[meteorite-list] NASA grounds future shuttle flights

[Chris Peterson]

Yes, but the foam insulation on the main tank is sprayed on, and I gather 
that it was the loss of a piece of this foam that is causing the concern, 
not the loss of tiles (although I guess one tile was lost). The shuttle can 
generally survive reentry with some missing tiles; more serious is 
mechanical damage from frozen foam colliding with the structure during 
liftoff.

Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com


----- Original Message ----- 
From: "AL Mitterling" <almitt at kconline.com>
To: "Tom Knudson" <peregrineflier at npgcable.com>
Cc: <meteorite-list at meteoritecentral.com>
Sent: Wednesday, July 27, 2005 7:06 PM
Subject: Re: [meteorite-list] NASA grounds future shuttle flights


> Hi Tom and all,
>
> The tiles aren't sprayed on but manufactured and each has a number and 
> fits at an exact place on the Space Shuttles. The Shuttle is contoured and 
> so each Tile is a bit different from other tiles and why they are 
> carefully numbered and placed. They use an adhesive glue (type) to secure 
> the tiles. Certain tiles can take more atmospheric heat than other tiles. 
> (black more heat, white less heat)
>
> It is not uncommon for tiles to be replaced during flights. A certain 
> amount of damage has always occurred to some degree but not to the extent 
> that doomed the Columbia. Also they use to paint the ET (external tank) 
> white. They saved money (from weight and paint) by eliminating that step 
> but perhaps the paint would work to secure the foam better on the ET.
> The reason for the foam is to insulate the cold fluids that are the 
> propellants for the main engines on the inside of the ET. It also acts to 
> keep the build up of ice (from humidity outside) to a minimum so it 
> doesn't fall off and damage tiles or other sensitive area on the Shuttle.
>
> I think that the news media is making more out of this than needs to be 
> done. However damaged tiles under and around the shuttle that protect it 
> from re-entery is a concern along with thousands of other items that can 
> be catastrophic in the event problems in those areas occur.