Regulator proposes checks on 453 US-registered jets over seats that may be incorrectly installed.

The US aviation authority has warned that seats on hundreds of Boeing 737 MAX planes could have been installed incorrectly and may require inspection.

The Federal Aviation Administration (FAA) said on Monday that the issue relates to 453 jets registered in the US and proposed requiring airlines to inspect the seats.

If not installed correctly, the seats could come loose during an emergency landing and “injure passengers and crew members”, the FAA said, adding that they could also “block the aisle and slow an evacuation”.

The proposed order would apply only to US-registered planes because the FAA does not regulate foreign airlines.

Regulators in other countries, however, often follow FAA orders when the issue affects aircraft operating in their markets.

A Boeing spokesperson told the Reuters news agency that the company had issued guidance to operators ‌on the matter in December 2025.

“We support the FAA making that guidance mandatory,” the spokesperson said in an email.

The warning adds to years of scrutiny of Boeing’s safety record.

A cabin panel blew off an Alaska Airlines 737 MAX 9 in January 2024, forcing an emergency landing and prompting the FAA to ground 171 jets.

Investigators later found that the panel was missing four key bolts.

The scrutiny intensified after a spate of other accidents around the world, as well as the death of Boeing whistleblower John Barnett in March 2024 while he was providing evidence for a safety lawsuit against the firm.

In June 2025, the US National Transportation Safety Board said Boeing had failed to provide adequate training, guidance and oversight to prevent the Alaska Airlines incident.

There are nearly 2,300 737 MAX jets operating around the world, including 823 in the US, according to aviation advisory and intelligence firm IBA.