All 174 passengers and six crew are safe after incident shortly after takeoff from Portland forced emergency landing.
The incident took place shortly after takeoff on Friday and the gaping hole caused the cabin to depressurise. Flight data showed the plane climbed to 16,000 feet (4,876 metres) before returning to Portland International Airport.
The airline said Flight 1282 – which was bound for Ontario, California – landed safely with 174 passengers and six crew members.
CEO Ben Minicucci said in a statement that the airline had “decided to take the precautionary step of temporarily grounding our fleet of 65 Boeing 737-9 aircraft”.
Flight 1282 and our next steps with the Boeing MAX-9: https://t.co/LFxJvQYNcA pic.twitter.com/oemRokr1tz
— Alaska Airlines (@AlaskaAir) January 6, 2024
Each jet will be returned to service after full maintenance and safety inspections, which Minicucci said the airline anticipated completing within days.
Alaska Airlines has not provided further information about the possible cause, but the United States National Transportation Safety Board and the Federal Aviation Administration (FAA) have said they would investigate the incident.
Alaska Airlines Flight 1282 returned safely to @flyPDX around 5 p.m. local time on Friday, Jan. 5, after the crew reported a pressurization issue. The aircraft was traveling to @flyONT in California. The FAA and National Transportation Safety Board (NTSB) will investigate.
— The FAA ✈️ (@FAANews) January 6, 2024
The new Boeing 737 Max 9 involved in the incident was delivered in late October to Alaska Airlines and certified in early November, according to FAA data.
US aircraft manufacturer Boeing said it was aware of the emergency landing, working to gather more information and ready to support the investigation.
The Max is the newest version of Boeing’s 737 and went into service in May 2017.
All Boeing 737 Max jets were grounded worldwide for nearly two years after two crashes: the first in Indonesia in October 2018 killed 189 people, and the second plane crashed five months later in Ethiopia, killing 157 people.
The aircraft were cleared to fly again after Boeing overhauled an automated flight-control system that activated erroneously in both crashes.
Boeing is awaiting certification of its smaller 737 Max-7 and larger Max-10 jets.
The FAA has carefully scrutinised the Max for years. In 2021, it said that it was tracking all 737 Max aeroplanes using satellite data.