Science and Society

why dont they just cover the shuttle with one BIG tile? problem solved... i'll send nasa the bill.

If it were one big tile and it were to be damaged, they'd have to replace the entire belly of the ship.

The trouble with one big monster tile could potentially be the increased stiffensss and the resulting inflexibility. The "skin" of the shuttle goes thru enormous temperature swings, vibration, and acoustic loading which cause stress and strain. If the tiles have seams, then there is a place to absorb the stress and strain. Otherwise one big tile would need to have the ability to flex and twist and absorb all of the stress while also being strong and manuverable to assemble. Some of those requirements are conflicting. In addition, in order to make something to cover the area of the shuttle belly, it's thickness would increase and the weight would likely add too much to the lauch weight. I believe that a rough estimate of the cost of shipping something into space is $1M/lb. Not that NASA doesn't have the resources and connections to design the worlds most technologically advanced materials, but sometimes many small pieces are easier to deal with than one big piece.

Actually, the only time they have a problem with items falling off and damaging the tiles, etc., is at liftoff. If they could either stop that from happening (they've had 20 years to figure something out), or else shield the shuttle tiles and wing leading edges until the solids drop off. Then let the shield fall with the SRBs. I shouldn't think that a suitable shield would impose an overly large weight penalty. They certainly can't continue allowing the thing to keep coming apart at liftoff.

Yea I agree, one large tile would solve some problems. And that a shield would do well to protect the shuttle during liftoff. I think a cheaper solution in the long run, would be a replacement for the shuttle. It's quite old as it is, and in need of a more efficient way of transporting people and materials into orbit and furthur. But that takes money.

Yes , the solution to the prolblem is very simple. Private industry can do it by designing a non ablative shield. NASA cannot because it takes too much manaing by too many committes and politicians. Then the cost becomes an issue. Private inndustry will take one year or less to accomplish the job where NASA will take five years and ten times the cost.

Oops! I guess I spoke too soon in my previous posting. Those asbestos composite tiles have been an absolute headache since the beginning of the space shuttle program, where they'd fall off periodically during testing. I'd have thought that the scientists working on the project would have devised some better protection after they'd seen how unreliable those cursed tiles can be.