Narrative:

Aircraft gate return after vertical stabilizer pitot static cover was spotted from another aircraft at airport. A walk around check was accomplished [early in the morning] during heavy fog and limited visibility condition after the aircraft was wet washed during the early morning hours pitot cover flag was facing out the grey dark color side that made it harder to spot installation on aircraft.

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Original NASA ASRS Text

Title: Line Technician reported a B737 returned to the gate due to a pitot static cover not being removed prior to departure.

Narrative: Aircraft gate return after vertical stabilizer pitot static cover was spotted from another aircraft at airport. A walk around check was accomplished [early in the morning] during heavy fog and limited visibility condition after the aircraft was wet washed during the early morning hours pitot cover flag was facing out the grey dark color side that made it harder to spot installation on aircraft.

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.