(The Hill) – The Federal Aviation Administration (FAA) is investigating after a Southwest Airlines Boeing 737 Max fell into a “Dutch roll” during a flight last month, The Associated Press reported Thursday.
A “Dutch roll” is a dangerous oscillating motion consisting of a tail slide and roll motion at the same time. It can be difficult to control and recover from, though the pilots of the Southwest flight were able to do so without injuries reported.
The May 25 flight from Phoenix to Oakland, California, landed without incident. The FAA theorized that the roll could have been caused by a damaged backup power unit.
According to a preliminary report by the FAA, an inspection after the plane landed showed damage to a unit that provides backup power to the rudder.
The FAA said other airlines have not reported similar issues.
The investigation comes as Boeing’s 737 Max aircraft has come under close scrutiny this year after a door blew out of an Alaska Airlines flight in January. An investigation found lax safety checks and manufacturing errors in Boeing’s build process, and the company has since faced pressure from regulators and Congress to address the issues.
“There are issues around the safety culture in Boeing. Their priorities have been focused on production and not on safety and quality,” FAA Administrator Michael Whittaker said in March. “And so, what we are really focused on now is shifting that focus from production to safety and quality.”
The FAA earlier in March said its six-week audit of Boeing found “multiple instances when the companies allegedly failed to comply with manufacturing quality control requirements.”