The shocking Boeing 737 Max 9 incident raises questions about deeper problems | Vox

A door plug falling mid-flight has renewed scrutiny of air travel and of Boeing’s planes.

by Li Zhou

On January 5, the door plug of a commercial Boeing 737 Max 9 came off as the plane was climbing, opening a large hole on the side of the plane, alarming passengers onboard, and raising new questions about flight safety.

The shocking incident — scary on its own — kicked off what has turned out to be a rough 2024 so far for Boeing. Specifically, it drew fresh scrutiny to the Boeing 737 Max planes, which have been involved in two past crashes and have been the subject of prior software glitches. And it has renewed the spotlight on broader quality-control issues Boeing’s planes have had when it comes to manufacturing, storage for parts, and rushed production deadlines. According to an investigation by the Federal Aviation Administration, Boeing failed 33 of 89 product audits that the agency conducted related to the manufacturing of its planes.

The January mishap also sharpened the spotlight on the overall air travel industry, which, while overwhelmingly safe, has been the subject of recent reports about outdated technology that buries important automated warnings, staffing issues leading to air traffic controller shortages, and communication failures contributing to planes nearly colliding. As one of just two major manufacturers of commercial planes, Boeing’s missteps further add to questions about the industry as a whole.

[Related: The Boeing 737 Max 8 crashes and controversy, explained]

The January incident took place about 20 minutes into a flight from Portland, Oregon, to Ontario, California, startling staff and passengers onboard. As depicted in videos and described by witnesses, the door plug suddenly fell away with a loud pop, leaving a hole in the side of the plane. (A plug effectively seals a part of the plane that can be used as a door, closing off the opening if a door hasn’t been installed.) Cellphones, AirPods, a child’s shirt, and a pilot’s headset were reportedly sucked out of the plane due to the change in pressure. Oxygen masks also descended in the plane in order to help people breathe.

Ultimately, pilots were able to conduct an emergency landing back in Portland, and no serious injuries were sustained.

Since the incident, federal authorities — including the FAA and the National Transportation Safety Board (NTSB) — launched investigations and required inspections on 171 Boeing planes. Those inspections have found that bolts and other hardware on multiple planes weren’t tight enough, both United and Alaska Airlines said. The plane involved in the incident, in particular, was missing four bolts, NTSB investigators found, and was due for a maintenance appointment the evening of that flight, according to Alaska Airlines. As of February, the FAA said that 94 percent of the 737 Max 9 planes had been checked and were back in service.

Experts emphasize that such incidents remain rare and that flying overall is still extremely safe compared to other forms of transportation like driving. They note, however, that careful inquiries will be vital to ensure that a concerning mishap like this one doesn’t occur again.

“I wouldn’t be terrified of this. I know it is alarming. But the thing to remember is flying is still very safe,” Dan Bubb, an aviation expert at the University of Nevada Las Vegas, told Vox. “It also underscores a very important thing, which is: Leave your seat belt on at all times.”

Investigators thus far have uncovered important details about the lead-up to the incident, though they’re still seeking information about who specifically worked on this aircraft. Per NTSB investigators, the plane’s pressurization warning light had already been triggered on three earlier flights, and the plane had been barred from flying long distances across bodies of water as a result. Additionally, the four missing bolts on the plane’s door plug were likely key to holding it in place.

A major danger in a scenario like this, in which a hole opens up in the cabin, is people being suctioned out of the plane because of the change in pressure. “Anything that is not cinched down is gonna get sucked out of the plane,” says Bubb. Additionally, planes are pressurized so people can breathe at high altitudes, and the gaping hole created by the accident depressurized the cabin, making it harder for people to do so. The oxygen masks that deployed helped address this issue, he notes.

Because people had their seat belts on and because the plane was at an altitude of 16,000 feet, the impact of the door’s loss was thankfully limited to objects, like a smartphone that was later found in a person’s yard. In past instances, that’s unfortunately not been the case. In a 2018 Southwest Airlines accident, a woman died after being partially sucked out of a window, and in a 1988 Aloha Airlines accident, a flight attendant was killed after the top of a plane was torn off.

NTSB Chair Jennifer Homendy noted that a much worse tragedy was averted due to the timing of the incident. “We are very, very fortunate here that this didn’t end up in something more tragic,” Homendy said in a statement. “No one was seated in 26A and 26B, where that door plug is.” She emphasized, too, that things could have been worse if the flight had reached an altitude that would have allowed people to walk around the cabin. Bubb added that the risks of being sucked into a vacuum would be much higher for someone who wasn’t buckled in.

In addition to wearing seat belts, which can also offer important protections in the case of turbulence, Bubb recommends passengers listen to the routine safety demonstrations that flight staff offer at the start of travel in order to be able to act quickly should an emergency occur.

Recently, there have been several high-profile air travel incidents, like an early January crash in Japan that left five people dead and a 2023 FAA system outage that grounded and delayed domestic flights, both of which have contributed to fresh scrutiny of the industry.

That doesn’t mean flying isn’t broadly safe, but it is a reminder of the importance of regulators holding companies and people accountable if there are breakdowns in equipment or staffing. Harvard researchers have found that the chances of being in a fatal flight accident are one in 11 million, compared to one in 5,000 for a car accident, an indication of how rare such incidents are.

Boeing 737 Max planes have also been the particular subject of safety concerns, including in 2018 and 2019 when countries across the globe grounded planes after Boeing 737 Max 8 planes were involved in two plane crashes that killed hundreds of people. That Boeing is fielding attention yet again underscores the quality control inquiries it has faced about issues including engine construction and design flaws.

The latest examination of the Boeing 737 Max 9 plane comes after the company has dealt with years of critiques about its manufacturing process, including a December 2021 Senate report that called out chronic understaffing and the downplaying of concerns raised by engineers in the company. That report was based off of the testimony of seven whistleblowers — including some who had previously worked at Boeing — who expressed worries about its production practices. This past week, John Barnett, another whistleblower and former Boeing quality control manager died of an apparent suicide — an incident that’s also increased the spotlight on the company.

“Commercial aviation today is safe in all sorts of measurable and immeasurable ways,” Timothy Ravich, an associate professor at the University of Central Florida, told Vox, while adding that “reports of operational concerns — from runway incursions to passenger air rage to pilot training concerns to aircraft production” — have understandably heightened people’s worries about safety. Experts note that it’s vital for regulators to take an aggressive response to these concerns — in the form of groundings, inspections, and, if needed, new rulemakings — to rebuild public trust and prevent such incidents from occurring.

Update, March 13, 5:45 pm ET: This story was originally published on January 8 and has been updated to include information about the FAA investigation.

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