Today’s launch was scrubbed. Below is a blow by blow of how things proceeded through the launch window.
• 1:15 PM: T-4 minutes and holding. The launch has been postponed from 1:24 PM EST to 1:45 PM EST.
– Investigating a “fill and drain” valve on the Atlas V which failed earlier during topping off activities but has since return to functioning status.
– Wind levels are in the “red” for launch which is still OK but is prompting further monitoring.
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• 1:27 PM: Still in the final built-in hold. Still go for 1:45 PM EST launch.
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• 1:35 PM: Waiting for final report on upper level winds to release the hold at T-4.
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• 1:39 PM: T-4 minutes and holding. The launch has been postponed from 1:45 PM EST to 2:10 PM EST. Today’s launch window will close at 3:23 PM EST.
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• 2:06 PM: T-4 minutes and holding. A tracking station command transmitter (necessary for launch) in Antigua has gone offline. The launch has been postponed from 2:10 PM EST to 2:30 PM EST pending the station coming back online.
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• 2:26 PM: The Deep Space Network has reported that is unable to support launch operations at this time.
– The launch has been postponed from 2:30 PM EST to 2:50 PM EST pending the issues with the DSN are resolved.
– Antigua reports that it is fully mission capable and green at this time.
• 2:31 PM: T-4 minutes and holding. DSN is back up and ready to support.
I had hopes of getting to see this launch from my house but after teasing me with broken clouds all morning — and through the initial launch times — it has now completely clouded over a solid gray.
• 2:43 PM: T-4 minutes and holding. The launch has been postponed from 2:50 PM EST to 3:05 PM EST. No further information, although I just overheard them uploading the latest weather data to the vehicle guidance system software.
• 2:50 PM: Today’s launch window closes in 34 minutes.
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• 3:00 PM: T-4 minutes and holding. The launch has been postponed from 3:05 PM EST to 3:23 PM EST. NASA wants allow all time possible to understand ground level winds in order to ensure a safe launch.
• 3:15 PM: T-4 minutes and holding. The plan is to release the hold on schedule for launch at 3:23 PM EST while continuing to monitor the wind speeds at the pad. If the wind exceeds 33 knots the launch will be scrubbed for today.
• 3:19 PM: The count has resumed.
• 3:21 PM: NO GO at T-2 minutes 34 seconds for a “red line monitor fault.”
– Winds at the pad are exceeding 33 knots.
– Launch is scrubbed for today.
– The vehicle is currently being “safed” for a 24 hour recycle.
– The clock will be reset to T-4 minutes and holding status.
The launch window for tomorrow opens at 1:16 PM EST closing at 3:15 PM EST.
Images in this post are screen grabs from NASA TV.