.3% of cost of the rocket is refueling....Imagine one of these being used a dozen times = major savings.
This and the skylon design are the future.
14th August, 2013 @ 1:51 p.m. (California Time)
Not a very fuel efficient way to land is it? Considering that the shuttle landed completely unpowered and was also a reusable space craft I like that approach better. I wonder how much pollution can be attributed to our exploration and use of space?
15th August, 2013 @ 9:06 a.m. (California Time)
@ Jon Smith: I agree. We must be missing something. What possible value does this method have, other than to imitate 1940s-style scifi rocketry? Can someone enlighten us?
15th August, 2013 @ 9:56 a.m. (California Time)
@ Jon Smith. Maybe this is inefficient. The shuttle might have landed efficiently, but everything else about it was inefficient. It cost $500 million to prep for a re-launch due to all the damage from flight. It was supposed to fly every couple of weeks, instead it flew a couple of times a year. The shuttle was a fantasy to have space craft land like plane because it's cool.
Rockets and capsules is the way humans will be into space for the next few decades still.
15th August, 2013 @ 11:17 a.m. (California Time)
Er...well, I suppose they don't need a runway...but other than that I agree with Messrs. Smith and Menzel. Prima facie It looks a bit daft to take all that fuel all the way up there with all the costs thereof, just so that you can land like Flash Gordon or whoever it was.
Mr. Musk, can you let us in on your thinking?
15th August, 2013 @ 11:31 a.m. (California Time)
re; Jon Smith. habakak
The cost of operating the shuttle is a result of bad design. Starting with the choice of fuel and Rockwell's inability to design adequate robustness into anything.
The vertical landing does work on airless and near airless bodies as well but for earth I want wings.
15th August, 2013 @ 11:48 a.m. (California Time)
@Fritz/Jon: You are comparing apples to oranges. Space travel requires that we build vehicles in two parts, the actual spacecraft (the shuttle) and the lift vehicle (think the Saturn IV rocket or the big orange thing that the shuttle was strapped to during liftoff). Every single spacecraft that has ever reached orbit has used a disposable lift vehicle. They put a spacecract/payload into orbit, and then burn up on re-entry.
The grasshopper is revolutionary because it is a reusable lift system. It will lift a payload into space, and then land back at SpaceX headquarters. Sure, it uses some fuel to land, but the alternative is letting it burn up and building a whole new rocket.
15th August, 2013 @ 12:05 p.m. (California Time)
if you have no atmosphere or just a little this is the only way to land. what we need is a big mussel that goes up and down, if we ever want to leave orbit.
15th August, 2013 @ 1:04 p.m. (California Time)
@ Smith, Menzel, & dalroth5
The space shuttle was an incredibly inefficient design for all the reasons mentioned by @habakak but also since the total fuel required to accelerate the craft + cargo to orbital velocity was enormous. In one of the Space-X articles on the F9R, Elon Musk outlines the differences in economics between the Space Shuttle and the F9R. In lay terms, I think it is most useful to calculate the economics in terms of "useful" or "net" payload to orbit per unit fuel required rather than in terms of gross mass accelerated to orbit. In the case of the F9R, there is only a
15th August, 2013 @ 1:08 p.m. (California Time)
re; Mike W
Landing on thrust is not required for reusability. The booster could land on wings.
15th August, 2013 @ 1:44 p.m. (California Time)
@ Mike W: Thanks for the clarification. Now I realize that the launch rocket will be far lighter without the payload, requiring far less fuel to return. It does seem to make sense now. Thanks.
15th August, 2013 @ 1:58 p.m. (California Time)
"The booster could land on wings."
...at a cost of additional complexity.
You would have either
a) a glider you cannot steer - and get a "brick from orbit" issue people are so happy now finally got rid off with the demise of the shuttle. Shuttle was of so limited use because this was a HUGE issue. You just could not land it at will....you had to respect "landing windows" and tremble if they were not immediately available in emergency. With a glider you are back at this game. Good luck.
b) something you could steer...and then you work with thrusters anyway. Adding wing on lift-off just adds aerodynamic complexity and weight. You would have to lift it up and again. You still have to have thrusters working on the downward trajectory. TWO systems to tame where your resource allowances, on a returning system, are close to null. (I think Elon explains that clearly ..all it takes is listen.)
...oops....yes... of course you can have the parachutes don't you? Yes sure if you want to have to re-process and re-manufacture the whole thing. One more reason why getting rid of the shuttle was such a healthy step.
NO....shuttle was never reusable craft....merely "re-flyable" one.
Grass hopper, after it flies, will be the first really reusable spacecraft EVER.
15th August, 2013 @ 3:40 p.m. (California Time)
I wonder if a system with helicopter-like blades on top that spin it like a Maple seed during descent would ease the fuel budget. Since it doesn't have living passengers the spin might be manageable. The rocket could do the final bit but most of the descent would be essentially un-powered.
Just trying to think laterally. There are more efficient ways of coming down than with rockets. The GPS would have to be able to handle the spin but that's probably a detail.
15th August, 2013 @ 4:15 p.m. (California Time)
Comparing to the shuttle is somewhat apples to oranges. This is more like the shuttle booster rockets which were the other part of that vehicle which was re-used. Of course those huge solid rockets had to be seawater resistant and nearly completely rebuilt. The Spacex system does away with having to carry a complete separate flight system into space, because most of the control apparatus is already part of rocket's take-off systems. rugged landing gear is necessary for both systems but this one doesn't require new tires for every flight. the lack of heavy wings, and the fact that it has only a small percentage of its fuel left( the vast majority of mass of any well built rocket) means it only needs one of the nine engines to bring it back down, while saving the other eight in good condition for reuse.
15th August, 2013 @ 8:19 p.m. (California Time)
Watching that video is like watching a B movie from the fifties, but this is real. That's a bit strange. I guess we've seen a lot things that were just science fiction become science fact in the last few decades.
15th August, 2013 @ 10:44 p.m. (California Time)
The man that said wings are a bad idea also thinks that electric cars and a tube train that would never pay the interest on the loans used to finance the construction of the tube are good ideas.
16th August, 2013 @ 8:04 a.m. (California Time)
Deorbit and land where? 70% of the earths surface is water and a large portion of the rest is unsuitable as well. A glider has a much larger area in which to find a landing strip and does not require an engine to start to not make a crater.
You only need 2 control actuators to get the glider to land and the wings make for high area to mass ratio allowing a cooler reentry.
17th August, 2013 @ 1:35 a.m. (California Time)
There was a very good show on PBS almost decade ago that detailed when Apollo Program was in full swing to determine how to land Astronaut on the Moon and return them back safely to Earth. There were three proposal and one of the proposal was to land the rocket as shown in the SpaceX video (I believe a version of that was proposed by von Braun ) and then there was the winner Lunar Landing Module. I believe the SpaceX type landing was discarded because it was deemed too complex and posed higher risk as well as considerable resources to accompany if there was a problem when along the journey.
For all the money that SpaceX has spent for this test flight they should have outsourced the job to me for justification of this approach :). Oh wait I am not white! This is not science and falls into the category of gimmickry.
17th August, 2013 @ 7 a.m. (California Time)
My question is about the fuel budget. After a liftoff and orbital insertion, how much fuel will be left for a landing? As I recall, for one of the Apollo moon landings, the lunar lander was down to under 10 seconds of fuel by the time the lander touched down. I'm not certain that a rocket booster can carry enough fuel to take off, insert, and land.
17th August, 2013 @ 1:41 p.m. (California Time)
I forgot to mention that for non-cryogenic propellent you can use the wing as tank which reduces the weight penalty.
The fuel supply is not a problem; it is a limiting factor on the payload lift weight and one can imagine somebody paying for the destruction of a booster and striping it of its heat shield as well to orbit a overweight emergency payload. First stage boosters might not need heat shields.
18th August, 2013 @ 1:42 a.m. (California Time)