Narrative:

I was working aircraft troubleshooting a right engine bleed trip light. We had already fixed the left bleed problem when we were ready to taxi the aircraft to the station for a high power run to see if the parts we changed (450 degree sensor; pre-cooler control sensor and 490 degree overheat switch) would fix the problem. We got clearance and had a co-worker clear us for engine start. We got both engines running at idle and was getting ready to call the tower for clearance. I remembered from the past engine run to check if the aural warning circuit breaker had been reset. I leaned over the center console to check the circuit breaker behind the P-6 panel and unknowingly advanced the throttles to approximately 55-60% takeoff power. I heard the engines spool up and quickly reached for the throttles and pulled them back to idle. We then heard the tower say there was some debris flying around behind us. We then shut down the engines and went investigating and found the spare engine cowl damaged.

Google
 

Original NASA ASRS Text

Title: A B737-700 AFTER ENG START AND RUNNING AT IDLE; TECHNICIAN TURNED TO CHK AURAL WARNING CIRCUIT BREAKER AND INADVERTENTLY ADVANCED THRUST LEVERS TO PART PWR CAUSING DAMAGE TO A SPARE ENG COWLING STORED BEHIND ACFT.

Narrative: I WAS WORKING ACFT TROUBLESHOOTING A R ENG BLEED TRIP LIGHT. WE HAD ALREADY FIXED THE L BLEED PROB WHEN WE WERE READY TO TAXI THE ACFT TO THE STATION FOR A HIGH PWR RUN TO SEE IF THE PARTS WE CHANGED (450 DEG SENSOR; PRE-COOLER CTL SENSOR AND 490 DEG OVERHEAT SWITCH) WOULD FIX THE PROB. WE GOT CLRNC AND HAD A CO-WORKER CLR US FOR ENG START. WE GOT BOTH ENGS RUNNING AT IDLE AND WAS GETTING READY TO CALL THE TWR FOR CLRNC. I REMEMBERED FROM THE PAST ENG RUN TO CHK IF THE AURAL WARNING CIRCUIT BREAKER HAD BEEN RESET. I LEANED OVER THE CTR CONSOLE TO CHK THE CIRCUIT BREAKER BEHIND THE P-6 PANEL AND UNKNOWINGLY ADVANCED THE THROTTLES TO APPROX 55-60% TKOF PWR. I HEARD THE ENGS SPOOL UP AND QUICKLY REACHED FOR THE THROTTLES AND PULLED THEM BACK TO IDLE. WE THEN HEARD THE TWR SAY THERE WAS SOME DEBRIS FLYING AROUND BEHIND US. WE THEN SHUT DOWN THE ENGS AND WENT INVESTIGATING AND FOUND THE SPARE ENG COWL DAMAGED.

Data retrieved from NASA's ASRS site as of January 2009 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.