The Federal Aviation Administration (FAA) is investigating an incident last month when a Southwest Airlines Boeing 737 Max aircraft entered a “Dutch roll” during a flight, the Associated Press reported Thursday.
A Dutch roll is a dangerous oscillatory motion in which the tail slides and rolls at the same time. It can be difficult to control and recover from, but the Southwest Airlines pilot was able to recover without any reported injuries.
The flight from Phoenix to Oakland, California, on May 25 landed without incident. The FAA speculated that the rollover may have been caused by damage to the backup power unit.
An inspection after the plane landed found damage to a unit that provides backup power to the rudder, according to a preliminary FAA report.
The FAA said no similar issues had been reported by other airlines.
The investigation comes as Boeing’s 737 MAX planes have come under intense scrutiny after a door blew off an Alaska Airlines plane in January. The investigation uncovered safety inspection lapses and manufacturing errors at Boeing’s manufacturing process, and the company is facing pressure from regulators and Congress to address the problems.
“Boeing has a problem with their safety culture. Their priorities are focused on production, not safety and quality,” FAA Administrator Michael Whitaker said in March. “So what we’re really focused on now is shifting that focus from production to safety and quality.”
The FAA announced in early March that a six-week audit of Boeing had “found multiple instances in which the companies allegedly failed to comply with manufacturing quality control requirements.”
