Posted on 01/17/2016 4:14:01 PM PST by BenLurkin
Elon Musk's SpaceX managed to launch a satellite into orbit Sunday, but suffered another setback in its attempt to retrieve a rocket stage by landing it on a sea-going platform.
SpaceX officials said the Falcon 9 rocket first stage experienced a "hard landing" and broke one of its stabilizer arms designed to hold it upright. The fate of the rocket stage was not immediately known, and there was no video footage of the landing immediately available, those officials said.
This was the third time the Hawthorne-based company failed to accomplish a clean sea landing, although the company brought a Falcon rocket stage back to terra firma at Cape Canaveral, Fla., on Dec. 21 in what many hailed as an engineering feat.
(Excerpt) Read more at latimes.com ...
If they can stabilize the deck on the Z axis they’ll be successful.
If you watch this video you can see how the deck pitches up and down on the barge/landing pad.
https://www.youtube.com/watch?v=0qnmvvueSl4
Land it on land and be done with it. Weather at sea will always be a problem.
They should give up on the barge idea and simply land it on a remote landmass, or better yet, the same pad it launched from through a redesign to increase the first stage glide ratio? There would be a number of advantages to the latter.
Musk tweeted the speed at landing was good. One of the legs didn’t lock.
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However, that was not what prevented it being good. Touchdown speed was ok, but a leg lockout didn’t latch, so it tipped over after landing.
The barge platform could work if they build another platform above it that is able to move up and down with hydraulics to counter the ocean waves.
Like when you move a chicken’s body and her head stays still?
Something like that.
Stabilizer (ship)
https://en.wikipedia.org/wiki/Stabilizer_%28ship%29
As you said, the Z-axis and stability is the killer on landing and afterwards. Landing back at the launch pad would still be the preferred option, IMO. ;-)
The type of motion compensation you suggest requires the vessel to be underway and I don’t think trying to land on a moving target will make things better. A combination of flume tanks and hydraulic motion compensation may work better but the at sea dynamics are really difficult to overcome.
Actually it has the ability to land in motion now, per sey, as it is descending down through a "river of air", and must compensate. Landing on a moving platform, especially one moving with the wind could actually make things easier under certain circumstances.
They should give up on the barge idea and simply land it on a remote landmass,
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Landing on land is easier, but that still would have failed in this case because a landing leg didn’t lock. Barge landings are necessary because not all missions will have enough fuel to return the launchpad.
True, unless the first stage had enough flight surface to make the glide back. Maybe the extendable legs could become fixed fins with perhaps fixed or extendable canards near the top of the first stage body for additional lift and control?
The difference is it would be more expensive. But considering that today’s landing would have been successful if the one leg had locked in place, then the expense would be unnecessary.
More like a gimbaled stove on a sailboat?
So far SpaceEx has chosen to use the crudest of barges to provide their offshore landing platforms. Actually it's not rocket science if they really want to recover the first stage offshore.
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