SpaceX Will SpaceX Successfully Land a Rocket on a Boat?

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SpaceX is attempting to land a rocket on a boat, with a success probability estimated at 50%. Viewers are eager to watch the event live, though concerns arise about the logistics of retrieving the rocket if the landing is successful. Discussions highlight the challenges faced during previous attempts, including issues with hydraulic fluid and descent velocity, which affected landing accuracy. Despite setbacks, the community remains optimistic about future attempts, noting that failures often lead to valuable lessons. Overall, the endeavor reflects SpaceX's innovative approach to reducing costs associated with rocket stages.
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So SpaceX is going to try to land a rocketship on a boat... That's pretty amazing, if you ask me. Does anyone know of a TV station that will be broadcasting the event live? I know I could watch it here http://www.spacex.com/webcast/ , but it would be nice to be able to see it on the big screen with the whole fam
 
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Geez ... that IS amazing. Very surprising that they are even going to try it and even more surprising that they put the odds of success at 50% (at best). Still, they know its capabilities a lot better than we do and wouldn't be trying it if there were not at least some reasonably chance of success.

Seems that landing leads to another problem though ... say it works. THEN what ? How do they get it back onto land?
 
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phinds said:
Seems that landing leads to another problem though ... say it works. THEN what ? How do they get it back onto land?

Ooh I hadn't thought of that. That whole process might actually be as exciting as the landing (if the landing is actually a success of course). That would be horrible if the landing was successful and they damage the rocket when they are trying to bring it back onto land
 
Actually it seems they have accounted for that by recognizing this is a process and that there are bound to be failures along the way, but that also we often learn more from failures than successes. People can say whatever they want to about Elon Musk but I like his cool blend of dreamer and practical "hands on". He sees Problem - Booster stages are where much of the money goes and we throw it away because it is difficult to not throw it away Solution - Find out just how difficult that really is and see what that reveals for a 2nd step and narrow down. The payoff is quite literally astronomical.
 
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enorbet said:
we often learn more from failures than successes.

Thanks! That makes me the cleverest man in the world...
Garth
 
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Despite the crash ( or RUD, if you prefer :P ) it appears a simple problem to repair. As anyone could see there was a problem with attitude as it was at nearly a 45 degree angle rather than perpendicular. Apparently a simple hydraulic system or it's controls failed to do it's job at fin guidance. Redundancy caused the engines to attempt to compensate but it was too little, too late. It is praiseworthy that they hit the barge on target. I doubt it will take much to fix this last wrinkle. Overall as experiments go, quite successful as it lends credibility to the idea that it is by no means an insurmountable problem even with present technology.

Here's the link -> http://www.popularmechanics.com/how-to/blog/spacex-falcon-9-reusable-rocket-failed-landing
 
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Yeah, and from what I understand they're going to make another landing attempt on the 29th, it seems like the chances of success on this one are wayyyy higher than they were before.

I might have misread that though and I don't remember where... Can anyone verify that they are in fact going to attempt another landing on the 29th? I know that they do have a launch scheduled for that day...
 
enorbet said:
it appears a simple problem to repair.
Musk identified the problem as a 10% shortage of hydraulic fluid. If this was a simply problem to fix, then why wasn't it identified earlier, i.e. add an ample margin of fluid, unless the vehicle mass margin is too tight allow such? If that's the case, then adding more fluid won't be simple.
 
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They probably thought they did have an ample margin, and more control effort was required than expected. They'll probably just add more for the next flight.
 
  • #11
cjl said:
They probably thought they did have an ample margin, and more control effort was required than expected.

I could see that being the case if the control profile left expectations; that is, PID control degenerated into some kind of bang-bang oscillation. If that's the case, then fluid store is not the fundamental problem.
 
  • #12
It's also possible if their plant or dynamic models were a bit off. It doesn't require a dramatic oscillation to eat into aerospace-style margins.
 
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13 mins 35 34 33 ...
 
  • #16
And liftoff!

The first stage separated, the second stage is firing, they will try to land the first stage again in a few minutes.

Edit: Second stage engine cutoff and separation.
Dragon has unfolded its solar arrays.
 
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  • #17
Ack, they stopped the live feed and said to check social media for the live landing site action. Facebook is not showing me an obvious live feed. Anybody got a link to a live landing site feed?
 
  • #20
Arg. Wind responsible for "excess" velocity? A 10 m/s wind places more than a half ton of force on that cylinder (~3.7mx30m), meaning it might have to come in with a tilt into the wind. I don't recall any indication of wind velocity on those multiple ground landing tests in Texas.

Barge drift with current/wind? Though barge station keeping is routine.
 
  • #21
The vehicle appears to have incurred a ~20deg tilt from vertical with a single vehicle height remaning above the platform. Last moment positioning correction, or wind forcing? I see white caps on the water so there was at least 10 m/s wind on the surface, higher a couple hundred meters up. I can't see how they avoid some maneuvering thrusters (couple hundred N) at the top of the lander if wind is the problem, as gimballing the engine has against the rotational moment of that lander must be too slow? Only minimal thruster fuel required, in the last few hundred meters before landing. I suppose the mass of the thrusters (minimum two?) would be no trivial matter when every kilo of payload means 98 kilos of rocket.

Descent velocity also seems a bit faster than the Texas tests. Looks like ~30 m/s at 30 m if the video is real time. Descent velocity did zero (apparently) by the time it hit the pad, but that velocity at 30 m also means almost no time to correct lateral velocity - which Musk noted was high. Lateral velocity correction means a vehicle rotation with this scheme, which per above is not quick.

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  • #24
Space X has exploded a few minutes after launch.

Watching the press conference, I gleaned the following:- They have a serious problem. They have 4 months of supplies left on ISS. The crew will be returned when they are down to 45 days.

- Water and water filtration and provisions are probably the biggest loss to the ISS. And the docking adapter and radio system. Russian Progress and Soyuz flights are pending, as is one from Japan later in the summer.

- The ISS water processor is reaching its limits.

- All three commercial vehicles to ISS (Orbital, Progress and Space-X ) were lost in a one year time frame.

- Stand-down of Musk's rocket until problems are understood.

- FAA will have oversight of the investigation which will be conducted by Space-X, which operates on an FAA license.

- Commercial crewed vehicles are paused and under scrutiny, as are budgets. But they want to continue with the concept. Boeing is working on one.

- The Russian Progress launch which adds crew to the ISS is still on for next month.
 
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  • #25
Dotini said:
Space X has exploded a few minutes after launch.
Damn !
 
  • #26
phinds said:
Damn !
No kidding.

I was watching very carefully on a 27" HD screen. At about 2:19, the 2nd stage appeared to ignite while the 1st stage was still thrusting. I could be wrong about that, but the ensuing explosion filled my screen, and the sky filled with smoke and debris. Musk identified a 2nd stage oxygen tank overpressure, but not as the root cause.
 
  • #27
SpaceX had such a good track record :(. The first stage landing looked like a problematic part, but I didn't expect that.

One failure out of 19 launches is still the average ratio, but it will certainly delay several things significantly (including the idea of manned launches).
 
  • #28
mfb said:
SpaceX had such a good track record :(. The first stage landing looked like a problematic part, but I didn't expect that.

One failure out of 19 launches is still the average ratio, but it will certainly delay several things significantly (including the idea of manned launches).

It's 2015.

There are 3 humans in LEO on the ISS. Another rocket failure.

A much needed reality check as people talk about a successful Mars mission by 2040. Our technology is nowhere near any such time line for a trip to Mars. We can barely service 3 astronauts in LEO.

The Shuttle was touted as the most advanced machine ever made. Buzz Aldrin criticized it for exactly that reason. The ISS, the Shuttle, the JWST...victims of technologies that have frenzied and eaten up resources far beyond what they were designed for.
 
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  • #29
Dotini said:
... the 2nd stage appeared to ignite while the 1st stage was still thrusting.
It looked like that to me as well, but it could be just 'appearance of'.
If that actually happened, it's hard to believe. That is that something as simple as an incorrect timing of scheduled events could explain it.
 
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  • #30
tom aaron said:
A much needed reality check as people talk about a successful Mars mission by 2040.
You can stop progress completely with reality checks that are pessimistic enough.
2040 is 25 years away. 25 years before Apollo 11, the first unmanned V2 rockets reached space (but not orbits).
tom aaron said:
We can barely service 3 astronauts in LEO.
3 to 6. We can, but sometimes we might have to send more rockets than planned because no technology is 100% reliable.
 
  • #31
mfb said:
You can stop progress completely with reality checks that are pessimistic enough.
2040 is 25 years away. 25 years before Apollo 11, the first unmanned V2 rockets reached space (but not orbits).
3 to 6. We can, but sometimes we might have to send more rockets than planned because no technology is 100% reliable.

Man on Mars maybe by 2075 or so.

Apollo is peanuts next to a Mars mission. Also, there is not a technological infrastructure ready to take on such a mission. There are not warehouses full of engineers and other warehouses full of piles of money all ready to start churning away if the President and Congress gave the green light.

We are at stage zero. No launch vehicles, no spacecraft , no habitation, no anything. Stage zero. We are grasping at straws trying to just find a reliable means of servicing an orbiting ISS.
 
  • #32
Tom,

The whole Mars landing thing has been totally beaten to a pulp on this forum. Try a forum search. I think the consensus agrees w/ you. I certainly do. There are a few Pollyannas who still think it may happen in the next couple of decades but I'd like to have some of what they're smoking.
 
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  • #33
tom aaron said:
Apollo is peanuts next to a Mars mission.
So is a suborbital rocket compared to Apollo.
No anything is the situation of 1944. Now we have things. We launched missions to Mars - we even set up a communication infrastructure there for the rovers. We launched humans into space. We assembled things in orbit. We had humans living in space for more than a year at a time.
Mars is heavier and much farther away than the Moon, sure. But we have much more than the Apollo program had in 1944. It would need a strong political will, for sure. Not necessarily from the US.

I'm not saying it will happen, but I cannot rule it out. In the same way you probably would have claimed in 1944 that a manned mission to moon within 25 years is completely impossible.
 
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  • #34
mfb said:
So is a suborbital rocket compared to Apollo.
No anything is the situation of 1944. Now we have things. We launched missions to Mars - we even set up a communication infrastructure there for the rovers. We launched humans into space. We assembled things in orbit. We had humans living in space for more than a year at a time.
Mars is heavier and much further away than the Moon, sure. But we have much more than the Apollo program had in 1944. It would need a strong political will, for sure. Not necessarily from the US.

I'm not saying it will happen, but I cannot rule it out. In the same way you probably would have claimed in 1944 that a manned mission to moon within 25 years is completely impossible.

I don't know why anyone in 1944 would have said a manned mission to the Moon was impossible. It was within the engineering capabilities of known rocketry at the time. Engineering is not magic but rational application of technology.

Rovers are machines. Not organic human beings. There is no technology to send a man to Mars, get him there in a healthy state, sustain him for a stay and then return him to Earth. There are not teams of researchers available to do the basic science, develop the necessary technologies. We can barely recirculate water in the ISS for a few months without resupply...there is no room for error on a Mars mission. You don't need one water processing back up system but 5...and they all need to be tested in Martian conditions. Multiple pre human landers would be necessary, redundancies...pre mission non manned flights. None of which we have a scrap of technology to do.

In the 1960's there was an infrastructure of 'dirty hand' engineers who emerged from WW2. This is why the advances in nuclear energy and delivery systems was even more phenomenal than the Space missions. This type of infrastructure does not exist today. There are thousands of pieces of a puzzle that need to be developed and brought together...by who?

The JWST is minuscule in technological needs compared to a manned mission to Mars. It's a decade behind schedule and multiple times over budget. Multiply this a hundred times for what is needed to sustain a manned mission with zero room for error.
 
  • #35
tom aaron said:
... We are grasping at straws trying to just find a reliable means of servicing an orbiting ISS.

That assertion doesn't really survive a reality check given the ISS has continuously occupied for the last 14 years. One might as well resurrect "man was not meant to fly" come the next canceled plane flight.
 
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  • #36
It seems to me that the number one reason that the odds may be higher that we don't put a man on Mars by 2040 or even 2075 for that matter is public will to fund the research needed. Whenever I see words like "eaten up resources" especially when applied to the exploration of space, I can't help it, I bristle. If we look at any graphic of government spending it should be obvious the odds are those funds wouldn't have been "eaten up" in any better endeavor, but more likely to go to another useless tank or bomber that will rust away without ever having been used or to be shuffled off the board into some Classified area so no records need be kept

... and the public as a whole applauds this and uses the Moon Landings not as a positive high water mark, a thing of pride that incidentally had many offshoots and benefits into wildly varied fields but as some embarrassing reductio ad absurdum lever usually in the form of "If we can put a man on the moon, why can't we (insert mundane goal here) and whatever did happen to Tang?" :P

I suppose it is impossible to extrapolate but I'm betting the odds are we wouldn't even be having this discussion as we are, lacking the technology, had not the moon landing been undertaken. I also can't help but wonder what the world would look like if say Wilbur had been very convincing in arguing that glorified kites were eating up the proceeds from the bicycle shop.

I'm glad that private enterprise is now somewhat involved but I'm frustrated and angry that we dropped the ball after Apollo 17 because to me it reveals a misguided set of priorities and a lack of education and understanding of the value of research and exploration.

On a positive note I sincerely hope SpaceX recovers quickly and continues to strive for lofty goals. I really dislike being pushed into sounding like Alan Rickman doing Marvin from Hitchhiker's Guide to the Universe.
 
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