Boeing has identified a software issue on some 737 Max aircraft that could affect certain approach procedures after a go-around. The Federal Aviation Administration is assessing the issue and Boeing's proposed fix, while airlines are reviewing the implications because some newly delivered aircraft already carry the affected software version and delivery plans for other models remain uncertain.
Issue Linked to Flight-Path Changes After a Go-Around
Boeing said the problem may occur when an aircraft does not complete an approach as expected and the crew initiates a go-around before changing the previously programmed flight path. On the subsequent approach, pilots may need to complete additional steps to use certain automated functions.
The company said it has provided operators with information reinforcing existing safety procedures for this situation. Boeing engineers are developing a software update intended to resolve the issue. The company also said pilots are trained to land without relying on automation, and that it is working with airlines on formal procedures for restoring automated vertical navigation after the problem occurs.
The FAA said on September 26 that it was evaluating the issue. If a safety concern is identified, the agency said it would take immediate action and review Boeing's proposed remedy. Public information has not established how many aircraft are affected or when the software update will be completed.
Southwest and United Say They Do Not Use the Version
American Airlines said its fleet does not currently have the new software version linked to the issue. Airlines can revert some 737 Max aircraft to an earlier software version.
Southwest Airlines, which operates an all-Boeing 737 Max fleet, said it was aware of the issue and was communicating with Boeing and the FAA. The airline said none of its aircraft has the U.14 software version, including newly delivered Max 8 jets. United Airlines said it would not accept 737 Max aircraft delivered with the new software.
Those statements concern the Max 8 and Max 9 aircraft currently in service, while the status of the other two members of the 737 Max family remains unclear. In early August, the FAA approved the smallest model in the family, the Max 7, which is equipped with the latest software. It is not clear whether the Max 7 can be delivered or placed into service with an earlier software version.
Boeing Chief Executive Kelly Ortberg told investors earlier this month that he expected the Max 10 to receive FAA certification "soon." Alaska Airlines, a customer for the Max 10, said it was working with Boeing and the FAA while the parties assessed the issue and determined the next steps.
Software Version Adds Uncertainty to Certification and Deliveries
For airlines, the software version can affect whether aircraft are delivered and enter service on schedule. For Boeing, the issue comes as the company seeks FAA approval for the final model in the 737 Max family, the Max 10. The scope of the problem, the repair timeline and the next steps for the Max 7 and Max 10 have not yet been clarified.
The 737 Max program has faced years of delays, while Boeing continues to address safety and manufacturing-quality issues. Two 737 Max 8 crashes in 2018 and 2019 killed 346 people; the flight-control software associated with those accidents was subsequently updated. Aviation data provider Cirium estimates that 2,430 737 Max aircraft are currently in service worldwide.