|astronautix.com||Anomalies during micrometeoroid shield testing.|
Anomalies that had occurred during micrometeoroid shield testing were summarized.
A series of deployment tests were conducted on the micrometeoroid shield during the course of two years prior to launch. Only one component actually failed during this testing. This failure was the rupture of an ordnance expandable tube which did not affect its intended function of breaking the tension strap, but did allow contaminants in the form of explosive residue to be released.
Redesign was accomplished and no further problems were encountered. Other anomalies that occurred which precluded the tests from being successful were misalignment of deployment latches and failure of latches to engage.
All deployment tests were successful from the standpoint of deploying the micrometeoroid shield to a position which would have been acceptable for orbital operations.
A second micrometeoroid shield component failure occurred during ultimate pressure testing of the dynamic test article. Three of twenty-four hinges that connect the micrometeoroid shield to the straps which run under the main tunnel yielded. The straps were subsequently redesigned to provide greater strength and no further problems were encountered.
The decision to utilize solar panels instead of fuel cells or some form of generator was not made because of economical reasons. Fuel cells had originally been considered; however, due to extension of the mission to 240 days total, and the continued increase in power requirements, the fuel cell concept became inadequate. The solar panels were developed to satisfy the extended mission and high power requirements.