A Southwest Airlines Boeing 737 MAX 8 completed 44 flights with undetected storm damage before a frightening midair problem exposed what maintenance crews had missed. Now, a newly released federal investigation reveals that an earlier inspection contained a warning sign hiding in plain sight.

According to the National Transportation Safety Board’s investigation , hangar surveillance footage showed the aircraft’s rudder moving right but not left during a maintenance test. The test was nevertheless recorded as passed. That missed warning became a central finding in the November 5 report.

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The Warning That Maintenance Crews Missed

The trouble began when thunderstorms struck New Orleans on May 16, 2024, producing wind gusts reaching 84 mph while the aircraft was parked.

Photo by Getty Images

Investigators determined the winds likely damaged…