Main Engine Cut Off

The US Government Accountability Office published the report on Wednesday. It concluded, "Given several ongoing technical issues, and the work remaining to test the spacecraft element and complete integration of the telescope and spacecraft, combined with continuing slower-than-planned work at Northrop Grumman, we believe that the rescheduled launch window is likely unachievable."

The report catalogs a number of issues that Northrop Grumman has dealt with during the integration process, particularly the technical challenges and workforce issues needed to meet them. For example, the report cites a worrying problem that cropped up during one of the tests to deploy the telescope's essential sunshield—one of its six membrane tensioning systems experienced a potentially crippling "snag."

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All of this has left the telescope project with just 1.5 months of schedule reserve. In recognition of this urgency, Northrop Grumman has, according to the report, increased its daily work shifts from two to three, and teams are now working 24 hours per day on spacecraft integration.