CEN23LA003

The two pilots departed on a business flight with two passengers and observed that the airplane did not pressurize during the initial climb out. As the climb continued, the crew observed a door open warning on the crew alerting system (CAS). The pilot in command (PIC), seated in the right seat, got out of his seat to check the door and attempted to push the handle down toward the locked position, but stated that “it kept coming up.” About 14 seconds after the PIC got out of his seat, the main cabin door opened inflight, which resulted in substantial damage to the door and fuselage. The PIC returned to his seat and commented several times that the second in command (SIC) had not secured the door. The flight returned to land without further incident. Postaccident examination revealed no anomalies that would have prevented the door from a normal sequence of closing, latching, and locking. A corroded/jammed locked sensor assembly was observed that erroneously indicated a locked door to the CAS when the door was actually only latched but not locked. However, the two visual locked indications on the door functioned properly, which was consistent with the crew not fully closing the door or observing the unsafe (red) visual locked indicators. During climb out, the aerodynamic forces on the door and/or airplane vibration likely caused the target for closed door sensor to move away from the sensor, which triggered the CAS door open warning. The aerodynamic forces on the door, airplane vibration, and/or the PIC’s handle movement likely allowed the door to open inflight.

On October 03, 2022, about 1740 central daylight time, an Embraer EMB-545 airplane, N179SP, sustained substantial damage when it was involved in an accident near Houston, Texas. The two pilots and two passengers were uninjured. The airplane was operated under the provisions of Title 14 Code of Federal Regulations Part 91 as a business flight. The PIC, who was seated in the right seat and acting as pilot monitoring, stated that the SIC, who was seated in the left seat and acting as pilot flying, closed and secured the main cabin door. The crew verified that there were no CAS messages displayed on the multifunction display before they taxied for departure and before take-off. The flight data recorder (FDR) data indicated that during initial climb, the airplane was not pressurizing, consistent with the main entry door vent flap being open and the door not fully closed. Climbing through about 5,280 ft, FDR data recorded a DOOR PAX OPEN and master warning indication on the CAS. According to the cockpit voice recorder (CVR) information, the PIC got out of his seat about 12 seconds after the master warning to check the door and reported trying to push the handle down toward the locked position but “it kept coming up”. About 14 seconds after the PIC left his seat, the CVR recorded sounds consistent with the door opening in flight, which resulted in substantial damage to the door and fuselage. The PIC returned to his seat about 21 seconds after the door opened and commented several times that the SIC had not secured the door. The flight returned to land. The door contacted the runway during landing resulting in substantial damage to the airplane. Closure of the main cabin door is accomplished with either the internal or external handle, which transitions the door from the almost closed position to the closed, latched, and locked positions through a complex mechanical mechanism. Operational procedures specify that a pilot check for two visual latched indications (green) and two visual locked indications (green) to ensure the door is fully closed. The CAS system indicates the door is fully closed when the three sensors and targets are all aligned (closed, latched, and locked). Postaccident examination found no anomalies to prevent the door from closing, latching, and locking. Door testing revealed a locked sensor assembly that was jammed due to corrosion, which resulted in a false locked door indication to the CAS when the door was actually in the latched position and not in the locked position. With the handle in the latched position, the two visual locked indications on the door were partially red, showing an accurate status of the door as not locked. Based on the findings of this accident and other similar events, Embraer released a service bulletin recommending a one-time inspection of the door locked sensor and target assembly, then subsequently added a 12-month repetitive inspection of all the sensor and target assemblies to the maintenance program.Embraer also released a flight operations letter describing in further detail the main cabin door closing procedures, as well as developed and implemented in their production line a new sensor and target assembly that mitigates the possibility for jamming.