FAA reviewing Boeing 737 Max software issue affecting vertical navigation

The FAA is investigating a software update to the flight management computer on some Boeing 737 Max aircraft to determine whether it creates a safety concern for pilots, the agency confirmed.

The agency said the issue can cause the airplane's vertical navigation system to disengage incorrectly and switch to simpler automated guidance during certain landing scenarios. The FAA is working with Boeing and airlines and will convene a Corrective Action Review Board of its own safety experts. The board will decide whether the matter is a safety concern and, if so, how to address it, and will review Boeing's proposed fix. The agency said it will act immediately if a safety concern is identified.

Boeing told operators the issue does not pose a safety concern and that existing pilot procedures cover such cases, according to a company statement. Its engineers are working on a software update to permanently resolve the problem.

Boeing learned of the glitch in 2024 and convened a formal safety review board in September, which shared its findings with the FAA. The matter had not been publicly disclosed. Several customers for the 737 Max 7 and Max 10 variants have said they will not take delivery of aircraft fitted with the software update.

The update is not in use on aircraft flying for Alaska Airlines, American Airlines, Southwest Airlines or United Airlines, according to the account, while the Max 7 and Max 10 each use versions of it.