Model takes the heat
for the space shuttle
Story and photo by Frederick A. Johnsen
NASA Public Affairs
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NASA uses ceramic
models like the space shuttle shown by technician Johnny Ellis to
map skin temperatures on high-speed aerospace craft. Ellis brought
the model to AirVenture from the Langley Research Center in
Virginia. |
Could a surface anomaly
on the space shuttle pose a danger to the vehicle and its crew on
landing? NASA has a way of finding out while the shuttle is in orbit. A
small molded space shuttle model in the NASA exhibit at EAA AirVenture
Oshkosh can be coated with a thermal reactive finish that reveals any
hot spots caused by air friction during re-entry.
When space shuttle
mission STS-121 orbited Earth earlier this month, inspection of the
shuttle in flight revealed a small piece of gap filler material
protruding from its normal position. NASA engineers quickly configured a
small thermographic space shuttle model with a surface irregularity
where the real shuttle had the protruding material. While the shuttle
crew orbited overhead, NASA used the heat-sensitive model to verify the
material would not cause that portion of the shuttle to overheat on
re-entry. This good news meant the crew would not have to spend a
valuable space walk repairing the material, but could concentrate on
other important scheduled duties.
The model flies in a NASA
wind tunnel that can generate temperatures higher than 1,000° F. In
these conditions the special coating, when viewed under ultraviolet
light, reveals rainbow colors calibrated to different temperature
ranges. The model is made from a ceramic material, because unlike metal,
ceramics do not expand under heat. Unlike older thermal test models that
had limited locations for mechanical temperature sensors, the coated
ceramic models reveal temperature variations over their entire surface.
NASA uses heat-predictive wind tunnel
models to forecast the degree of punishment other future aerospace
vehicles can expect to encounter. These and other fascinating aerospace
research and development tools can be viewed in the NASA exhibit’s
craftsman area at AirVenture, staffed by NASA specialists happy to
explain the tools of their trade. A piece of genuine space shuttle
heat-resistant tile is in the NASA AirVenture exhibit. Ask NASA’s
Johnny Ellis, and he might let you hold it.
