Narrative:

Normal procedure is to have the APU running and powering the electrical system, then upon setting the parking brake, shut down both engines. This is also the procedure on some terminating flts, but not this one. On this flight the procedure is to shut down only 1 engine until ground power is available, then shut down the other engine. What happened was I accidentally shut down both engines, with no APU, thereby putting the aircraft on only battery/emergency power. I realized this immediately, but could only wait for ground power. I did, however, inadvertently and without realizing it reintroduce fuel to the engines. This caused fuel to flow into the hot engine and with a temperature outside of 32 degrees F created a big white cloud of fuel steam/smoke. This was thought to be a fire by ground personnel, who advised me of a fire in the #2 engine, partially through passenger deplaning I ordered an evacuate/evacuation. I then began the evacuate/evacuation checklist and noticed the fuel levers at idle, not cutoff. I moved them quickly to cutoff and the smoke immediately stopped and the evacuate/evacuation was canceled. Passenger had already opened both overwing exits and were on the wings, as well as, a flight attendant had blown a slide at door 2R and passenger were evacing down it. No one was hurt and no damage was caused, only 1 slide was used. This may have been prevented if the procedure was to call for the copilot to shut down the engines on command. That way both pilots would be in the loop about which engines were to be shut down and one pilot could question the other if one or both was the best/proper decision for the situation.

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Original NASA ASRS Text

Title: A B737-500 PARKED AT THE GATE DECLARED AN EMER AND EVACED THE ACFT DUE TO A PERCEIVED ENG FIRE CAUSED BY THE FUEL START LEVERS BEING MOVED FROM CUTOFF TO IDLE ALLOWING FUEL INTO THE HOT ENGS WITH RESULTING FUEL VAPOR AND SMOKE.

Narrative: NORMAL PROC IS TO HAVE THE APU RUNNING AND POWERING THE ELECTRICAL SYS, THEN UPON SETTING THE PARKING BRAKE, SHUT DOWN BOTH ENGS. THIS IS ALSO THE PROC ON SOME TERMINATING FLTS, BUT NOT THIS ONE. ON THIS FLT THE PROC IS TO SHUT DOWN ONLY 1 ENG UNTIL GND PWR IS AVAILABLE, THEN SHUT DOWN THE OTHER ENG. WHAT HAPPENED WAS I ACCIDENTALLY SHUT DOWN BOTH ENGS, WITH NO APU, THEREBY PUTTING THE ACFT ON ONLY BATTERY/EMER PWR. I REALIZED THIS IMMEDIATELY, BUT COULD ONLY WAIT FOR GND PWR. I DID, HOWEVER, INADVERTENTLY AND WITHOUT REALIZING IT REINTRODUCE FUEL TO THE ENGS. THIS CAUSED FUEL TO FLOW INTO THE HOT ENG AND WITH A TEMP OUTSIDE OF 32 DEGS F CREATED A BIG WHITE CLOUD OF FUEL STEAM/SMOKE. THIS WAS THOUGHT TO BE A FIRE BY GND PERSONNEL, WHO ADVISED ME OF A FIRE IN THE #2 ENG, PARTIALLY THROUGH PAX DEPLANING I ORDERED AN EVAC. I THEN BEGAN THE EVAC CHKLIST AND NOTICED THE FUEL LEVERS AT IDLE, NOT CUTOFF. I MOVED THEM QUICKLY TO CUTOFF AND THE SMOKE IMMEDIATELY STOPPED AND THE EVAC WAS CANCELED. PAX HAD ALREADY OPENED BOTH OVERWING EXITS AND WERE ON THE WINGS, AS WELL AS, A FLT ATTENDANT HAD BLOWN A SLIDE AT DOOR 2R AND PAX WERE EVACING DOWN IT. NO ONE WAS HURT AND NO DAMAGE WAS CAUSED, ONLY 1 SLIDE WAS USED. THIS MAY HAVE BEEN PREVENTED IF THE PROC WAS TO CALL FOR THE COPLT TO SHUT DOWN THE ENGS ON COMMAND. THAT WAY BOTH PLTS WOULD BE IN THE LOOP ABOUT WHICH ENGS WERE TO BE SHUT DOWN AND ONE PLT COULD QUESTION THE OTHER IF ONE OR BOTH WAS THE BEST/PROPER DECISION FOR THE SIT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.