Narrative:

Waited outside of gate area for several minutes for self park system to light up. It turned on with green light; and as we were pulling into the gate; lights went completely dark for a second or two. As captain applied the brakes to stop; system came back on with yellow light for several seconds; then turned completely off. By this time we were completely stopped. I looked out the side window and saw a ground personnel with the light controller in his hand; partially disassembled; and he was working on it with a screwdriver. He saw me looking at him; and then turned around and pushed the emergency stop button on the wall behind him. Self park light system then went from completely off to red. We came to find out we were 2-3 feet past the stop line. Ground crew hooked up tug and pushed the aircraft back to the line.

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Original NASA ASRS Text

Title: B747 flight crew reported parking at a gate with a self park system that was providing erratic guidance while they were parking; resulting in an overshoot of the intended stop point.

Narrative: Waited outside of gate area for several minutes for self park system to light up. It turned on with green light; and as we were pulling into the gate; lights went completely dark for a second or two. As Captain applied the brakes to stop; system came back on with yellow light for several seconds; then turned completely off. By this time we were completely stopped. I looked out the side window and saw a ground personnel with the light controller in his hand; partially disassembled; and he was working on it with a screwdriver. He saw me looking at him; and then turned around and pushed the emergency stop button on the wall behind him. Self park light system then went from completely off to red. We came to find out we were 2-3 feet past the stop line. Ground crew hooked up tug and pushed the aircraft back to the line.

Data retrieved from NASA's ASRS site 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.