Southwest 737 MAX under FAA crash investigation after Dutch roll near Mach 1

The FAA is investigating a May 25 Southwest Airlines Boeing 737 MAX 8 flight from Phoenix to Oakland, where the plane registered N8825Q experienced a Dutch roll with 175 passengers on board.

At 32,000 feet, the aircraft experienced an out-of-phase oscillation, simultaneous yaw and roll, like a car sliding on ice and unsteadily correcting its course. The flight crew successfully regained control of the aircraft and landed safely on Runway 30 at Oakland International Airport approximately 55 minutes later.

Interior of Southwest Airlines 737 MAX 8

The aircraft's emergency power control unit, which serves as a backup in the event of a main PCU failure and controls the vertical rudder, essential for maintaining directional stability, suffered significant damage. This is classified as an accident.

Flight recorder data indicated extreme G loads ranging from +3.18 to -3.52, with a maximum airspeed of 450 knots. Some suspected that the plane might have briefly exceeded Mach 1.0, although this was not confirmed by investigators.

The plane remained grounded in Oakland for nearly two weeks, before being repositioned at Boeing's facility in Everett, Washington, for further evaluation.

Since this incident occurred on board a 737 MAX, increased scrutiny is being placed given other problems encountered by this type of aircraft.

More View from the wing