SpaceX rocket stage fails to land on drone ship

Los Angeles Times ^ | 01/17/2016 | Geoffrey Mohan

[Jack Hydrazine]

If they can stabilize the deck on the Z axis they’ll be successful.

[Jack Hydrazine]

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

[spokeshave]

Just capture it with three remote controlled helicopters towing a huge net.

[Captain7seas]

Land it on land and be done with it. Weather at sea will always be a problem.

[amorphous]

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.

[Moonman62]

Musk tweeted the speed at landing was good. One of the legs didn’t lock.

...

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.

[Jack Hydrazine]

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.

[eartrumpet]

Like when you move a chicken’s body and her head stays still?

[Jack Hydrazine]

Something like that.

[amorphous]

Yeah, I thought of that too. Or maybe a platform that simply absorbed much of the shock through springs and shock asorbers. The barge could also be designed with underwater stabilizers. This technology is off the shelf and would work well with the barge in motion. It would have to land with a forward motion but that shouldn't be a big issue. And unlike a fixed wing that lands into the wind on a carrier, the barge could move with the wind to negate wind effects.

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. ;-)

[spokeshave]

Or just scale up one of these...robotic snake connector that seeks out and plugs into the charge socket on a Tesla.

[Cannoneer]

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.

[amorphous]

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.

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.

[Moonman62]

They should give up on the barge idea and simply land it on a remote landmass,

...

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.

[amorphous]

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?

[UCANSEE2]

Why can't they use some of these ?

[Moonman62]

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.

[al baby]

More like a gimbaled stove on a sailboat?

[Cannoneer]

Experience doesn't support this, i.e. 3 failed attempts so far. There is technology to afford a more stable platform but is expensive. It is a matter of mass and money. Semi submersible offshore drill rigs use dynamic positioning and motion compensated drilling decks to provide a more stable platform.

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.