The Federal Aviation Administration has launched an investigation into a critical software malfunction affecting Boeing 737 Max jets that could force pilots to take manual control during aborted landings at the worst possible moment—when workload is already dangerously high near the ground.

Critical System Fails During High-Stress Maneuvers

Boeing confirmed last month it discovered a software defect in the flight management computer that causes the vertical navigation system to unexpectedly disengage during missed approaches. The failure occurs specifically when pilots use autopilot with precision approach settings and modify their pre-programmed flight plan during an aborted landing. When the system fails, pilots must suddenly manage additional procedures in low-altitude environments where airports create high-stress conditions and split-second decisions matter most.

The vertical navigation system automatically maintains planned altitudes at waypoints throughout flight paths. When this automation disappears without warning, pilots lose a critical tool during one of aviation’s most demanding phases. An airline source questioned Boeing’s judgment, asking whether the company wants to introduce distractions at the worst possible moment for flight crews already operating under maximum pressure near the ground.

Airlines Reject Flawed Aircraft Deliveries

Southwest Airlines and United Airlines informed Boeing they will refuse delivery of new aircraft containing the defective operating system, choosing instead to accept planes with previous software versions. Alaska Airlines, American Airlines, Southwest, and United confirmed none of their current 737 Max fleets operate the problematic software versions 14 and 14.1. The airline rejections reflect growing distrust after previous Boeing mistakes caused groundings and costly delays across the industry.

Boeing learned about the issue from an airline in November 2024 but initially determined in February 2025 it posed no safety risk. After receiving additional operator reports earlier this year, the manufacturer finally convened a formal safety review board. Boeing sent findings to the FAA this month for review by a Corrective Action Review Board, which will determine whether immediate action is required.

Certification Delays Mount For New Models

The software problem could further postpone certification of the 737 Max 10, the largest Max variant already years behind schedule and previously thought days away from FAA approval. Deliveries of the recently certified 737 Max 7 may also face delays, affecting Southwest’s substantial order book for that model. Boeing initially told airlines a software fix would not arrive until 2028, though the company now claims to be accelerating that timeline while preparing updated pilot procedures for November release.