The potential electrical problem that prompted airlines to retire dozens of 737 MAX jets from service last week is affecting more areas of the plane’s cockpit than previously known, Boeing Co. said. Friday.
The aerospace giant said last week it had ordered 16 MAX operators to inspect their jets for a potential electrical problem identified while assembling an airplane in Seattle. The manufacturing problem, which Boeing now says affects components in a few locations, will need to be addressed in approximately 90 jets in aviation fleets and in many undelivered aircraft.
Airlines were eager to get their MAX jets back up and running as they prepare for a busy summer, but airlines have said they managed largely without the planes by replacing other jets. Still, the newly discovered defect threatens to undermine the efforts of airlines and Boeing to restore passenger confidence in the aircraft. That challenge comes because the aircraft manufacturer is also working to resolve quality issues that have dogged some of its other commercial and military aircraft.
The issue revealed last week involved the electrical ground path for the standby power supply in certain aircraft electronic systems. A change in the way that unit was installed during production in early 2019 could have interrupted that grounding path; in some circumstances, that could affect the operation of the backup power source, Boeing, the Federal Aviation Administration and airlines said last week.
The same manufacturing changes also affected the grounding path of the aircraft’s main instrument panel and the rack containing the standby power unit, Boeing found during its recent reviews. Those areas also need to be inspected and adjusted, Boeing said.