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Space X Made History- 1st landing of an Orbital 1st stage.

Static test on the recovered stage went well for the most part. They had a problem with an outer engine--and will check it out with a borescope.
 
Trying to land on the barge again, correct? Perhaps they're never going to get that to work very reliably. It looked like a leg buckled although I don't know if that was cause or effect.
 
On Twitter, Musk hypothesized that the fog/condensation present at launch froze inside the locking mechanism of the landing leg on the way down, causing it to tip over after landing. He felt it also would have fallen over in dry land, so the barge wasn't the issue.

I was amazed it stuck the landing as well as it did, on the webcast you could see the barge was pitching considerably in the rough seas.
 
Landing a Rocket on a barge is really difficult to do.I was hoping it would stay upright. The weight of the Rocket and a lot of elements could've caused it to tip over.
 
Reanok said:
Landing a Rocket on a barge is really difficult to do.I was hoping it would stay upright. The weight of the Rocket and a lot of elements could've caused it to tip over.
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As noted, we already know the cause. One of the legs failed to lock.
 
The landing legs are not wide enough to counter the ebb of the ocean that that landing pad is located on. The legs of the rocket need to be at least twice as wide in their landing diameter to counter the top heaviness of the rocket that makes the rocket unbalanced when landing on a platform that has an un even movement to it. If you place a stiff legged person in a boat and the boat is ebbing up and down then the stiff legged person will fall over. But if the person bends their knees while being placed in the same boat the ebb will not cause the person to topple. Basically the landing legs need to counter act the ebb of the platform by remaining stiff on the high side of the ebb while opposite leg is able to move up and down on a slide.
 
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all the weight is at the bottom with the engines. The stage would have to reach 23 degree tilt with the current legs before it would loose balance. The size of the legs are fine. They just need to fix that locking mechanism.
 
Better to have that failure early on..I see a minor tweak of that locking mechanism in the near future.
 
MANT! said:
Better to have that failure early on..I see a minor tweak of that locking mechanism in the near future.
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I was wondering, would the ocean landing help here? On the completely horizontal landing pad it may have stayed upright even with the leg not locked, or am I being naïve again? They should have still noticed it, since these things should have multiple sensors, but there's nothing like an explosion to spot there's an issue. That explosion costed dozens of million dollars, because they could already start reusing those rockets – first gets tested & sent to a museum, obviously, but the second can fly again.

I was somewhat surprised they didn't land all the rockets they knew they could, and risk an ocean landing on those where they couldn't do a land one. It was a sign of confidence the water landing would make it, and the bit that failed was not related to it – so they can do those.
 
MANT! said:
Better to have that failure early on..I see a minor tweak of that locking mechanism in the near future.
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I've understood that they've already fixed the legs on the new version which landed succesfully on the land. And that this January 17 launch was the last launch of the old version in any case.

From here: https://en.wikipedia.org/wiki/Falcon_9_v1.1
Falcon 9 v1.1 made its final flight on 17 January 2016.
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New version is "Falcon 9 v1.1 Full Thrust" which already landed succesfully on land.
https://en.wikipedia.org/wiki/Falcon_9_v1.1#Falcon_9_v1.1_Full_Thrust
Falcon 9 v1.1 Full Thrust completed its maiden flight on 21 December 2015, carrying an Orbcomm 11-satellite payload to orbit and landing the rocket's first stage intact at SpaceX's Landing Zone 1 at Cape Canaveral
...
Design improvements announced later in the year included a larger and stronger interstage with revised stage-separation mechanism; revised grid fin design; and upgraded structures for the landing legs and first stage.
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Basically they used last one of the old lineup on the Jan 17 launch. So it wasnt that surprising that the legs gave in. But better to go out in flames than just drop it in the ocean.
 
Maybe vertically oriented arrestor gear could help:
http://www.defensenews.com/story/de...pult-cvn78-ford-arresting-aag-emals/21119327/

With R-7, you have four petal arms that swing away when the thrust-to-weight ratio reaches unity.

Here, I'm thinking four (American) football goalposts lighter weight that rise quickly--the crossbars made of cables that snag under those flat grid fins, similar to N-1, but on the top of Musk's rocket: http://www.defensenews.com/story/de...pult-cvn78-ford-arresting-aag-emals/21119327/

Like the twin towers of the WTC, Falcon is heavy not only at the base but up top--so if the barge leans just a bit--it may be too much for the legs to handle.

Cables attached to arrestor gear threaded through poles--so the stage can pendulum down--that may be the best bet in chop.
 
As has been noted, it would take a 23 degree lean before the falcon 9 first stage would be in danger of tipping on it's legs. No need for Rube Goldberg devices, they just need to fix that locking mechanism on the leg.
 
What really amazes me (besides the fact that the entire feat is amazing) is the fact that the first stage has so much fuel remaining on board when it lands. I have no idea how much but judging from the size of the explosions after failed landing attempts; it appears to be considerable.
 
It takes a lot less fuel to land something than it does to launch something, especially when landing in an atmosphere.
 
sojourner said:
As has been noted, it would take a 23 degree lean before the falcon 9 first stage would be in danger of tipping on it's legs. No need for Rube Goldberg devices, they just need to fix that locking mechanism on the leg.
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Nothing wrong with complex Heath Robinson devices if they are surface based. The barge is really what is most re-usable. The more the barge can do--the less the rocket has to nail perfectly. Had some arrestor system been used--the landing leg would have been the only problem--and then fixed.

each failed landing was due to different things--and active barge allows for more catches of close calls.

I think you might like this from nasaspaceflight:

2016-01-23-042855-350x281.jpg


the internet community – via a series of humorous videos and photos (one on the left via a NSF member) – were quick to note the difference between Blue Origin’s suborbital success and SpaceX’s much more difficult return of an orbital rocket.

Mr. Musk was also quick to note the difference in a series of tweets.

However, Mr. Bezos did opt to congratulate SpaceX after its recent Jason-3 mission that almost resulted in the first successful ASDS landing for the Falcon 9 first stage.

“Impressive launch,” tweeted Mr. Bezos. “SpaceX will soon make Falcon 9 landings routine – so good for space! Kudos SpaceX!” The comment received thanks from Mr. Musk
 
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