FAA mandates inspections for nearly 2,000 Boeing 737 aircraft

The Federal Aviation Administration (FAA) has issued a mandatory directive for inspections of the horizontal stabilizer mechanisms on 1,987 Boeing 737 Next Generation aircraft registered in the United States. The measure follows reports from multiple operators regarding unwanted nose oscillations during flight.

The issue stems from excessive mechanical play in the components that allow the horizontal stabilizer to pivot and adjust. If left unaddressed, the FAA warns this could lead to flutter—dangerous aeroelastic vibrations that may result in a loss of aircraft control. The directive specifically covers certain 737-600, -700, -700C, -800, -900, and -900ER models, though the 737 MAX is not included in this mandate.

Air carriers are required to measure clearances in the left and right stabilizer pivot bearings and the adjustment screw mechanism. Depending on the findings, operators must perform additional measurements, repairs, or replace worn parts in accordance with Boeing technical bulletins. While some airlines, such as Canadian North and United Airlines, requested more flexible timelines or extended intervals for inspections, the FAA has denied these requests.