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Cause of Space Shuttle Damage May Be Resolved
August 5th 2005
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Thermal Protection System repair
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Engineers have been
investigating the possible causes for the “foam shedding” incident
that has led to a temporary grounding of future space shuttle
flights. The fleet is grounded until a solution can be formulated
for preventing future foam detachment.
Reports indicate the foam
dropped away from the location where a small repair was made to a
half-inch dent on Discovery’s enormous external fuel tank. A .9
pound piece of insulating foam became dislodged right at the point
two minutes after lift-off.
Although this piece did not hit
the Space Shuttle, this could solve the mystery behind the images
caught on tape July 26th. Cameras showed the large
dislodged chunk of foam narrowly missing the Space Shuttle.
The repair was made earlier this
year at the Michoud Assembly Facility in New Orleans where
Lockheed-Martin built the tank. According to the New York Times a
standard sanding and blending process was used to repair the small
blemish. “The hard lightweight insulating foam was sanded around
the dent to leave a larger, slightly indented surface.”
This repair and others were easy
to spot after the tank was exposed to the sun and the areas became
discolored. Some larger areas may have required carving away foam
and pouring in replacement foam, thus rebuilding the entire
section. The contractor kept detailed records of all of the
repairs.
It has been speculated that this
type of “repair” could have caused the 2003 Columbia disaster. Ice
builds up on the tanks because 500,000 gallons of liquid hydrogen
and oxygen fuel freezes the condensation on the exterior of the
tanks.
The foam was needed to protect
the super-cooled surfaces from ice buildup. It was feared the ice
would fall off and damage the space shuttle. Now it appears the
foam itself has become the damaging debris. NASA has recently
developed strategies so that large pieces of foam don’t become
dislodged.
NASA has cleared the
Discovery for return to Earth next week after conducting wind
tunnel tests on a thermal “blanket”. They have determined there is
no need to send the astronauts on another space walk to fix this
problem. The astronauts have already fixed damage to two tiles that
became dislodged.
If you have any comments or
corrections please
email me.
By
Dan Wilson
Best Syndication Staff Writer
Space Shuttle Books
Keywords and Misspellings: Discovery NASA
shutle spase fome
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