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how many missions can an orbiter window

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withstand

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that's a determination that must be made

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at the end of each flight

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in order to determine the flight

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worthiness of the six thermal orbiter

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windows each one must first be

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laboriously hand cleaned

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a haze makes on to the surfaces in the

10
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the cleaning process takes approximately

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a week of labor

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and only after the haze is removed can

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small scale debris impacts on orbit and

14
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booster separation exhaust result in

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damage to the windows

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a mylar is made for flight to flight

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comparisons

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the new defects are evaluated using an

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epoxy mold impression

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any crater depth exceeding six ten

21
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thousandths of an inch results in a

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window

23
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replacement a new inspection system has

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been developed by the inet special

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instrumentation laboratory at ksc

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a lightweight scanning frame automates

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the side light optical scattering method

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and shows defects in the presence of

29
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this automated optical technique can be

30
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performed prior to polishing the windows

31
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and it provides a permanent and accurate

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a computer image can be printed onto a

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mylar and archived in a database for

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the second phase of the automated

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inspection employs a high resolution

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camera system to determine a maximum

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by adapting technologies already in use

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in shuttle and payloads defect analysis

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at ksc