A new software bug found on 737 Max

Boeing Co. has discovered a new software problem on the grounded 737 Max, but the company said that the flaw won’t set back the goal of returning the plane to service in mid-2020.

The planemaker notified U.S. regulators last month after identifying the issue during flight testing, according to an emailed statement Thursday from Boeing. Because of how the plane’s revised flight-control computers handle data, a light indicating that the so-called stabilizer trim system wasn’t working was turning on when it wasn’t supposed to, the company said.

“We are incorporating a change to the 737 Max software prior to the fleet returning to service to ensure that this indicator light only illuminates as intended,” the company said.

The head of the Federal Aviation Administration, Steve Dickson, said that a certification flight for the grounded jet could occur in the next few weeks — a key regulatory step in allowing the aircraft to start flying passengers again.

Dickson said that the agency is evaluating the latest software issue.

The stabilizer trim warning light “had been staying on for longer than a desired period,” Dickson said, without providing more detail.

One of the people familiar with the trim alert problem confirmed Boeing’s assessment, saying it’s not likely to change the projection of returning the plane to service because the company had built padding into its schedule.