The Federal Aviation Administration has ordered inspections of hundreds of Boeing 737 Max jets. The airworthiness directive was issued on Thursday.
The directive affects an estimated 471 aircraft. Operators have been asked to undertake checks for cracks in a component, with reports specifically highlighting issues near doorways.
These inspections follow reports of cracks found in parts of some earlier Boeing models. The regulator stated that such cracks could undermine the structural integrity of the aircraft.