Narrative:

Takeoff aborted due to first officer's sliding window opening on takeoff. Crew was rerted upon arrival at dfw, to take a flight to lax due to an equipment swap. The substitute equipment had been undergoing maintenance which included an engine change, for 3 days. Since the flight to lax had already experienced a 3 hour delay, all concerned were in the rush mode. The before start checklist was read, 1 item of which is cockpit windows. These windows are checked by ensuring the handle is in the forward position and the 'closed' flag is in view. The final paperwork, weight data etc, was received and the flight pushed back for departure. Several distrs occurred prior to reaching the departure runway. A new routing by ATC. Incorrect passenger count on the weight data record which required copying new data sent over the company radio frequency (2 pilot crew). The before takeoff checklist was read, 1 item of which is the cockpit windows. During the takeoff roll, I heard air noise coming from the first officer's side of the cockpit and saw the window handle in the aft, or open position. I told him to close the handle, ut he experienced difficulty in moving the handle and it became apparent the window could not be closed by V1 so I aborted the takeoff. The abort was normal and we required no assistance. The first officer later told me he had never opened or closed the window. I then recalled that I never opened or closed the window during training. This was the first officer's second trip.

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Original NASA ASRS Text

Title: FO WINDOW OPEN ON TKOF ROLL, TKOF ABORTED.

Narrative: TKOF ABORTED DUE TO FO'S SLIDING WINDOW OPENING ON TKOF. CREW WAS RERTED UPON ARR AT DFW, TO TAKE A FLT TO LAX DUE TO AN EQUIP SWAP. THE SUBSTITUTE EQUIP HAD BEEN UNDERGOING MAINT WHICH INCLUDED AN ENG CHANGE, FOR 3 DAYS. SINCE THE FLT TO LAX HAD ALREADY EXPERIENCED A 3 HR DELAY, ALL CONCERNED WERE IN THE RUSH MODE. THE BEFORE START CHKLIST WAS READ, 1 ITEM OF WHICH IS COCKPIT WINDOWS. THESE WINDOWS ARE CHKED BY ENSURING THE HANDLE IS IN THE FORWARD POS AND THE 'CLOSED' FLAG IS IN VIEW. THE FINAL PAPERWORK, WT DATA ETC, WAS RECEIVED AND THE FLT PUSHED BACK FOR DEP. SEVERAL DISTRS OCCURRED PRIOR TO REACHING THE DEP RWY. A NEW RTING BY ATC. INCORRECT PAX COUNT ON THE WT DATA RECORD WHICH REQUIRED COPYING NEW DATA SENT OVER THE COMPANY RADIO FREQ (2 PLT CREW). THE BEFORE TKOF CHKLIST WAS READ, 1 ITEM OF WHICH IS THE COCKPIT WINDOWS. DURING THE TKOF ROLL, I HEARD AIR NOISE COMING FROM THE FO'S SIDE OF THE COCKPIT AND SAW THE WINDOW HANDLE IN THE AFT, OR OPEN POS. I TOLD HIM TO CLOSE THE HANDLE, UT HE EXPERIENCED DIFFICULTY IN MOVING THE HANDLE AND IT BECAME APPARENT THE WINDOW COULD NOT BE CLOSED BY V1 SO I ABORTED THE TKOF. THE ABORT WAS NORMAL AND WE REQUIRED NO ASSISTANCE. THE FO LATER TOLD ME HE HAD NEVER OPENED OR CLOSED THE WINDOW. I THEN RECALLED THAT I NEVER OPENED OR CLOSED THE WINDOW DURING TRAINING. THIS WAS THE FO'S SECOND TRIP.

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.