Narrative:

On takeoff copilot's sliding window came unlatched. Takeoff aborted at 120 KTS (V1=140 KTS). The window had not indicated it was not latched until well into the takeoff roll. Maintenance was unable to fix window latching mechanism so the aircraft was removed from service.

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Original NASA ASRS Text

Title: TKOF ABORTED WHEN FO'S SLIDING WINDOW BECOMES UNLATCHED ON TKOF ON A NIGHT OP.

Narrative: ON TKOF COPLT'S SLIDING WINDOW CAME UNLATCHED. TKOF ABORTED AT 120 KTS (V1=140 KTS). THE WINDOW HAD NOT INDICATED IT WAS NOT LATCHED UNTIL WELL INTO THE TKOF ROLL. MAINT WAS UNABLE TO FIX WINDOW LATCHING MECHANISM SO THE ACFT WAS REMOVED FROM SVC.

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.