The FAA has determined that a software defect affecting Boeing 737 Max flight computers does not pose a safety concern, removing a question mark that had hung over the certification timeline of the 737 Max 10.

On 2 October, a Corrective Action Review Board (CARB) — a panel of FAA safety experts convened specifically to evaluate the issue — concluded that the glitch carries no safety risk. "Following a thorough review, a panel of FAA safety experts on Friday determined a software issue in certain Boeing 737 MAX flight computers is not a safety concern," the agency says. The Wall Street Journal first reported the determination.

The finding matters beyond the technical file. FAA administrator Bryan Bedford said on 28 September that the agency was holding back certification of the 737 Max 10 — the largest and still uncertified member of the Max family — until it had evaluated the defect. That delay now has a defined endpoint, though the FAA has not specified a new certification date for the variant, which Boeing has already delivered in spirit to no airline: the type remains in flight test and certification work years after its original schedule slipped following the 2019 grounding of the Max fleet.

What the bug actually does

The defect sits in flight-management software developed by GE Aerospace. An update intended to fix a "known bug" in the aircraft's vertical navigation system "unexpectedly introduced a new bug," Bedford said on 28 September. In some cases, the new defect can produce an "absence of vertical navigation guidance" — meaning the flight crew loses automated vertical path input during certain phases of flight.

The CARB reached its no-safety-risk determination on specific grounds: "pilots retain full control of the aircraft and the indications to the flight crew are clear and unambiguous," the FAA says. In other words, the failure is annunciating, detectable and manually manageable — the failure-condition architecture regulators look for when classifying a defect's severity.

The agency retains an escape hatch. It says it will revisit the matter if new information emerges.

Operator guidance follows

Boeing will issue a bulletin to airlines outlining how pilots can identify and respond to the issue if it occurs in service. The FAA, in turn, plans to publish a Special Airworthiness Information Bulletin (SAIB) alerting US carriers and foreign regulators to Boeing's guidance. An SAIB is an advisory instrument, not an airworthiness directive — consistent with the board's conclusion that no mandatory corrective action is warranted.

For airlines, the practical consequence is procedural rather than operational: crews will absorb new guidance on a failure mode that the regulator has judged tolerable, and the Max fleet continues flying without restriction. For Boeing, the clearance removes a regulatory obstacle from the Max 10's certification path, the last remaining hurdle before the company can begin converting the largest variant's backlog — including orders from carriers planning high-density single-aisle deployment — into deliveries.

The FAA has not said when it intends to resume or conclude Max 10 certification work, and the timing now depends on the remaining items in the type's certification docket rather than on this software question.