Originally posted by orca71
Actually the size of oil reserves is just one small aspect of natural resources because it is finite and has limited value in any one fiscal year.

It is one of the most important natural resources, which is why the US is spending billions in Iraq, don't let anyone try to tell you different reasons. That's the main one. I on top gave oil as only ONE example in which the USSR was well positioned, there are many others. The USSR was quite rich in natural resources, although they weren't/aren't always located in the most climatologically hospital places to extract from.

Didn't they "replace" some tiles in space before the last shutle got to re-enter?

I think that would be the main reason for keeping it at 30K tiles instead of 1 big single piece full hull shield. You can easely take a stock of tiles with you to replace some if necesary. You can't however take a spare 1 piece heatshield with you nor replace something of that size with just 2 or 3 guys floating in space.

Other thing, If a non mechanical heatshield were to be developed, how much you recon it would lighten the space shuttle?

I've been wondering about this for a while now. It would seem that an electronic based shield would be much more lightweight then the ceramic tiling heatshield (actualy, the shield itself would weigh nothing at all), untill you think about what kind of powersource the shuttle would need to equip to power the shield.

I recon it would at least need a nuclear reactor on board to power an electronic shield and we all know that the coolant, core, shielding and other parts of a reactor aren't all that light either.

Would a reactor or other electrical powersource (say massive battery banks or something) be lighter then the ceramic heat shield?

Originally posted by Simon666

Originally posted by orca71
Actually the size of oil reserves is just one small aspect of natural resources because it is finite and has limited value in any one fiscal year.

It is one of the most important natural resources, which is why the US is spending billions in Iraq, don't let anyone try to tell you different reasons. That's the main one. I on top gave oil as only ONE example in which the USSR was well positioned, there are many others. The USSR was quite rich in natural resources, although they weren't/aren't always located in the most climatologically hospital places to extract from.

Compared to us their natural resources were pretty meagre. They had roughly the same population to support and were also trying to match our military capabilities which, when you have much less resources, is pretty hard to do. USSR was like Canada with 10 times the population and 100 times the geopolitical and military ambition. It was simple a case of expecting too much from too little for too long.