Two years ago, NASA's Genesis spacecraft gently reentered the atmosphere with its cargo of solar wind particles and then plowed straight into the Utah countryside at about two hundred miles per hour, cracking those cargo containers and making a mess of its samples.
So what happened?
Apparently, its gravity sensors were installed upside down.
...and a centrifuge test that would have caught the problem was canceled from the manufacturing process by the builder, Lockheed-Martin. Notably, this was a design rather than an installation error -- the sensors were drawn in upside down in the specs.
Lockheed-Martin's recent record is a little patchy in terms of simple errors screwing up big space projects:
Similar oversight has led to several previous losses, including the Mars Climate Orbiter, which was lost in 1999 because engineers used navigation measurements in both metric and English and failed to make conversions.
The same year, the Mars Polar Lander, was doomed by a software design error that caused the probe's descent engine to shut down early as it prepared for touchdown.
In a brief statement acknowledging the report, Lockheed Martin, which also built the two failed Mars probes, said, "The Genesis mission serves to again remind us just how demanding space exploration always is and how exact our efforts must be."