Sequence of Events
After the airplane had taxied to and stopped at the gate, the jetway was positioned to the left door. While passengers were beginning to deplane, the captain positioned the fuel levers to the 'cutoff' position. Ground power had not yet been connected, and the airplane went dark. The captain then repositioned the fuel levers to the 'idle' position.
Immediately following this action, ground personnel noticed smoke coming from the number two engine and notified the flight crew of a fire. The captain ordered an evacuation and began the checklist procedures.
Checklist and Resolution
When the flight crew reached the position of the fuel levers step in the checklist, the captain noticed that the fuel levers were in the 'idle' position. The captain then positioned the fuel levers to the 'cutoff' position. The smoke began to dissipate from the engine, and the all clear signal was given by the ground crew. After the smoke dissipated, the captain cancelled the evacuation.
Passenger Egress
Approximately 20 passengers had deplaned via the right slide to the ground. Another 10 to 20 passengers went out the over wing exit.
Maintenance Findings
Maintenance personnel inspected the engine and reported that there was no indication of an actual fire. They suspected that when the fuel lever was positioned to the 'idle' position, the fuel valve opened and jet fuel was injected into the hot decelerating engine, causing the observed smoke.