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    The Myth of the ease of space travel.

    Posted by Charles Gray on July 1, 2011

    It isn’t quite ready yet, but one of the chapters of my book is about a very common myth-that we would have better space travel if only NASA and other government groups would get out of our way, that it’s somehow “easy” to get into space, especially if you unleash the invisible hand of capitalism.

    Sorry guys, it ain’t so. The Shuttle for example, looks clunky because it was built in the 1970’s with (in some cases) 1960’s technology and was the result of a number of compromises.  NAsa would have loved a better space truck– hell, before Vietnam destroyed their budget, they were designing them.

    But we still used the shuttle and none of the big companies, not one, built their own designs to take advantage of the invisible hand of capitalism.

    There were two reasons for this:

    1. You really couldn’t make a profit, and

    2.  No Virginia, getting into space is a hell of a lot harder than some advocates would like to think, and getting into space with a reusable LEO vehicle is harder by orders of magnitude.

    Let’s think of what our design would require:

    1.  It has to get into orbit. That can actually be pretty hard.

    2.  It has to do so with a reasonable payload.  The shuttle does this.

    3.  Ideally, it has to be completely reusable.

    Here’s where the hard part starts.  To make something reusable, you have to bring it back down to the ground, right?  Sounds simple, but consider this, that means that every bit has to be designed to come back down, and do so in a functional way. That adds weight to the space craft– weight that then has to be trucked up to space.

    Now, you can argue, as some designs in the 1960’s did, that the way to handle this is to have your space craft (the part that enters space), carried up to orbit piggybacked on a launcher.  The concept looks great, and is often pointed to as an “easy” way to improve the shuttle.

    However, it’s not so easy– for one thing, you than run into questions of just what do you put in the lower body?  Make it slow and you dont’ have to worry about supersonic flight, and especially separating from the shuttle orbiter component at supersonic speeds– remember during these designs we had not suffered the Columbia tragedy, and so it is very likely that such supersonic designs today might be more vulnerable to potential damage of the orbiter components reentry systems.  This isn’t insurmountable, but it’s another factor in a design that would make it far from “easy.”

    4.  It has to be (relatively) easy to maintain. That’s where the space shuttle fell down from the original hopes, but it’s something that is absolutely necessary.  If you want any sort of space commerce, don’t look at the Shuttle, look at the planes at LAX.  That’s the sort of fast turn around you really need.

    But here again, cruel reality bites– the planes at LAX are far, far less durable than any orbiter would have to be.  A Jumbo Jet can survive an engine failing, and land, it can survive a hole openin up in the air frame, or problems with the electronics– they have in the past.

    An orbiter?  Those will result in a total vehicle and crew loss.  An orbiter cannot “let it go” if an engine appears to be having a minor problem.  It cannot fly until it makes money before a full over haul.  Believe me, if it could, NASA would by flying the shuttles more– the slow up in their launch schedules from the first optimistic hopes was forced on NASA, not something they chose.

    But mass commerce depends on reliability.  You can see that with the problems we face whenever a storm or other event closes a number of airports–and people at those airports aren’t say, depending on planes to bring them the oxygen they need to breath.

    So reliable orbiters will either  1. Be very large in numbgers, enough that you can afford to have a non-trivial number of orbiters sidelined for repairs, or 2. Be so well designed that they are as reliable as a jumbo jet and that last borders on magic.

    We’ll leave off this exercise by remembering one thing– the Concorde was a triumph of engineering, yet it never made it’s money back.  Furthermore, it is a pale, pale reflection of what a commercial, reusable orbiter would have to be. It’s also far cheaper.

    That is, for advocates of mass space travel, a very sobering thought.

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