Boeing has detected a software flaw in 737 Max aircraft that could, in a specific landing scenario, disable an autopilot navigation feature, prompting the US Federal Aviation Administration to open an investigation. The flaw appeared after a cockpit software update, and the company’s engineers are developing a permanent fix alongside temporary measures to help pilots deal with it.
The landing scenario that disables autopilot navigation
The flaw can appear when a flight crew decides to abort a landing attempt and then changes the planned flight path. In that case, pilots may have to continue flying manually without some autopilot functions, potentially increasing their workload while flying at low altitude, particularly in difficult weather conditions.
Boeing said it notified 737 Max operators of the problem in late August and began working with airlines on a procedure allowing pilots to reactivate the autopilot navigation feature when needed. The company added that it had shared information with operators to strengthen the existing procedures pilots follow to deal safely with such situations.
Boeing said its engineers were working on a software update to resolve the problem permanently, adding that, in its assessment, the flaw did not pose a flight-safety risk. The Federal Aviation Administration, meanwhile, said it was continuing its investigation and would take any necessary action if the assessment showed that this was required.
Southwest and United ask for an earlier version
Southwest Airlines and United Airlines told Boeing they did not want to take delivery of new 737 Max aircraft equipped with the software version under investigation and requested an earlier version, according to aviation industry officials. Boeing also told airlines that they could revert to the previous version of the software.
Investigation could affect certification of Max 7 and Max 10
The investigation could affect plans to bring the 737 Max 7 and Max 10 into service. A senior Federal Aviation Administration official said the agency approved the Max 7 for commercial operation last month using the new software in which the problem appeared.
The official added that the findings of the federal investigation could affect certification of the Max 10 if the agency concluded that the flaw constituted an unsafe condition requiring correction before approval was granted. Southwest has been waiting for years to take delivery of Max 7 aircraft and plans to begin operating them next year.
At the same time, US airlines including Delta, United, American and Alaska have placed orders with Boeing for Max 10 aircraft, linking the model’s certification path to the regulator’s findings on the software.
Boeing review began after November 2024 report
Boeing said it first learned of the problem from a 737 Max operator in November 2024, but said the information available at the time did not meet the company’s criteria for beginning a safety review. After exchanging more information with airlines and receiving additional feedback, Boeing began a formal safety review this month and then briefed the Federal Aviation Administration on its findings.
In a notice sent to 737 Max operators last August, the company said it expected to provide additional guidance by November. The notice also said Boeing expected to release the permanent software fix in early 2028, but the company confirmed that it was seeking to bring forward both the guidance and the final solution.
Temporary operating procedures remain in place for now, alongside the option of using an earlier version of the software. Canadian airline WestJet said it did not consider the flaw a safety issue, explaining that it had standard operating procedures and training to deal with this type of event and limit its effects.
GE Aerospace, which developed the software in question, also said it was working closely with Boeing and would support the Federal Aviation Administration’s assessment. The new flaw is once again putting Boeing’s, US regulators’ and airlines’ systems for handling potential safety problems on the 737 Max to the test.
The model came under intense scrutiny after two crashes in 2018 and 2019 killed 346 people and led to the aircraft being grounded for nearly two years. Both crashes were linked to a flight-control system known as “MCAS”. In response, Boeing introduced modifications and additional safeguards to the aircraft’s control system before the 737 Max returned to service after completing regulatory requirements.
