Posted on 10/02/2011 8:06:59 AM PDT by Dagnabitt
PrintZach Rosenberg Washington DC 10:30 29 Sep 2011 Source:
SpaceX has confirmed its intent to build a fully reusable multi-stage launch vehicle.
SpaceX CEO Elon Musk announced on 29 September that SpaceX will officially attempt to build a reusable space launch system. Once the first stage burn is finished, the stage will detach, then relight the engines for a vertical touchdown at the launch pad. The second stage will deliver the payload to its required orbit, then re-enter the atmosphere for a vertical landing.
"It's a very tough engineering problem, and I wasn't sure it could be solved," said Musk. "In the last twelve months or so I've come to the conclusion that it could be solved, and I think SpaceX is going to try to do it. We could fail, I'm not certain of success here, but we're going to try to do it."
It has long been SpaceX's position to build such a vehicle, though the 29 September comments markthe first formal programme announcement. Further of the programme are not immediately available.
Grasshopper, a suborbital vehicle revealed to the public by a mandatory FAA environmental analysis, is likely a technology test bed for the reusable rocket project. Grasshopper will use a Merlin 1-D engine, currently used on the orbital Falcon 9, to propel itself as high as 11,500ft before performing a guided, powered descent back to the launch pad.
Musk has previously described building a fully reusable rocket as "super-damn hard."
"You're got to strengthen the stages, you've got to add a lot of weight, more protection, you've got to do things that add a lot of weight to that vehicle, and still bring a useful payload to orbit."
"If you look at the cost of the Falcon-9 rocket," -- $54m, according to the SpaceX website -- "the cost of the fuel and oxygen and so forth is only about $200,000. So obviously if we can reuse the rocket, say a thousand times, then that would make the capital cost of the rocket launch only about $50,000."
Musk has consistently said that his goal is to send people to colonise Mars, but that technology must first be developed for applications closer to Earth, such as satellite launches. The considerable cost of launching to orbit is a major barrier to routine space operations.
The reusable programme will not impact work being done for NASA, said Musk, which includes resupply of the International Space Station and launching astronauts into orbit. "Think of this as a parallel thing", he said. "It doesn't really affect the ascent phase of the vehicle. We're really trying to have the descent phase not be 'hits the atmosphere and explodes.'"
Can’t say much for the music.
Where is all the fuel to come from?
Guess they’re just going to use more fuel / less payload. Musk claims this works on paper.
Will be interesting to see how it goes with the Grasshopper test vehicle.
Nice concept - but really can we colonize the moon or something like that rather than build tubes that circle the earth.
I least there may be a payout with minerals etc.
Nice concept - but really can we colonize the moon or something like that rather than build tubes that circle the earth.
I least there may be a payout with minerals etc.
a good parafoil is substantially lighter than a bunch of fuel and far less dangerous.
I saw the video too, Musk said the first stage doesn’t need wings to make a controlled re-entry. All the older designs envisioned a winged flyback booster with a crew. But it just doesn’t seem realistic. The first stage booster would have to be so much heavier. And how much heat would it have to take on re-entry? And the fuel necessary to make a controlled return vis a vis the amount necessary to launch the payload?
Musk says it works on paper but I help but think I’m looking at the Sanger antipodal bomber.
Here’s another SpaceX video along the same lines.
http://www.youtube.com/watch?v=6p6EruPdoXY
I read the other report about it, still laughing about the coming down and landing up right. LOL. Love thinking in the bucket.
How did Apollo land on the moon?
Interesting point...
It's a classic problem in system dynamics text books. Including mine which I bought around 1970. :) Doesn't really matter if the thing is going up, or going down. More precision required at landing of course but not in the tilt component. Hardly beyond the state of the art.
As for the fuel, the thing will be a lot lighter coming back, and it only needs to put out as much thrust as it's weight, which is constantly decreasing as it descends. Still whatever fuel it takes has to be lifted with everything else. It's conceivable that might be lighter on average than a winged flyback booster, fuel and all.
When they pull if off let me know.
They already have, at least the low level part. Lots of times, including the lunar lander trainer.. which did have some "issues".
Like a JDAM does it...
I see all that obsession with a vertical landing, from various companies (Space X, Blue Origin, and Armadillo). Is that the holy grail? Just seems so much easier to stuff the damn things with parachutes, and then retrieve the things from the ocean. Refuel/reuse. I admit I have not looked into the whole flight envelopes proposed, so maybe I am just not seeing things correctly...
I’m not sure why the parachutes and ocean landings are not desirable. I suppose having a rocket engine full of seawater isn’t the best thing. Also parachutes and their deployment systems have weight. And I guess there may be more transportation costs too with recovering stuff from the sea and bringing it back to the launch area.
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