A B737-700 incurred outboard engine cowling C duct damage when the leading edge devices were inadver...

Attributes
ACN	571831
Time
Date	200301
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Environment
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	ground : maintenance
Person 1
Affiliation	company : air carrier
Function	maintenance : technician
Qualification	technician : airframe technician : powerplant
ASRS Report	571831
Person 2
Affiliation	company : air carrier
Function	maintenance : technician
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper documentation maintenance problem : improper maintenance non adherence : published procedure non adherence : company policies non adherence : far
Independent Detector	other other : person 1
Resolutory Action	none taken : detected after the fact
Consequence	other other other
Factors
Maintenance	contributing factor : manuals contributing factor : work cards performance deficiency : inspection performance deficiency : logbook entry performance deficiency : non compliance with legal requirements performance deficiency : scheduled maintenance
Supplementary
Problem Areas	Chart Or Publication Aircraft Maintenance Human Performance
Primary Problem	Maintenance Human Performance
Situations
Publication	Leading Edge Slat Safety

Narrative:

I was told to close the circuit breakers in the east&east bay, we were getting ready to push the aircraft out for engine idles, when I pushed the standby hydraulic circuit breaker in, the pump came on, and the leading edges came down on the outboard G duct, there was no one in the cockpit at the time, when someone went upstairs to turn the pump off, they found the standby switch in the armed position from the B/C check the night before, and the leading edge lockout pin had already been removed from the valve in the main wheel well.

Original NASA ASRS Text

Title: A B737-700 INCURRED OUTBOARD ENG COWLING C DUCT DAMAGE WHEN THE LEADING EDGE DEVICES WERE INADVERTENTLY EXTENDED.

Narrative: I WAS TOLD TO CLOSE THE CIRCUIT BREAKERS IN THE E&E BAY, WE WERE GETTING READY TO PUSH THE ACFT OUT FOR ENG IDLES, WHEN I PUSHED THE STANDBY HYD CIRCUIT BREAKER IN, THE PUMP CAME ON, AND THE LEADING EDGES CAME DOWN ON THE OUTBOARD G DUCT, THERE WAS NO ONE IN THE COCKPIT AT THE TIME, WHEN SOMEONE WENT UPSTAIRS TO TURN THE PUMP OFF, THEY FOUND THE STANDBY SWITCH IN THE ARMED POS FROM THE B/C CHK THE NIGHT BEFORE, AND THE LEADING EDGE LOCKOUT PIN HAD ALREADY BEEN REMOVED FROM THE VALVE IN THE MAIN WHEEL WELL.

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.

A B737-700 incurred outboard engine cowling C duct damage when the leading edge devices were inadvertently extended.