ET-121 Crane incident update

by Chris Bergin

A USA source has elaborated on the incident involving the External Tank that will fly with STS-114 – ET-121 – noting a crane cable accidentally slapped into the side of the brand new tank.

Last Thursday, USA workers moved the ET into place on the Mobile Launch Platform for mating with its two Solid Rocket Boosters – Discovery will be de-mated from her current stack in a few weeks time for mating with ET-121.
The incident occurred prior to the lifting of the ET on one of the Vehicle Assembly Building (VAB) cranes.
“Before the ET sling was hooked up to lift it out of the checkout cell in the VAB, one of the connecting drop links (on the crane) ‘bumped’ into tank foam, in the intertank area, due to a crane move that no one was ready for – i.e. the lanyards that individuals hold to secure movement of ‘loose’ equipment (including sling cables, links etc.) was not manned, crane made move and cable/link moved from it’s hanging position and gently swung/bumped the foam,” said the source.
“Determined not to be an issue but, we’ll see if it elevates. Just a shame to have molested a pristine tank.”
Meanwhile, Shuttle manager Bill Parsons claimed – not for the first time – that Shuttle Discovery had a perfect Tanking Test on Friday, the 12 hour loading of propellant failing to show why two ECO sensors failed on the initial test while liquid hydrogen vent valve over-cycled for the second time.
“We had just a perfect test as far as I’m concerned,” said Parsons – repeating comments he – and fellow manager Wayne Hale – noted on the first test.
That proved to be slightly economical with the information when it was revealed that sensor and value issues would ultimately lead to the Shuttle being rolled-back to the Vehicle Assembly Building.
In around a week, managers will hear back on the report from Final Inspection Team on how the ET performed in respect to ice and frost build-up – a cause of concern for the Debris Verification Review in giving their green light to proceed with a Return to Flight launch in the second half of July.

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