The FAA is investigating a software issue on some Boeing 737 Max jets that could cause problems during aborted landings

The Federal Aviation Administration is investigating a software problem in some Boeing 737 Max this could prompt an automated flight guidance system to disengage during an aborted landing, commonly known as a go-around.

In rare circumstances where there is a missed approach – and where a pilot uses a precision approach with the autopilot engaged and makes changes to his pre-programmed flight plan – a problem with the flight management computer could cause the aircraft’s vertical navigation system, known as VNAV, to disengage and transition to a less sophisticated level of automated pitch control.

VNAV is essentially designed to automatically maintain pre-planned altitude at different waypoints along a flight path.

However, if this problem occurs, pilots will need to take additional measures during their subsequent approach.

The scenario would typically occur in an environment adjacent to a low-altitude airport, where pilots already have a high workload.

“How busy do you want your team to be?” an airline source informed CBS News of the problem. “Are you introducing distractions at the worst possible time?

“Last month, we notified 737 operators of a software issue preventing pilots from having access to automated flight guidance during a specific landing scenario,” a Boeing spokesperson told CBS News in a statement. “We have shared information with operators who have strengthened existing pilot procedures to safely handle such cases. Our engineers are working on a software update to resolve the issue permanently.”

The Boeing spokesperson said that even if the VNAV disengages, the autopilot will continue to operate, adding that all pilots are trained to land safely without a VNAV.

In a bulletin sent to airlines late last month, Boeing told operators the problem did not constitute an immediate safety concern. It appeared in versions 14 and 14.1 of the Max’s flight management computer operating system.

“The FAA is aware of a potential issue in a software update to flight computers on certain Boeing 737 MAX aircraft and is working closely with Boeing and the airlines,” the FAA told CBS News in a statement. “The FAA will convene a Corrective Action Review Board (CARB) and take immediate action if it identifies a safety issue.”

Southwest Airlines and United Airlines informed Boeing that they would not accept delivery of new planes with this operating system, opting instead for an earlier version.

Alaska Airlines, American Airlines, Southwest and United told CBS News that none of their in-service 737 Max fleets use the software version in question.

CBS News has learned that Boeing was first informed of the problem by an airline in November 2024. The company looked into it and determined in February 2025 that it was not a safety issue.

However, Boeing received what a source described as “additional information from operators” earlier this year, prompting the manufacturer to launch a formal safety review board. The committee’s findings were sent to the FAA this month and will be reviewed by CARB.

Boeing’s initial bulletin told airlines that a software fix would be ready sometime in 2028 and that it would issue updated guidance on procedures for pilots to follow in November. The company is working to accelerate both efforts.

The FAA review could further delay certification of the 737 Max 10, the fourth and largest variant of the Max. The Max 10 was thought to be days away from achieving FAA certification, but years behind schedule. The problem could also delay deliveries of the recently certified 737 Max 7. Almost the entire order book for this aircraft is destined for the southwest.

The Max is a cash cow for Boeing and is essential to its turnaround efforts. The aircraft was subject to two high-profile accidents in 2018 and 2019, which killed 346 people due to faulty software and experienced a mid-flight door panel explosion on an Alaska Airlines flight in January 2024, this was blamed on manufacturing errors.

Of note, several U.S. airlines appear to be taking a trust-but-verify approach to Boeing on this issue, after being stung by groundings and delays due to previous Boeing errors on the Max.

The Max 7 was certified with software version 14, while the Max 10 used version 14.1 during its certification testing.

Southwest was expected to begin receiving Max 7 deliveries this fall. It is not yet known whether the airline will take delivery, although Alaska Airlines is expected to be the launch customer for the Max 10.

The software issue was first reported by the Wall Street Journal.

CBS News has also contacted Allegiant Air for comment, which also operates the 737 Max.