loop (in terms of chance success)
But I think the big one is this: the rocket _looks_ hugely unstable on landing, and the little legs don't look wide enough, but this is deceptive. With most of the fuel gone and a lot of weight in the engines I bet the CofG of the rocket is probably much much lower than it intuitively looks. Think a long cardboard tube with a lead weight at the bottom - how much do you actually need to stabilise it to get it to stand up?
Now, wind might be a problem, but then it's at sea, if you have high winds you have big waves and you are stuffed anyway.
Last point: they only need to re-use some of the rockets to make launches a _lot_ cheaper, and they don't have much storage space left that they could have put this one in anyway :-)
I imagine adding a ~60m tall gantry with support arm, sturdy enough to withstand repeated rocket detonations at point-blank range (because accidents will still happen), would be a little expensive on what's currently basically a big floating target to shoot massive bullets at. Plus you then have to avoid it during the landing, and have the support arm get in place, adapting to an uncertain rocket position, within a second or so of touchdown before it's too late to do any good.
Then, assuming you solve those problems, you now have a "safety net" that would be financially foolish to not use every time, essentially killing any further advancement in unaided landing stability. Which is counterproductive to their long-term goal of developing the technology to land people on Mars, were there won't be any "safety nets" available. Because *that* is what Musk has repeatedly said is motivating him - launching payloads into orbit is just an economically viable means to that end.
Besides, even here on Earth, being able to land anywhere flat and solid offers far more long-term options than needing a landing gantry.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
SpaceX is doing many of these things under contract to NASA *using NASA funding*
SpaceX has had six launches in 2016 so far and only one of them had any relationship to NASA as far as I can tell (a supply mission to the ISS). The rest were private launch contracts. NASA is a customer of SpaceX and has helped them a lot but if you look at the launches SpaceX has scheduled, relatively few of them are NASA funded.
Well, it seems to be pretty strong if they can transport it on a truck with just one support at each end.
QUIET, SPACECUCK
The body of the rocket, made of thin aluminium, empty of fuel, will crush like an empty soda can when the catch wires will snap.
They need a system with some long articulated arms ending in huge pillows to catch-it :)
They could ask the Tesla engineers who designed the articulated charging arm.
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I think they need a giant articulated arm ending in a gigantic catcher's mitt.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
RUD = rapid unscheduled disassembly
So, a rocket experiences RUD, while a missile experiences RSD?
Try parking your car up to the hubs in salt water. See how that works.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
Falcon 9 Landen, then exploded. That article is too negative. SpaceX managed to deploy 2 satellite into 2 different orbits, successfully!!!!
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An upper capture loop sounds worthwhile, but I have been puzzled as to why the deck of the droneship is not a mesh grid, and the landing feet don't have semi flexible barbs.
I'm sure I am preaching to the crowd here, but the crash should be considered in light of the following facts:
- SpaceX customers still pay for the entire rocket, there is no discount applied yet
- All other competing rockets do not have this capability and burn up on re-entry
- Every landing attempt provides new and unique data that can be used for continuous improvement
- The primary mission (what they are being paid for) was still accomplished
"Of Course I Still Love You", Falcon 9. But it got kinda painful there at the end.
Nice straw man. Who but an unemployed conservative living off the hard work of liberals would have time to waste on such nonsense.
Here's the real story:
http://www.politicususa.com/2014/06/13/study-finds-14-15-biggest-moocher-states-republican-controlled.html
http://taxfoundation.org/blog/which-states-rely-most-federal-aid-0
I've calculated my velocity with such exquisite precision that I have no idea where I am.
You make very valid points, but there is an issue that I think you are missing. All of what you say is basically true, except the part where you say voters don't have much of a say in NASA funding. they actually do, even if it is indirect. They elect the politicians that control policy, and theoretically this is a good thing. But our democracy is corrupted by special interests, so the voters don't don't always get what they voted for, while special interest groups get often get exactly what they paid for. And the fossil fuel industry definitely got what they paid for in the case of the guy voters in the 21st Congressional district elected to represent them in Congress, Lamarr Smith. Smith is an anti-science, religious nutbar from Texas, a card-carrying climate change denier firmly in the pocket of the fossil fuel industry, who incidentally believes the age of the Earth is "10,000 years or so."
The Republican leadership in Congress put Smith in charge of the House Science, Space, and Technology Committee, which has jurisdiction over programs at NASA, the Department of Energy, the Environmental Protection Agency, the National Science Foundation, the Federal Aviation Administration, and the National Institute of Standards and Technology. This one guy basically controls the $39B US government R&D budget. So, what did the fossil fuel industry's money buy them? Check out this brilliant piece of legislation sponsored by Smith. In a bucket, he is trying to get a law that prevents the EPA from getting data from real scientists, and at the same time, forces the EPA to use "data" from oil and gas industry "experts."
I mentioned all this so that you can understand why it is going to take more than balls and a desire to explore to rescue NASA, and why even if voters did care about science policy (remember I agreed with you when you said they didn't) the damage is already done. NASA is now in Smith's sights because they had the temerity to defy Smith by providing independent confirmation of climate change when Smith accused the EPA of using "secret science" to confuse Congress during hearings on the "myth of climate change" as Smith repeatedly characterizes it. Smith is going to strangle funding to NASA if they don't stick to a fossil fuel industry approved script of research activities (read: stop doing research on climate change and stick to patriotic buck rogers stuff, or else.)
That's a well-known problem, with a playbook of solutions in Departments of Nautical Engineering around the world.
Solution (1) - the semi-submersible route (relatively cheap - go buy a redundant offshore drilling rig. Personally I like Aker-H4s, but there are plenty of designs with different motion characteristics and waterplane areas. Chop the derrick off and restructure the deckspace to give the area you want. Build what craneage you want. When landing time approaches, ballast-down to lower the CoG to what you want.)
Solution (2) - Couple the ascent of your "loop suspension structure" to the lowering of massive objects down into the water to get the CoG you want. the Aker-H4 design, for example, can accommodate 2 or 3 25-tonne dead weight anchors at each corner without any re-working - the structure accommodates mounting space and strength for appropriate winches and chain stowage. There's a wheel-reinvention avoidance strategic consideration here.
You know ... decades of design and use of MODUs (Mobile Offshore Driling Units - drilling rigs to those who don't work on them) have led to (a) recognition of the problem of not being able to reach a part of the deck with a crane, when one of the cranes is out of service for [reason], and (b) various different craneage layouts to provide adequate lift/ slew capabilities to the deck area for the design purposes of the particular unit.
Now, I know this may be heretical to the Slashdotter in the street, but, since these are very thoroughly studied problems, and SpaceX don't seem to be using these fairly obvious solutions, then just possibly SpaceX have thought further on this than the Slashdotter in the street an see a problem which we don't, or they've costed it and decided that it isn't worth the money. I'm not going to judge between those two possibilities.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"