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this is shuttle launch control at

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t-minus three hours and holding space

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shuttle Discovery is poised and ready

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for action this evening as launch

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controllers oversee their data here in

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firing room for at Kennedy Space

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Center's launch control center discovery

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performed flawlessly during its August

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25th launch attempt before showers and

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thundershowers migrated into the launch

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pad 39a Rhea and refused to leave before

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our 136 a.m. launch time and then on our

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next attempt on Tuesday afternoon while

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discoveries external tank was being

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loaded with liquid hydrogen and liquid

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oxygen launch controllers failed to

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receive the proper indication that a

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valve had closed and discoveries aft

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compartment when they commanded it to do

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so when the fill and drain valve which

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is an important part of the main

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propulsion systems liquid hydrogen

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plumbing failed to revert to provide

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that proper signal launch commit

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criteria required that the launch team

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cease filling the tank and begin to

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drain it back subsequent analysis

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indicated that the problem likely was

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not with the valve or its actuator but

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instead with the valve position

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indicator which is a microswitch sensor

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and a test plan was developed to prove

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that analysis Wednesday evening launch

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controllers cycled the valve five times

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and received the proper indications

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every time and noted that the valve

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opened and closed within the required

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time limit and within the time that it

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has on its previous 15 flights the space

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shuttle program mission management team

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met on Thursday and determined that more

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time was needed to develop plans for how

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to resolve the issue in case we received

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the not closed indication when we

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attempted our launch tonight at noon

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today the mission management team again

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convened and ratified the plan that

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would allow us to look at alternative

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readings to ensure the valve closed as

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expected but as it turned out those

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plans were not needed because at around

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four twenty p.m. the vow was closed and

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we received the proper closed indication

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so that whole issue is behind us