[meteorite-list] Space Shuttle Thermal Protection System (TPS)

From: JoshuaTreeMuseum <joshuatreemuseum_at_meteoritecentral.com>
Date: Tue, 28 Jun 2011 20:41:27 -0400
Message-ID: <B91C1D26AFBF4E5EB4695F5BDB586B32_at_ET>

Hi Robert,

Excellent post, I'm going to have to see about getting a tile for our
museum.


Phil Whitmer



---------------------------


 As a fairly new subscriber to the met-list, and a meteorite(nut) collector.
I would like to inject a few pieces of information about the Space Shuttle
Tiles from my personal experiences with them.

As the "other" Teacher In Space(TIS) candidate from the state of NH I was
"given" a damaged flown Tile by NASA way back in January 1986 while I was
attending the TIS Launch Conference (STS-51-L Challenger) in Florida. The
tile that I received, was a black borosilicate coated high tempertaure tile
(HRSI) that was damaged on an earlier mission of the space shuttle
Discovery. (Each Space Shuttle carries approximately 34,000 separate Thermal
Protection System (TPS) tiles. (Thirty to 100 tiles are replaced on an
orbiter after each mission.)

In order for me to receive this tile from NASA I had to sign a four page
security agreement form which stated more things than I can possibly
remember at this time. Basically it stated that this tile was presented to
me as a representative of the "Space Ambassadors" and the state of NH and I
could not sell it to anyone, nor could I charge anyone to see it. I could
not cut it up and give any pieces of it away nor sell any pieces of it. I
could not give it to any person from a foreign country. If I was to retire
from teaching within five years of receiving this tile I had to return it to
NASA. After five years time had elapsed when I was to retire from teaching
the tile was not my personal property but was to stay with the school
district from which I retired (I hope that It is still there).

We were given these tiles of 98.5% pure silicon dioxide to demonstrate the
amazing thermal protection that they offer to the Space Shuttles. Using a
blowtorch hundereds of times in schools all over NH I have never seen even
the least bit of any fusion crust form on the tile that I had used. I
believe that they are so pure that they never "wear out". However, the
borosilicate coating on the tiles does appears to wear thin after repeated
use and may crack and flake and be the cause of replacing numerous tiles for
each mission. This repeated heating and cooling did cause the tile to
discolor from the very black tile to a grey color after repeated use. This
can also be seen on the underside of any of the space shuttles with the
newer replaced black tiles standing out from the grey tiles that have gone
through numerous launch and re-entry missions. So for those of you who dream
of buying a tile from NASA I would say that your chances are about as good
as buying some of the 842 pounds of lunar rocks and soil samples so
staunchly discussed as of recent.

NASA Has had a program in place for many years where they do furnish tiles
to museums, educational and academic institutions etc. For educational
purposes and if you want to see all its "NASAese" go to any of the
following:
http://www.hq.nasa.gov/oia/nasaonly/itransition/Shuttle_Tiles_Disposition_Plan.pdf
http://www.nasa.gov/audience/foreducators/topnav/materials/listbytype/Shuttle_Tiles_Educator_Guides.html
http://space.about.com/b/2010/12/03/schools-can-order-space-shuttle-tiles-for-educational-use.htm

Since my retirement from full time teaching I now work part-time at the
McAuliffe Shepard Discovery Center in Concord NH where we are also an NASA
Educational Resource Center and have received two HRSI black tiles from NASA
for demonstration purposes. When we use them we do use the recommended
cotton gloves to handle them and are careful not to damage them. I would
close by stating that calling these "tiles" is like calling a piece of
styofoam heavy, for the typical six inch square tile weighs no more than a
few ounces (50-60 g) depending on the thickness of the particular tile. In
Fact I will never forget the day that one very unknowelgable colleagues
when first presented the chance to hold a tile in his hand decided to rap it
with his knuckle and promptly crack the very delicate borosilicate coating
rendering the tile as damaged goods. A very dramatic demonstration of why a
space shuttle is never launched during a rain storm.

So any individual who is questing to get a shuttle tile to add to their
collection of space memoribilia I suggest you do as I have done and buy one
from the Buran Space Shuttle Shop.

Robert A. Veilleux
Planetarium Educator
MCauliffe Shepard Discovery Center
2 Institute Drive
Concord, NH 03301
Received on Tue 28 Jun 2011 08:41:27 PM PDT