On Friday, technicians at NASA's Kennedy Space Center will conduct a new tanking test at Launch Pad 39 to continue troubleshooting two issues that arose during the tanking test on April 14.
Image: Oxygen vapors stream from the Gaseous Oxygen Vent Hood positioned above Space Shuttle Discovery during the April 14 tanking test. Image credit: NASA/KSC.
Engineers will evaluate the liquid hydrogen sensors in the tank that gave intermittent readings during last month’s test. These sensors serve as fuel gauges to notify the Space Shuttle Main Engines to shut down when propellants reach a certain level in the tank. This is critical in the safe operation of the main engines.
In addition, they will also evaluate a liquid hydrogen pressurization relief valve that cycled more times during the first tanking test than is standard. This valve opens and closes to ensure the liquid hydrogen stays at the correct temperature.
When the tanking test is completed, preparations for rolling Space Shuttle Discovery back to the Vehicle Assembly Building (VAB) will begin.
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