The US regulator FAA recommends inspecting aircraft similar to the

The US regulator FAA recommends inspecting aircraft similar to the 737 MAX

The American Civil Aviation Regulatory Authority (FAA) has recommended that airlines check the doors of their Boeing 737-900ER aircraft after incidents were observed involving the Boeing 737 MAX 9 with a very similar design.

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Companies “are encouraged to conduct visual inspections” to ensure the doors have no defects, the FAA said in a statement Sunday evening.

The Boeing 737-900ER is an older model than the MAX family but shares similarities in door design, according to the FAA.

Contacted by AFP, Boeing had not yet commented.

This announcement follows the incident that occurred on January 5 during an Alaska Airlines flight in which a door separated from the cabin of a Boeing 737 MAX 9 that was scheduled to connect Portland, Oregon to Ontario, California.

Since then, the US Civil Aviation Administration has ordered 171 of the 218 MAX 9s in circulation to remain grounded during an inspection.

The FAA said these devices would only be put back into operation when there were no longer any doubts about their safety.

Boeing suggests that its customers on the MAX 9 lock certain doors if the number of emergency exits is already sufficient in relation to the number of seats in the aircraft.

It was one of those jammed doors that blew off on the Alaska Airlines flight, and the Transportation Safety Agency (NTSB) suspected the problem was with the obstruction wall not being adequately secured.