Longview Professor Studied Shuttle Tiles

The investigation of what may have caused Saturday's disaster is centered on the shuttle tiles.

A LeTourneau university professor in Longview once worked at NASA, investigating how shuttles react while re-entering the earth's atmosphere.

Dr. Richard Johnson's studies centered around these same tiles NASA is looking at today.

"This has a water-proof coating on that's one of the things we did some work on," says Dr. Johnson as he puts a drop of water onto a shuttle tile.

Dr Richard Johnson worked at NASA studying the tiles placed along the base and wings of each space shuttle.

"On a launch, for example, or rain this would absorb a lot of water without that coating on there which would increase the load and increase the power requirements."

He also demonstrates the heat each tile is designed to withstand upon re-entering the earth's atmosphere.

"You can heat the lower side to say 2000 degrees and the upper side is cool."

Dr. Johnson believes that the theory that debris damaged tiles during lift off is plausible.

"Then on a re-entry that would've been the problem when the severe heat and turbulence hits that you start knocking off or loosening some of those tiles. Exposing the surface underneath which is aluminum aloids, maybe some titanium but that material could certainly melt at those temperatures compromising the structure inside the wing. Most of the time there's no problem but that one time you get a loosened tile or you get some tiles knocked off could be in a very critical area," says Dr. Johnson.

He says now the space program has once again become a national focus.

"People start getting a little complacent again and the shuttles have been going up and down and people aren't paying much attention until last Saturday."

Dr. Johnson believes scientist at NASA will soon begin developing stronger and more durable tiles.

Amy Tatum, reporting.