Discovery Wraps up Second Tanking Test

Technicians at NASA's Kennedy Space Center conducted a new tanking test on Friday, May 20, at Launch Pad 39-B to continue troubleshooting two issues that arose during the tanking test on April 14.

Image: A close up of Discovery and its External Tank at Launch Pad 39-B during the tanking test. Image credit: NASA TV/KSC.

Engineers wanted to evaluate 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.

They also wanted a second look at 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.

Technicians are preparing to roll Discovery to the Vehicle Assembly Building (VAB) on May 24. Discovery will be detached from its ET and lowered into the transfer aisle. On or about June 7, Discovery will be lifted and attached to its new ET and Solid Rocket Boosters. It will roll back out to the launch pad in mid-June.

Source: NASA