Software bug holds up Boeing 737 MAX certification

US air safety regulators are delaying certification of the Boeing 737 MAX 10 until they can determine that a new software glitch does not pose a safety risk. The issue stems from a cockpit software update that can cause an automated navigation feature to fail during landings. Boeing shares fell sharply after a Wall Street Journal article detailed the problem.

While the planes already certified by the FAA are deemed safe, the FAA will delay the certification of the 737 MAX 10 until they are satisfied there is no issue. FAA Administrator Bryan Bedford said the MAX planes currently certified are safe, but they will delay the 10 until they are confident there is no problem. Boeing, which relies on MAX production growth for its turnaround, has acknowledged the software issue.

The company has issued a software update to address the problem, which is akin to an iPhone or Microsoft product update. However, Boeing introduced a new, smaller bug in the process. The FAA is working closely with Boeing and airlines, and has convened an advisory board to take immediate action if a safety concern is identified.

Airlines such as United, Southwest, and Alaska Airlines have not flown planes with the problematic software. Boeing's CEO had expected FAA certification of the 737 MAX 10 "very soon."