The U.S. Federal Aviation Administration (FAA) has issued an emergency airworthiness directive relating to potential corrosion problems on parked-up Boeing 737 NG and Classic jets that could lead to catastrophic dual-engine failure if not immediately addressed.
The problems involve approximately 2,000 of the 737 variants which have been parked up as consequence of the devastating effect the COVID-19 pandemic has had on domestic and international air travel. Subsequent to receiving reports of four single-engine shutdowns on parked jets, inspectors discovered corrosion-compromised air check valves, prompting them to issue the emergency directive applicable to any of the jets which had been parked up for seven or more consecutive days.
The FAA has made it clear that if any corrosion is found on further inspections, any affected valves must be immediately replaced prior to flying the jet. According to Reuters news agency, the FAA said the directive is to address corrosion of the engine bleed air fifth-stage check valves for both engines. The agency said that this could result in compressor stalls and dual-engine power loss without the ability to restart.
Boeing announced last Friday that it had recommended operators to inspect all their planes, adding that: “with airplanes being stored or used infrequently due to lower demand during the COVID-19 pandemic, the valve can be more susceptible to corrosion.”
