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You've got it backwards. It is completely impractical to build an entire spaceship, and then throw it away after every launch. Reusable vehicles are the only way to get launch costs down.

You can boil the transportation cost function down to a single independent variable: flight rate. For low flight rates, the costs per flight are very high, and are dominated by the labor of the engineers who design and build the vehicles. For higher flight rates, the costs drop, and are dominated by the costs of the physical materials used to build the vehicles. And for the highest flight rates, the costs bottom out and are dominated by the cost of fuel. All current modes of transportation (cars, buses, trains, ships, and airliners) have their cost dominated by the fuel cost. Only space travel is the outlier. Why? Because we're throwing every vehicle away after a single use!

Not to mention, any launch vehicle must have a capsule able to withstand re-entry anyway, to handle high-velocity launch aborts, so you might as well use it for an actual reentry later.

And to answer your original question, you could conceivably survive reentry from orbital velocities using a very large ballute:

http://en.wikipedia.org/wiki/Ballute

But it would probably need to be so large as to be impractical.




Take a hard look at the shuttle. Most of it - the weight, the complexity, the cost - comes from trying to bring it back intact. Wings, landing gear, hydraulics, flight control systems, etc., is all there solely to bring it back.

All that extra weight means a much bigger rocket is needed to push it up, it means you've got far, far less payload, and you're still stuck in low earth orbit only.

Weight is so expensive I don't think the economics can ever pan out for reusable rockets.


Most of it comes from a series of awful compromises with the military. The Air Force wanted it that big so they could put up and recover very large classified cargos from various places, iirc in less than one orbit.

Also, if the shuttle had actually been used as much as intended the cost wouldn't have been nearly as much.


You can make a reusable launch vehicle that's economical. You can also make one that is incredibly expensive, if its poorly designed. The two are not mutually exclusive.

Kind of like how most cars are cheap on a per-use basis, but it would be insane to use a formula-1 racecar as your daily driver.

That's basically the shuttle. In fact, it's worse. More like putting that F-1 engine in an 18-wheeler sized truck, only doing 2 trips to the grocery store per year, and having the ferrari racing team's engineers and mechanics rebuild the engine and replace the tires after every trip.


>You can make a reusable launch vehicle that's economical.

I find that difficult to believe, given the enormous extra weight that will be necessary.

Look at the Apollo rocket, with that teeny tiny capsule on top of that massive thing. The capsule was the only thing that came back, and that whole massive rocket was needed to push that little capsule to the moon.

Now add wings, landing gear, etc., to the capsule, and imagine how much bigger the Saturn V would have to be.


Wings aren't the only way. Both Elon Musk (SpaceX) and Jeff Bezos (Blue Origin) are pursuing reusable launch vehicles that land vertically by gimbaling and throttling the rocket engines.

This isn't wishful thinking either -- both have already done some initial low altitude VTVL tests. Videos here:

http://www.engadget.com/2012/09/22/spacexs-grasshopper-verti...

http://www.blueorigin.com/updates/updates-2011-11-17-video-o...




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