Engineering and test errors apparently caused a U.S. spy satellite code-named Zuma to crash into the ocean shortly after its January launch, as reported by Andy Pasztor in The Wall Street Journal. He writes that the loss of the satellite, believed to have cost as much as $3.5 billion, was caused by the failure of a payload adapter, according to federal and industry investigators.

He adds that one person familiar with the project said the adapter didn’t successfully decouple the satellite from its second-stage booster. Northrup Grumman reportedly modified the adapter to protect the satellite, which was particularly vulnerable to shock and vibration, and tested it on the ground three times.

SpaceX, which provided a Falcon 9 booster for the mission, contended after the launch that its rocket wasn’t at fault—a contention that defense officials have subsequently backed up, Pasztor reports.

He also cites potential issues with congressional review of classified space programs, noting that Zuma was funded outside of normal channels.

In addition, Northrup Grumman is contending with design and production issues related to the James Webb space telescope, with NASA citing “avoidable errors” by the prime contractor. “Northrop Grumman has revamped production procedures for James Webb and other projects, from stepped-up quality control checks to enhanced training, in an effort to lock in tighter testing requirements and prevent employee burnout,” Pasztor writes. His complete article is behind a paywall here.