Incident Overview
Shortly after pushback from gate B-8, crew noticed that the handle for the number 2 engine door 2 right was not flush. The engine was shut down, and ground maintenance personnel closed the door from the outside. Immediately after, the cabin began to fill with dense smoke.
Evacuation
Attempts by the captain to obtain a jetway—using radio and an open window—were unsuccessful, as no jetway operator was present and ground personnel are not cross-trained to operate a jetway. The crew and passengers evacuated using slides. The flight had received clearance to proceed to gate B-20 for the evacuation.
Findings
Investigation later determined that the battery bus relay (R1) and battery transfer relay (R2) had failed. When the number 2 engine was shut down, the electrical transfer system picked up the load. The flightcrew did not power the right bus from the auxiliary power unit (APU).