Narrative:

Upon advancing throttles for takeoff, I noticed a hissing sound from the captain's side window - window appeared closed and locked. Hissing sound worsened and I elected to discontinue the takeoff roll at approximately 70 KTS. I cleared the runway. Confirmed that the window was closed and locked (it was). Reopened and reseated the window and proceeded without incident. Can only guess that the window was not seated properly initially.

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Original NASA ASRS Text

Title: TKOF ABORTED ACCOUNT CAPT'S SLIDING WINDOW WAS NOT SEATED CORRECTLY. ACFT EQUIP OPERATING PROCS.

Narrative: UPON ADVANCING THROTTLES FOR TKOF, I NOTICED A HISSING SOUND FROM THE CAPT'S SIDE WINDOW - WINDOW APPEARED CLOSED AND LOCKED. HISSING SOUND WORSENED AND I ELECTED TO DISCONTINUE THE TKOF ROLL AT APPROX 70 KTS. I CLRED THE RWY. CONFIRMED THAT THE WINDOW WAS CLOSED AND LOCKED (IT WAS). REOPENED AND RESEATED THE WINDOW AND PROCEEDED WITHOUT INCIDENT. CAN ONLY GUESS THAT THE WINDOW WAS NOT SEATED PROPERLY INITIALLY.

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.