The Federal Aviation Administration (FAA) has issued a new airworthiness directive for several models of Boeing’s 737 Next Generation aircraft, concerning the possibility of “widespread fatigue damage” in the aircraft skin.
The affected aircraft models are the 737-600, -700, -700C, -800, -900, and -900ER. The total number of the aircraft covered by the AD is undetermined.
Boeing has not commented on the new airworthiness directive.
The 737 Next Generation is a twin-engine narrow-body aircraft produced from 1997 through 2019, until it was phased out in favor of the 737 MAX. Among the numerous operators of 737 NG aircraft are American Airlines, Southwest Airlines, and United Airlines in the U.S., and many more worldwide.
FAA’s Airworthiness Directives instruct operators of aircraft that already have been certified to operate that a maintenance inspection is required to determine whether a particular structural or systemic issue presents a threat to the aircraft’s safe operation.
Failing to comply with the directive may risk the future airworthiness certification of the aircraft.
The current directive follows a determination that “the skin lap splice at certain stringers is subject to widespread fatigue damage” and would require inspection and in some cases repeat inspections, to determine “buckling, wrinkling, bulging at affected skin lap splices,” and repair at affected locations to the fuselage skin on both sides of the aircraft.
In August 2021 FAA issued an airworthiness directive for the 737 NG, concerning failure in the electronic flow control of the air conditioning packs that vent air into the cargo hold. Earlier, FAA ordered inspections for all 737s, to locate faulty cabin-altitude pressure switches.
