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The Federal Aviation Administration has issued airworthiness directives to address potential problems with Boeing Co.'s 787 Dreamliner commercial planes, which are built in North Charleston and Everett, Wash. File/Bloomberg/Matthew Lloyd

The Federal Aviation Administration this week ordered airlines to inspect for potential hydraulic leaks on Boeing Co.'s 787 Dreamliners and mandated new flight-control software and parts for the wide-bodies built in North Charleston and Washington state.

The planemaker says it addressed the problems years ago through recommendations to airlines, design changes and production improvements. The FAA order makes those recommendations and changes mandatory.

An airworthiness directive on Monday requires Dreamliner operators to inspect ailerons and elevators, which can be damaged by lightning strikes and leak hydraulic fluid. Ailerons are strips on the wings that allow an aircraft to bank left or right. Elevators are flaps on the tail that move a plane's nose up or down.

Boeing says it recommended the inspections in a 2017 service bulletin to operators and made design changes to fix the problem.

Reuters reported on Wednesday that the FAA also mandated new flight control software and parts to address potential loss of braking and steering power on the ground. The FAA is requiring the installation of hydraulic tubing, a pressure-operated check valve and new software.

Boeing told Reuters in an email that the issue "has been long since resolved" with system improvements on existing Dreamliners and in the manufacturing process.

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Boeing has come under intense scrutiny in the wake of two fatal 737 Max crashes that killed 346 people and a report in The New York Times alleging shoddy production at the company's North Charleston campus.

A software problem is suspected as the cause of the 737 Max accidents, and the FAA has grounded the planes that are built in Renton, Wash.

Boeing is one of the Charleston region's biggest employers, with about 7,000 workers and contractors at the Dreamliner assembly campus and other facilities in North Charleston.

More than 800 of the aerospace giant's 787s are in fleets around the world, and Boeing has a production backlog of nearly 600 Dreamliners.

Reach David Wren at 843-937-5550 or on Twitter at @David_Wren_