dtb said:

>2. The key is using a vehicle often; the Shuttle WOULD be
>cheap if it flew more.
>
>-- The point is that the SHuttle CAN'T fly much more. The
>reason the Shuttle is expensive isn't that we don't fly it
>weekly, the reason the Shuttle is expensive is that it turns
>out to need months worth of maintenance before each flight.
>This isn't surprising; a Concorde needed a heck of a lot more >man-hours of preparation for each flight than does a 747.
>Since tolerances are tighter and redundancy lower than
>on a 747, because higher margins of performance are
>eeked out of the design, that makes sense. Just like
>an F-22 needs much higher maintenance than a 747.

The Space Shuttle is a flawed design. The engineers who created the Shuttle knew it was a flawed design as they conceived it. The Shuttle's design was forced upon them by political constraints. The Space Shuttle could easily have been made more robust with faster turn around time (at greater development cost). For example, get rid of the delicate silica and carbon-carbon thermal protection system and replace it with a robust titanium thermal protection scheme. The space shuttle main engines (SSME) are high performance and very squirrely (lots of plumbing and moving parts). Get rid of it and go with a big dumb rocket motor like the F-1. There's a performance hit but a big motor like the F-1 could be re-engineered for cheap and easy maintenance. Get rid of the external tank and dodgy solid rocket motors. Instead use a biamese Two Stage to Orbit (TSTO) design based on one of Maxime Faget's concepts. It's not that hard to come up with a robust reusable Space Shuttle design that has low operating costs. The gotcha is convincing the political system to pay for the development costs. I might add in passing that the political system did pay for the development (as military aircraft) for the Boeing 707, 747, 737, Douglas DC-10 and other successful commercial aircraft. One of the reasons that Boeing has been stuck with the 747 for so long is because they can't afford the development costs for a newer design, e.g. blended wing designs, sonic cruiser, etc.

Gary