SpaceX plans ocean platform landing

[Norbert]

That video began earlier and ended later.

At the end, it looked like there was enough fuel left for an attempt at damage control (re-launch away from the ship). The thrusters at the top of the rocket tried to keep it from falling over, but started relative late with that attempt. However, starting earlier would have meant to consider letting the rocket slide sideways, something the software was probably not prepared to do (if that had been better).

In the beginning, there was apparently another attempt to control lateral movement. Perhaps that valve, or whatever malfunction, kept producing different results than the control software was expecting, yet it would also seem that the software probably wasn't prepared for that eventuality. In any case, a problem that is surely correctable, and I think the video proves that eventually this method will be successful.

 

[hockeythug]

Magnificent explosion.

 

[Johan]

New post:

Thnx for the video link!

I watched it like 5 times thinking "it might not tip over this time" Man, that was close. I'm super they'll get it next time. It comes in hot but they've got the "braking" just right - vertical velocity is right at 0 as it hits the barge. A bit to much lateral though I wonder how much velocity it could have sideways and still not fall over? Those legs sure gives it quite a bit more supporting surface area as they fold out.

And did you see that thruster on the top of the rocket on the side it fell towards working hard to try and keep it from tipping? I was rooting for it!

 

[voidptr]

Certainly, for the rockets they've been testing previously, of which they circulated videos, they had plenty of fine control of thrust and could go up, hover at will, then drop in a very controlled way. Are you saying this rocket is quite different from the one they tested previously? That seems strange, if true.

The Grasshopper / F9R-Dev vehicles had some extra mass (fuel and/or weights) on them so one engine could throttle below a TWR of 1.0. The production stages are lighter by the time they get to the landing burn, and the TWR at lowest throttle is well above 1.0.

 

[jeff_adams]

The mad scientist in me wants to see four posts quickly telescope up 2/3 the height of Falcon. Once extended, each post has a snare that slips off the other posts and tightens around the rocket.

Explosive charges that fire off when the rocket hits the barge and "snare" the rocket in an upright position. Sort of a reverse airbag.

 

[Lump]

SpaceX To Land Reusable Launcher on Ground

COLORADO SPRINGS, Colo. — SpaceX hopes that the next attempt to land its Falcon 9 reusable launch vehicle will occur on solid ground.
While not providing details of when or where that attempt would occur, Gwynne Shotwell, SpaceX President and COO, told Defense News on Wednesday that the company hopes its next attempted landing will take place on land, not at sea.

 

[Krugerrand]

And did you see that thruster on the top of the rocket on the side it fell towards working hard to try and keep it from tipping? I was rooting for it!

Just need to add an extra thruster on that side. :biggrin:

 

[MyJoule]

Cross post from the other video thread: "Best thing is they probably got a lot of data that they can use in the simulation/modeling - this will give them the info to perfect this provided the hardware is working. They should be able to figure out if it was algorithm/coding or a real hardware performance problem from the data- They certainly learned a lot more about the dynamics and how the 1st stage responds to it's controls. This is amazing. They came so close. and this is very hard rocket science. Too bad the news media is playing this as a failure- it was a learning experience, and not an unexpected result... I suspect with a lot of modeling/simulation they may nail this on the next try. Great Job SpaceX team."

 

[ZsoZso]

A rather negative commentary from BBC:
SpaceX rocket crashes into barge after failed landing - BBC News

"A SpaceX rocket has crashed into a floating ocean platform, after hitting it too hard following an attempted landing."

They make it sound like a messed up attempt of a routine operation. No mention or hint that landing a first-stage rocket after use has never been achieved before.

 

[doug]

A rather negative commentary from BBC:
SpaceX rocket crashes into barge after failed landing - BBC News

"A SpaceX rocket has crashed into a floating ocean platform, after hitting it too hard following an attempted landing."

They make it sound like a messed up attempt of a routine operation. No mention or hint that landing a first-stage rocket after use has never been achieved before.

I read another article that referred to the crash as a "setback". These people aren't knowledgeable enough to know what progress looks like.

 

[hockeythug]

Next attempt maybe on land?

SpaceX hopes that the next attempt to land its Falcon 9 reusable launch vehicle will occur on solid ground. While not providing details of when or where that attempt would occur, Gwynne Shotwell, SpaceX President and COO, told Defense News on Wednesday that the company hopes its next attempted landing will take place on land, not at sea

http://www.defensenews.com/story/de...ground-attempt-reusable-landing-sea/25827625/

 

[ecarfan]

Quote from the article:
------------
The most recent test of the technology occurred Tuesday, when the rocket appeared to land on target safely before tipping over. The hope is that the added stability of landing on ground would allow a safe landing.
"Just purely the boat moving, even in a low sea state, it's hard to imagine that vehicle is going to stay vertical," Shotwell said. "That vehicle is big and tall, compared to the itty-bity-greater-than-a-football-field-size ship."
--------------
It strikes me as odd that she is saying that publicly now. Surely SpaceX realized that from the start?

And an examination of the video from the drone deck of the latest attempt shows the rocket landed at an angle and with some lateral velocity. It seems like even if that attempt had been made on land it still would have tipped. But of course I could be wrong...

 

[Cosmacelf]

We don't know how much lateral movement the platform had. It is possible it was drifting itself.

 

[green1]

A couple of points, SpaceX did realize it, but it's hard to get permission to land on land if you can't prove a whole lot of accuracy, the 2 "failed" attempts at sea have done that. Secondly, landing exactly the same way on land would result in the same problem, however you can designate a larger area on land and therefore ease up your precision a bit which is less likely to end up in what appears to be a last second over-correction that resulted in the "excess lateral velocity" that was the problem.

Land helps a few things, and they are now at the perfect stage to try it.

 

[hockeythug]

It would have to be somewhere in Florida correct? Assuming they launch from the Cape?

 

[voidptr]

A couple of points, SpaceX did realize it, but it's hard to get permission to land on land if you can't prove a whole lot of accuracy, the 2 "failed" attempts at sea have done that. Secondly, landing exactly the same way on land would result in the same problem, however you can designate a larger area on land and therefore ease up your precision a bit which is less likely to end up in what appears to be a last second over-correction that resulted in the "excess lateral velocity" that was the problem.

Land helps a few things, and they are now at the perfect stage to try it.

I think part of it is with the barge they have to bring the rocket down alongside it and do a last second divert to the side so they don't torch the barge with the bulk of the landing burn. A big concrete pad won't have the same problem with engine blast, nor will it have all the support equipment in close proximity.

 

[Grendal]

Photos: SpaceXs debris-strewn landing barge back in port | Spaceflight Now

Photos of "instructions" with debris.

Next up, landing on land. Hopefully they get the permission they need.

 

[AudubonB]

Re the barge:

So now what they have to do is just read the destruction.

 

[GSP]

It would have to be somewhere in Florida correct? Assuming they launch from the Cape?

It will be at SpaceX's new landing complex at CCAFS. The former SLC-13 if I remember correctly.

GSP

 

[jeff_adams]

Maybe SpaceX avoids having to deal with Blue Origin patent issues by moving so quickly to land?