BA Boeing Co

By Doug Cameron 

U.S. regulators on Friday proposed an additional fine on Boeing Co. for its alleged use of defective wing parts on some 737 MAX jets that it maintained were ready for service.

The proposed $5.4 million fine from the Federal Aviation Administration comes on top of a $3.9 million penalty proposed last month for Boeing's alleged use of the same type of parts on 737 New Generation jets, the agency said in a statement.

The fines are the latest blow to Boeing's efforts to recover from the 737 MAX crisis, with the FAA alleging the company failed to oversee suppliers and comply with its own quality assurance system.

The affected slat tracks -- which guide flight-critical parts on an aircraft wing -- were weakened because of production problems, the FAA said. More than 300 jets were affected.

Boeing has 30 days to appeal the FAA's latest proposed fine.

Separately, the FAA also proposed a $3.9 million penalty against Southwest Airlines Co. for miscalculating the weight of checked bags loaded on more than 21,000 flights in 2018.

The agency found, after a yearlong probe, systemic and significant mistakes with employee calculations and luggage-loading practices, resulting in potential discrepancies when pilots compute takeoff weights.

Write to Doug Cameron at doug.cameron@wsj.com

(END) Dow Jones Newswires

January 10, 2020 18:14 ET (23:14 GMT)

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