The head of the National Transportation Safety Board criticized aviation regulators for “downplaying the urgency” of a possible rudder malfunction on some Boeing aircraft in an unusually public rebuke.

The head of the National Transportation Safety Board says the Federal Aviation Administration needs to up the urgency on the potential for jammed flight

The National Transportation Safety Board is issuing “urgent safety recommendations” for some Boeing 737s—including the embattled 737 MAX line— warning that critical flight controls could jam.