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SpaceX Grasshopper and re-usable plans

jfull

By jfull
in Science & Spaceflight

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J.Random

J.Random

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Simplest solution would be to buy or lease a nice, wide swath of land on the other side of Atlantic. First stage would do its job, decouple, let atmosphere slow it down considerably, and then perform a powered landing. Then it could be loaded onto a cargo freighter and delivered back home.

Sooooo... they should buy Portugal.

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sojourner

sojourner

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I disagree. They are trying lots of stuff that hasn't been tried before. There is lots of innovation going on in that company. The idea is that some ideas might fail, others might stick technically and economically. SpaceX is about as bleeding edge as it gets...

The difference is that SpaceX is trying lots of innovative things using tried and true technology. How bleeding edge is an RP-1 engine? A space capsule? A 2 stage rocket? Their not trying to develop some SSTO using never before seen engines/tanks/thermal protection with impossible mass fractions.

As to other points, yes, the "rule of fifths" makes sense to the satellite operators, but you can't apply it the the launch operators for the reasons I previously listed.

There actually isn't anything in NASA's contract that says SpaceX has to provide new hardware for each mission currently. Now NASA is SpaceX's biggest customer, so are they ready to take a chance on using refurbished hardware yet? no. But it will most likely happen before the current cargo contract ends.

I think you'll be surprised by how little manpower reusing a first stage will take once things become operational. No doubt it will take hours/days to inspect/turn around, but it won't take the literal army of people that STS required.

Assuming things go incredibly well and landing attempts go without a hitch from day one, when will we see the first re-use? I would guess at least the first 4 to 6 landed stages will end up back at the factory for complete tear down/engineering analysis with maybe the last 2 of those going to McGregor and fired on the test stand then on to Spaceport America for test flights ala GH-2.

Oh, and Elon wants legs on the next CRS mission launching on March 1st. He wants to land that stage back at the cape. If the FAA gives him the go ahead.

If you guys really want to read some good info on SpaceX (and anything space related) I highly recommend this forum:

http://forum.nasaspaceflight.com/index.php?board=45.0

The posters there are predominantly in the industry and have some great insights.

Edited by sojourner
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magnemoe

magnemoe

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Space x plans are not that innovative. Most are based on Russian studies, wish are actually very conservative having been formulated in the wake of many US development failures.

true, no radically new technology. Powered automatic landing was done with moon probes 50 years ago. Using rcs to turn first stage and do an second burn has been done on upper stages 50 years ago.

have it hit the pad with reasonable accuracy has been done with various smart weapons in 20-30 years.

Yes its some challenges you are landing an high stage not an wide probe, you have to turn an huge stage and restart and burn the large first stage engines with enough accuracy to hit pad and do an soft landing, but looking as previous attempt of re use its an simple and cost effective way who can be expanded.

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H2O.

H2O.

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As to other points, yes, the "rule of fifths" makes sense to the satellite operators, but you can't apply it the the launch operators for the reasons I previously listed.

Indeed but the rule of fifths is the one that drive demand. The whole problem is there: even a fully expendable rocket can become very cost-effective if you launch it 50 times a year. But there is simply not that many satellites to put in orbit. So even if SpaceX works perfectly, there won't be 50 launch per year.

So the prices may decrease a little bit (due to launch-cost) but not so much that having a satellite become affordable for more compagnies.

Therefore there will be no more demand, therefore the cost per kg will stay high.

You always read things like "private compagnies always work better than public organisations" but nobody is ever showing evidences of this. It is liberal ideology.

The problem faced by nationnal agencies is basically the same than the problem private compagnies will face : there is not that much things to put in orbit for space travel to become cheap.

For now, at least...

Edited by H2O.
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Psycix

Psycix

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Although no piece of the puzzle is truly new, they ARE the first one to actually try and build that puzzle.

Actually doing it, landing a 10 story aluminum fuel tank on rocket power, is an impressive thing that nobody has attempted before. (And certainly not with 21st century tech)

The parts of the project may not be new, but the entire thing combined certainly is an ambitious and innovative concept.

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sojourner

sojourner

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Indeed but the rule of fifths is the one that drive demand. The whole problem is there: even a fully expendable rocket can become very cost-effective if you launch it 50 times a year. But there is simply not that many satellites to put in orbit. So even if SpaceX works perfectly, there won't be 50 launch per year.

So the prices may decrease a little bit (due to launch-cost) but not so much that having a satellite become affordable for more compagnies.

Therefore there will be no more demand, therefore the cost per kg will stay high.

You always read things like "private compagnies always work better than public organisations" but nobody is ever showing evidences of this. It is liberal ideology.

The problem faced by nationnal agencies are basically the same than the problem private compagnies will face : there is not that much things to put in orbit for space travel to become cheap.

For now, at least...

Some fair points. The thing is, while it may not expand the market much or soon, SpaceX's lower prices will certainly let them grab more market share, forcing other companies to become more price competitive.

It could also cause a paradigm shift in satellite operations. Right now, a company has to schedule months/years in advance for a launch and pay 10's of millions for the opportunity, so naturally, they invest huge amounts of time and money on each payload to maximize that investment. Now, what if they could schedule a launch a mere month in advance for as little as $5 million? (a figure Musk once mentioned as a goal) How does that impact satellite development cycles and cost?

It's too early to tell how things are going to work out, but damn it's some of the most interesting stuff the industry has seen in a while.

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Superluminaut

Superluminaut

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Although no piece of the puzzle is truly new, they ARE the first one to actually try and build that puzzle.

Actually doing it, landing a 10 story aluminum fuel tank on rocket power, is an impressive thing that nobody has attempted before. (And certainly not with 21st century tech)

The parts of the project may not be new, but the entire thing combined certainly is an ambitious and innovative concept.

What about the delta clipper?

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Themohawkninja

Themohawkninja

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I made basically the same thread a while back (and it didn't get stickied :( ). The consensus was, was that it would take a parachute that would weigh so much, that it wouldn't make the system practical anymore.

http://forum.kerbalspaceprogram.com/threads/39752-How-cost-effective-will-the-Grasshopper-really-be/

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fireflower

fireflower

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The Shuttle is a good illustration.
The refurb costs were so high NASA didn't save any money reusing the SRB's and main engines. SpaceX isn't landing its first stage in salt water for that reason, and the Merlin engines are not as high-performance so as to cut down on refurbishment costs.
Add to the fact that the commercial launch market isn't expanding at a huge rate.
It doesn't need to if SpaceX takes contracts away from existing carriers. Arianespace is already feeling the heat. That said, there is an air of the post hoc in your economic factoid. It is possible - and does happen from time to time - that a technological achievement can change the market itself. I can imagine a cynic expressing disdain for the concept of steam locomotives because "the carriage market isn't expanding."
technical achievements, no matter how impressive they are from an engineering standpoint, don't always become an industrial success.
Not all technical achievements are created equal. This is not a flash-in-the-pan technology. The SpaceX businessplan is to reduce costs to orbit by a factor of 10. That does involve technical achievement, but it's primarily an economic achievement, and one that opens the market for space access to a great many other businesses.

Consider the input–output model of quantitative economics. SpaceX is not, according to this model, in the aerospace industry. SpaceX is in the transportation industry, and transportation is the one underlying industry that joins all the others together. At the moment the only customers for this type of transportation are governments and communications companies. Reduce the cost of access to space enough and you have literally every other industry on the planet using your services. Tourism and extraction are just the beginning.

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rpayne88

rpayne88

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No, it would need to burn way more fuel to cross the Atlantic than to go back to KSC. A better bet would be a launch from Texas and a landing in Florida, but even then it would need an extra boost or else it would land in the middle of the Gulf of Mexico. On a conventional launch, the first stage only splashes down 2 or 300 km east of the launch site.

What about landing it on a reinforced, oil rig- like structure? They could then load it onto a modified freighter and service the stage as it sails back to KSC. I'm not a boat guy, but that stage should be back at KSC within twelve hours (assuming a 23kt speed.) If Space X is planing to make them rapidly reusable, this will kill two birds with one stone.

Maybe they could bypass the rig altogether if they could either find a way to stabilize a ship or make the rocket respond to the ship's pitch and roll.

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sojourner

sojourner

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What about landing it on a reinforced, oil rig- like structure? They could then load it onto a modified freighter and service the stage as it sails back to KSC. I'm not a boat guy, but that stage should be back at KSC within twelve hours (assuming a 23kt speed.) If Space X is planing to make them rapidly reusable, this will kill two birds with one stone.

Maybe they could bypass the rig altogether if they could either find a way to stabilize a ship or make the rocket respond to the ship's pitch and roll.

Why do all this when they can just return to launch site? All of that infrastructure adds cost and complexity. They've already done the math and decided that RTLS works from a fuel cost stand point.

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Woopert

Woopert

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Well, I just learned something new today :P

I always that was just part of the design to look cool. Maybe one of the rules in real life rocketry is never do something just cause it looks cool... lol :)

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Psycix

Psycix

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What about the delta clipper?

VTOL with a specialized vehicle is one of the pieces of the puzzle.

Doing it with a full size Falcon 9 v1.1 first stage using first-stage engines is a different piece of pie. :)

Very excited about the new Grasshopper pics! I hope spaceX releases a video soon.

Is it grasshopper v2 or v.1.1?

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