Boeing has issued a request to airlines to inspect all of its 737 Max airplanes for a potential loose bolt in the rudder-control system. The request comes after an international airline discovered a bolt with a missing nut during routine maintenance, prompting Boeing to investigate further. The Federal Aviation Administration (FAA) confirmed that it would be closely monitoring the inspections.

The FAA stated that Boeing issued the inspection guidance to airlines after the international operator found the missing nut. In a separate case, Boeing discovered an undelivered aircraft that had a nut that was not properly tightened. Boeing assured that the issue identified on the particular airplane has been resolved, but out of caution, they are recommending all operators to inspect their 737 Max airplanes and report any findings.

Boeing emphasized that there have been no in-flight incidents caused by this condition to date. The company noted that routine checks by flight crews would signal if the rudder was not working properly before an aircraft pushes back from the gate. However, as a precautionary measure, Boeing will be conducting inspections on all airplanes set to be delivered in the future.

Major U.S. carriers, including United Airlines, Southwest Airlines, American Airlines, and Alaska Airlines, have the 737 Max jets in their fleet. All four carriers stated that they do not expect any operational impacts due to the inspections. Southwest Airlines mentioned that they are already performing these inspections during routine overnight maintenance. Alaska Airlines expects to complete the inspection process by the first half of January.

The 737 Max jets have a troubled history. In 2018, Lion Air Flight 610 crashed into the ocean off the coast of Indonesia, killing all 189 passengers and crew members. Less than five months later, Ethiopian Airlines Flight 302 crashed after takeoff from Addis Ababa, resulting in the deaths of all 157 people on board. Following the second crash, regulators worldwide grounded the 737 Max. It was cleared to fly again in late 2020 after Boeing made changes to the plane, including modifications to the flight control system known as M.C.A.S.

Boeing has faced criticism for not informing pilots and airlines about the faulty flight-control system until after the first crash. The FAA has also faced scrutiny for its approval process of the Max jets prior to the accidents. As a result, the FAA has implemented a more-detailed certification process for large planes and required enhanced safety disclosures.

Boeing has delivered over 1,370 737 Max airplanes worldwide since 2017. The company is urging all of these aircraft to be inspected for the possible loose hardware. The FAA will remain in contact with Boeing and impacted airlines throughout the inspection process and may consider additional action based on any further discoveries of loose or missing hardware.