Over 2,500 Boeing 737 airplanes must be inspected due to a potential issue with emergency oxygen generators, the US Federal Aviation Administration (FAA) said on Monday.
In case of cabin depressurization, oxygen masks drop from the overhead compartments. After Boeing detected that some of the generators might not work due to a flaw with retention straps, the FAA issued an Airworthiness Directive requiring their immediate inspection.
The order affects some 2,600 Boeing 737 Max and Next Generation models. Airlines have between 120 and 150 days to finish inspections and undertake “corrective actions” if needed, and have been banned from installing potentially defective parts.
On June 17, Boeing sent a memo to airline clients identifying a potential problem with the emergency oxygen supply. Under certain circumstances, the plane maker said, the restraining straps on the generators could shift by up to 1.9 centimeters, preventing them from working properly. The company blamed a faulty adhesive, which was introduced in 2019.
“We have gone back to the original adhesive for all new deliveries to ensure the generators remain firmly in place,” Boeing said in a statement. Inspections of undelivered airplanes have not identified any units that were affected by the flaw, the company added.
While Boeing’s bulletin called for visual inspections, the FAA directive has the force of law. Airlines are required to check every generator and replace any faulty straps. An average 737 has 61 oxygen generators, with two straps each, though configurations may vary per airline.
Monday’s announcement comes less than a day after Boeing was fined $243.6 million for not complying with the terms of its 2021 settlement with the US government. Following a series of fatal crashes of the 737 Max – which resulted in the grounding of the entire fleet in 2019-2020 – Boeing had agreed to pay over $2.5 billion to avoid prosecution for deceiving the FAA about the autopilot flaws.
Boeing is the last remaining maker of large commercial aircraft in the US. Under Sunday’s plea deal, the manufacturer has agreed to invest at least $455 million over the next three years to improve its safety and compliance programs and submit to a three-year probation by a special monitor appointed by the government.