Tanking Test classed a success

by Chris Bergin

Another milestone was achieved on Wednesday, as Shuttle Discovery “passed” her tanking test with only a few areas of concern.

Issues that arose from the loading of 500,000 lbs of propellant are all understood to be non-conflicting from initial evaluations – when in reference to delaying the launch of STS-114.

The test – which was highlighted around the re-designed External Tank (ET) – was nearly delayed due to storm weather in the area. However, after the weather was deemed to be a ‘non-threat’ in regards to passing over the Kennedy Space Center, the three hour loading process went ahead on time.
Liquid Oxygen and Liquid Hydrogen were pumped into the two tanks inside the ET, with the Rotating Service Structure rolled back from the Shuttle, ET and SRBs in a dress rehearsal for the launch. All United Space Alliance workers withdrew away from launch pad 39B ahead of the tanking.
Once fully loaded, a special team of inspectors were sent to check for frosting and icing on the tank – which would have been bad sign that the new tank (ET-120) had suffered a level of failure when the super-cold propellants started to mass inside the tanks. However, no reports of problems have been noted at the time of publishing.
“We are very pleased with the overall performance of the tank,” says Neil Otte, chief engineer of the external tank project office. While deputy shuttle program manager Wayne Hale – who even singled out Discovery herself for praise – went further, claiming ‘an outstanding day’, although at least two sources involved in the test claimed – while it was a success  – there were ‘a few problems.’
This is by no means the end of tests that surround the loading of propellant, with 33,000 lbs of hypergolic propellants for the OMS/RCS and APU/HPUs – set for the weekend of April 22nd and 23rd. Monomethyl Hadrazine will be loaded into the OMS/RCS tanks, with Nitrogen Tetraoxide in the Oxidizer tanks.
Milestones will be the aplenty over the coming days and weeks, with the Program Design Certification Review set for Tuesday, April 19th. Around this time NASA will be looking further into the issue of debris strikes – including that of ice from the ET shedding off the tank during assent – causing potential hazards to the Orbiter.
One of the largest remaining – and more so critical – elements on what will set the best-target for a launch date will be the plenary meeting of the Stafford-Covey Return To Flight Task Group, which will occur some time after the Design Review, when NASA hopes to close most, if not all, of the eight remaining RTF requirements.
Not long after that meeting, The Flight Readiness Review will take place. This is when NASA will make its determination on a green light for STS-114 – and more so when.
Another key will be the continued processing of Discovery’s sister, Atlantis. She has to be ready to fly – or at least be at the stage of being able to launch within an acceptable timescale – in the event of a rescue mission, named STS-300, a recommendation of the Columbia Accident Investigation Board (CAIB).
Milestone after milestone lie ahead. However, Discovery is passing them, one by one.

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