A piece of the Alaska Airlines plane that fell off mid-flight lands in a backyard

The Boeing 737 Max 9 that took off from Portland, Ore., bound for Ontario, Calif., returned to the airport with all its passengers unharmed. Authorities are investigating what cause the incident.

The 177 people (171 passengers and six crew members) who were aboard Alaska Airlines Flight 1282 last Friday will never forget what their flight. Half an hour after the flight from Portland, Ore., to Ontario, Calif., took off, a loud bang was heard, and one of the emergency windows had depressurized in mid-flight and part of the plane went flying off.

From inside, a teddy bear, a passenger’s shirt and a cell phone also flew out, as The Wall Street Journal reported. The reasons for the accident seemed to be a mystery, but a piece has just appeared that could determine what happened during the accident: the window plug. This was stated on Sunday by National Transportation Safety Board President Jennifer Homendy.

Homendy assured in a press conference that the object they had found would be m vital in the investigation to explain why the emergency window exploded mid-flight, endangering everyone on board:

Our structural team will want to see everything on the window: all components of the window to see any witness marks, any paint transfer, the condition of the window when they found it. That can tell you a lot about what happened.

Furthermore, she explained, the piece was found near Portland, specifically in the backyard of a school teacher named Bob. "We are very happy that Bob found this," she said.

Problems prior to the Alaska Airlines plane crash

The accident caused Alaska Airlines to provisionally withdraw all Boeing 737 Max 9s and Boeing 737 Max 8s. Other airlines received the same order. This was stated by a spokesperson for the Federal Aviation Administration (FAA) who explained that the planes of this model would be grounded until the organization was "satisfied that they are safe."

The plane had problems prior to the explosion. The National Transportation Safety Board reported up to three previous problems regarding depressurization on the aircraft between Dec. 7 and Jan. 4, one recorded mid-flight.

The pilots also reported failures in their headphones. According to statements reported by CBS, the first officer had a malfunction in his headphones. Not only that, the captain lost communication in his headphones too. This forced both of them to communicate through the ceiling speaker, since they could not hear anything with the damaged headphones.