The U.S. Federal Aviation Administration said on Monday that seats on hundreds of Boeing 737 MAX jets registered in the U.S. were incorrectly installed and need to be fixed.
If not, the seats could injure passengers and crew members during an emergency landing or block the aisle and slow an evacuation, the agency said.
The FAA's proposed airworthiness directive issued on Monday would apply to 453 jets registered in the U.S. The agency only has jurisdiction over U.S. airlines, but foreign regulators typically follow FAA directives if applicable.
The FAA said in the airworthiness directive proposal that it received a report that some passenger seat assemblies were not correctly installed in the seat tracks.
That meant the assemblies could disengage from the seat tracks if there was an increased load, turbulence or an emergency landing, the FAA said.
"This condition, if not addressed, could result in injury to passengers and crew during an emergency landing or could block the aisle, which could slow evacuation," it added.
There could be up to 69 track-mounted passenger seat assemblies on each 737 MAX plane and the issue would take an estimated one work hour to fix each assembly and requires no parts to do so, the FAA said.
It did not say how quickly airlines would need to correct the issue.
