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Another Leak Delays Final Discovery Launch
vsolepr writes "Today's scheduled launch was scrubbed because of a gaseous hydrogen leak near the spacecraft's external tank. This is the fourth time in the past week that Discovery's launch was delayed due to various leaks and electrical issues. NASA now is aiming for a launch date no earlier than Nov. 30."
Unless something was not the best idea in the first place, and even worse implementation (did the Shuttle deliver on any of its main points, as advertised?)
60s, 70s...its designers probably raised on scifi with a whole lot of spaceplanes - no doubt influenced by huge airplane advances in the 40s. Which differed quite a lot from those 130 year old depiction of "our" times (/. & links with unicode...), apparently influenced by rapid advances in (sub?)marine technology. We can build them (take a Harrier, remove wings and canopy), but it doesn't make those past dreams a good idea. Not a lot flying boats around nowadays, too.
One that hath name thou can not otter
Point me to a genuine major advance in airframe materials, thermal protection systems, or rocket engine design since the 1970s and maybe this contempt might be better supported by actual evidence.
That's a very valid point, most people don't realize that there never will be any "magic" improvements in rocketry to bring the cost down to the point that we'll all be taking holidays on Mars. It's still a high-energy problem, and new technology doesn't necessarily make the hard problems much easier.
There have been improvements though, they're just not that big or visible. For example, computer-aided design would allow a new rocket to be extensively modeled without expensive testing. Multiple design and testing iterations could be performed without ever stepping into a machine shop. This in turn allows design simplifications, a reduction in part counts, etc...
Computer-aided machining has made enormous improvements since the seventies, in part complexity, cost, precision, and the type of materials that can be used. Old designs would not have assumed the availability of CAM, so they might rely on manual steps, such as welding and riveting. To use parts made automatically by machines, a design optimized for that manufacturing process is required.
There have been significant materials-science advancements, which is why both Boeing and Airbus are now creating aircraft made of composites, which wasn't practical or cost-effective in the 70s. Of course, some of these advancements have made it into the shuttle, for example the Super Leightweight Tank is made of a high-tech aluminium-lithium alloy. That's an easy part to replace, but upgrading the orbiter would be essentially a redesign, so it has remained relatively unchanged.
The real problem with the shuttle is that the fundamental concept is flawed. It assumes that people are needed in orbit -- robots do a better job now, thanks to advancements in digital electronics. In turn, the original design also assumed that it's worth reusing the container for those people. If there are no people, nothing needs to be reused. The engines might be worth bringing back down, but a small ablative heat-shield and a parachute is more than enough for that, there's no need to build a huge heat-shielded structure with wings and avionics! When it costs $thousands per kg of material sent into orbit, anything not directly serving the purpose at hand is just waste. The orbiter weighs 68,585 kg empty, of which only 9,531 kg is the engines! Not counting the structure required to protect the payload, the remaining 50 tons of shuttle structure is just a huge waste of money. That 50 tons could be payload on every launch. Over the 100+ launches that have occurred, that's 5000 tons of satellites or space probes that could have been launched. A large satellite is 5 tons, so that's over a thousand that could have gone up, but didn't. Just imagine: if only 10% of those were for solar system exploration, we could have had a hundred or more additional space probes out there among the planets!
project orion wasnt really a good idea. what you really need is something more like NERVA for the upper stage, or some sort of nuclear reactor powered ion engine. like a scaled up VASIMR for in space travel.