After part of the cabin including a window on a Boeing 737-9 Max was torn down, the US aviation authority FAA has ordered a temporary flight ban for more than 170 aircraft of the type.

The authority said immediate inspections of certain aircraft of this model were required, which would take around four to eight hours per aircraft. Only then could the affected aircraft go back into operation. This applies to aircraft operated by US airlines or traveling on American territory – 171 aircraft worldwide.

The incident occurred on a US airline Alaska Airlines flight en route from Portland, Oregon, to Ontario Airport, east of Los Angeles. The airline had already announced that it would initially keep all of its Boeing 737-9 Max aircraft on the ground and subject the 65 aircraft to thorough maintenance and safety checks.

According to media reports, a part of the window suddenly came loose and flew away. There was a big bang and then air rushed in through the hole, passengers told The Oregonian newspaper. The seat directly next to the window was unoccupied, but a teenager in the middle seat suffered injuries from the sudden drop in pressure. There were therefore no reports of serious injuries. The airline said in a statement that shortly after takeoff, the plane returned to the airport with 171 passengers on board and landed there safely.

The hole on the side of the plane was visible in a passenger video published by the BBC. “It wasn’t even the emergency exit. It was just part of the plane,” a woman noted in the video.

Memories of two other emergencies

The incident is likely to alarm airlines and the manufacturer Boeing. The NTSB accident investigation agency is investigating the case. In contrast to the benign outcome on Friday, two emergencies in 2018 and 2019 ended catastrophically and led to the 737 Max series being grounded. There were a total of 346 deaths in the two crashes. The main cause is believed to be a faulty control program that caused the machines to crash to the ground.

Boeing then revised the type and gradually received re-certifications. However, the medium-haul jet continued to make headlines with production defects and put a strain on the manufacturer’s balance sheets.

Alaska Airlines has also increased its fleet in recent years with an improved version of the 737-9 Max. In total, the airline has around 300 aircraft, most of them from Boeing.