Narrative:

Upon arrival at ZZZ, captain abc and first officer wxwx left the aircraft to file their flight plan at base operations. I remained on board to conduct my preflight duties. While in the cockpit in the flight engineer seat, an air carrier maintenance employee zxzx came into the cockpit and requested that I lower the leading edge flap to allow maintenance to change a landing light. I lowered the flap by electrical system. I moved the flap arm switch to 'arm' position and all directional switches to down position. The leading edge flap green light illuminated indicating that all leading edge flaps were extended. Zxzx left the cockpit and I resumed my preflight duties. A short time later, xyxy came into the cockpit and started adp and moved flap lever to 10 degree position. I left the cockpit and went outside to observe what transpired. I later learned that zxzx had been injured while changing the landing light. Supplemental information from acn 454540: after operating as flight engineer on air carrier flight xyz fra-ZZZ, I was resting in the upper deck cabin during the ground time before departure. At or about XF00Z, someone came running up the stairs yelling, 'lower the slats, he's caught in the slats.' I immediately proceeded into the cockpit. I immediately placed the flap handle to the 10 degree position and turned on the adp's on. I do not recall if I turned the APU bleed on or if it was already on. I later learned mechanic zxzx was seriously injured.

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Original NASA ASRS Text

Title: A B747-200 DURING REPLACEMENT OF THE L INBOARD LNDG LIGHT LAMP THE LEADING EDGE DEVICES WERE RETRACTED INCURRING SERIOUS INJURY TO THE TECHNICIAN.

Narrative: UPON ARR AT ZZZ, CAPT ABC AND FO WXWX LEFT THE ACFT TO FILE THEIR FLT PLAN AT BASE OPS. I REMAINED ON BOARD TO CONDUCT MY PREFLT DUTIES. WHILE IN THE COCKPIT IN THE FE SEAT, AN ACR MAINT EMPLOYEE ZXZX CAME INTO THE COCKPIT AND REQUESTED THAT I LOWER THE LEADING EDGE FLAP TO ALLOW MAINT TO CHANGE A LNDG LIGHT. I LOWERED THE FLAP BY ELECTRICAL SYS. I MOVED THE FLAP ARM SWITCH TO 'ARM' POS AND ALL DIRECTIONAL SWITCHES TO DOWN POS. THE LEADING EDGE FLAP GREEN LIGHT ILLUMINATED INDICATING THAT ALL LEADING EDGE FLAPS WERE EXTENDED. ZXZX LEFT THE COCKPIT AND I RESUMED MY PREFLT DUTIES. A SHORT TIME LATER, XYXY CAME INTO THE COCKPIT AND STARTED ADP AND MOVED FLAP LEVER TO 10 DEG POS. I LEFT THE COCKPIT AND WENT OUTSIDE TO OBSERVE WHAT TRANSPIRED. I LATER LEARNED THAT ZXZX HAD BEEN INJURED WHILE CHANGING THE LNDG LIGHT. SUPPLEMENTAL INFO FROM ACN 454540: AFTER OPERATING AS FE ON ACR FLT XYZ FRA-ZZZ, I WAS RESTING IN THE UPPER DECK CABIN DURING THE GND TIME BEFORE DEP. AT OR ABOUT XF00Z, SOMEONE CAME RUNNING UP THE STAIRS YELLING, 'LOWER THE SLATS, HE'S CAUGHT IN THE SLATS.' I IMMEDIATELY PROCEEDED INTO THE COCKPIT. I IMMEDIATELY PLACED THE FLAP HANDLE TO THE 10 DEG POS AND TURNED ON THE ADP'S ON. I DO NOT RECALL IF I TURNED THE APU BLEED ON OR IF IT WAS ALREADY ON. I LATER LEARNED MECH ZXZX WAS SERIOUSLY INJURED.

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.