The Alaska Airlines Boeing that lost its door mid-flight was missing four propellers.

Four propellers were missing from an Alaska Airlines Boeing 737 Max 9 that experienced problems during the flight, according to a preliminary report released this Wednesday by the North American Transportation Safety Board (NTSB).

According to the NTSB, the plane was missing four propellers and shortly after takeoff on Jan. 5, while flying with 117 people on board at an altitude of approximately 4,876 meters, it lost a door, forcing the plane to ditch. emergency landing after takeoff in Portland, Oregon.

This door was used to block the exit and was not intended to be opened as this model already has sufficient emergency exits in this configuration.

Four screws were missing from the panel because they apparently had not been replaced at Boeing’s plant in Renton, Washington, the federal agency tasked with investigating transportation accidents concluded.

The report does not specify who removed the screws or what part of the company was responsible for replacing them.

To confirm the panel’s condition, the NTSB provided a photograph of the panel, which shows three of the four screws missing. The area where the fourth screw should be installed appears closed.

Due to the incident with the Alaska Airlines plane, the US Federal Aviation Administration (FAA) ordered the grounding of all Boeing 737 aircraft.

The FAA committed five years ago to strengthen oversight of the plane maker following two deadly crashes that also involved Boeing Max planes.

In this context, the North American aircraft manufacturer has accumulated losses over five years, first due to the 737 Max crisis and then due to the economic crisis caused by the Covid-19 pandemic, to which the 737 Max shock was recently added. Max 9.