Narrative:

I was the final marshaller on [gate] for arrival flight. I stopped him on the correct line and he set his brakes. I then watched the nose gear tires chocked and gave the tires chocked signal to the pilot. The pilot returned the tires chocked signal. Next thing I see is that the aircraft is rolling back and because of the icy and sandy conditions on the ramp that the chocks are not holding. [Colleague] was able to chock one of the mains on a dry spot after the aircraft had rolled back 3 feet. I was never given the brakes released signal. We towed the aircraft back to the correct parking line.

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Original NASA ASRS Text

Title: Aircraft marshaller reported an aircraft began to slide after being chocked at the gate in icy conditions.

Narrative: I was the final marshaller on [gate] for arrival flight. I stopped him on the correct line and he set his brakes. I then watched the nose gear tires chocked and gave the tires chocked signal to the pilot. The pilot returned the tires chocked signal. Next thing I see is that the aircraft is rolling back and because of the icy and sandy conditions on the ramp that the chocks are not holding. [Colleague] was able to chock one of the mains on a dry spot after the aircraft had rolled back 3 feet. I was never given the brakes released signal. We towed the aircraft back to the correct parking 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.