The FAA is closely monitoring targeted inspections of Boeing 737 MAX airplanes to look for a possible loose bolt in the rudder control system.

Under consultation with the FAA, Boeing has issued a Multi-Operator Message (MOM), urging operators of newer single-aisle airplanes to inspect specific tie rods that control rudder movement for possible loose hardware.

The FAA will remain in contact with Boeing and the airlines while the inspections are underway. The agency is asking the airlines to work through their approved Safety Management Systems to identify whether any loose hardware has been detected previously and to provide the agency with details on how quickly these two-hour inspections can be completed.

The FAA will consider additional action based on any further discovery of loose or missing hardware. Boeing recommended the inspections after an international operator discovered a bolt with a missing nut while performing routine maintenance on a mechanism in the rudder-control linkage. The company discovered an additional undelivered aircraft with a nut that was not properly tightened.