Alaska Airlines has once again grounded all of its Boeing 737 Max 9 jetliners after federal officials suggested that further maintenance may be necessary to prevent another inflight blowout. This decision comes after a portion of one plane's fuselage blew out at an altitude of three miles above Oregon on Friday night. The depressurized plane, carrying 171 passengers and six crew members, safely returned to Portland International Airport with no serious injuries.

The airline had initially returned 18 of its 65 737 Max 9 aircraft to service on Saturday following inspections that took place less than 24 hours after the incident. However, the Federal Aviation Administration (FAA) issued a notice to Alaska Airlines, indicating that additional work might be required. As a result, all Max 9s have been pulled from service until the details about the necessary maintenance work are confirmed with the FAA. It is important to note that other versions of the 737 are not affected by this grounding.

The FAA had already ordered the grounding of some 737 Max 9s on Saturday to facilitate inspections, a process that typically takes about four hours. Currently, there are approximately 171 737 Max 9s in operation globally, making up around 20% of Alaska Airlines' fleet. As a result of the grounding, the airline had to cancel about a fifth of its Sunday flights, while United Airlines, which also grounded its Max 9s, experienced a cancellation rate of about 10%.

The National Transportation Safety Board (NTSB) is currently investigating the incident that occurred on Friday. NTSB Chair Jennifer Homendy stated that they are still searching for the door that blew out during the flight. The investigation is expected to take several months. Homendy emphasized the fortunate timing of the incident, as the airplane had not yet reached cruising altitude when the blowout occurred.

The last major crash involving a U.S. passenger carrier within the country happened in 2009 when a Colgan Air flight crashed near Buffalo, New York, resulting in the deaths of all 49 people on board and one person on the ground. In 2013, an Asiana Airlines flight crashed at San Francisco International Airport, killing three of the 307 people on board.

Flight 1282, which experienced the blowout, departed from Portland at 5:07 p.m. on Friday for a two-hour flight to Ontario, California. Approximately six minutes after takeoff, the fuselage blew out while the plane was at an altitude of about 16,000 feet. The pilots declared an emergency and requested clearance to descend to 10,000 feet, where there would be sufficient oxygen for the passengers and crew. Videos posted by passengers showed a large hole where the paneled-over exit had been, and passengers wearing masks. The plane landed safely approximately 13 minutes after the blowout, and firefighters treated the injured passengers.

Aviation experts expressed surprise that a piece of the fuselage would detach from a new aircraft. Anthony Brickhouse, a professor of aerospace safety, noted that incidents of fuselage panels coming off planes have occurred before, but he couldn't recall one where passengers were able to see the city lights. He emphasized the importance of passengers staying buckled in during flights, as the outcome could have been much worse if someone had been seated in the window seat without their seat belt on.

The Boeing 737 Max is the newest version of the 737, a popular twin-engine, single-aisle plane used for domestic flights in the United States. It entered service in May 2017. The Max series faced a worldwide grounding for nearly two years following two crashes in 2018 and 2019 that claimed the lives of 346 people. The crashes were linked to an automated flight control system, which Boeing subsequently modified before the planes were allowed to return to service. The Max has also faced other issues, such as concerns about overheating and loose bolts in the rudder-control system.

The president of the Association of Flight Attendants, Sara Nelson, commended the crew of the affected Alaska Airlines flight for their efforts in ensuring the safety of the passengers. The investigation into the blowout is ongoing, and authorities are urging anyone who finds the door that blew out to contact local law enforcement.