Narrative:

During the takeoff roll; at approximately 90 to 100 KTS my seat slid back to the full back position. Since I was the pilot flying and could no longer control the aircraft I said 'your aircraft; your aircraft' to the captain. The captain took control of the aircraft and rejected the takeoff. In our conversation following the event; the captain stated that he was unsure of the reason I gave him the controls and that he didn't see my seat slide back; he only heard the 'bang' made by my seat hitting the back stop of the track.also; during the seat failure; I momentarily pulled back on the flight controls and was unable to maintain directional control with the rudder pedals. The captain stated that the sound accompanied by the aircraft gyrations caused by the sudden seat shift along with the confusion of being given the aircraft suddenly was what led him to his decision to reject. The reject was uneventful with plenty of stopping margin. We went to a holding area while we confirmed break cooling information and then coordinated a gate return with operations maintenance elected to replace my seat.I normally check my seat once I slide it forward for the final time before flight by pushing back against the pedals. For whatever reason this time; it still let go. I probably could have stated more clearly what had happened to help the captain make a better decision; however; during takeoff there is not much time for a lot of words.

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Original NASA ASRS Text

Title: The Captain of a B737-700 took control and rejected the takeoff when the First Officer; the original pilot flying was unable to control the aircraft due to a failed seat latch which allowed his seat to slide full aft and he was unable to maintain directional control as a result.

Narrative: During the takeoff roll; at approximately 90 to 100 KTS my seat slid back to the full back position. Since I was the pilot flying and could no longer control the aircraft I said 'your aircraft; your aircraft' to the Captain. The Captain took control of the aircraft and rejected the takeoff. In our conversation following the event; the Captain stated that he was unsure of the reason I gave him the controls and that he didn't see my seat slide back; he only heard the 'bang' made by my seat hitting the back stop of the track.Also; during the seat failure; I momentarily pulled back on the flight controls and was unable to maintain directional control with the rudder pedals. The Captain stated that the sound accompanied by the aircraft gyrations caused by the sudden seat shift along with the confusion of being given the aircraft suddenly was what led him to his decision to reject. The reject was uneventful with plenty of stopping margin. We went to a holding area while we confirmed break cooling information and then coordinated a gate return with Operations Maintenance elected to replace my seat.I normally check my seat once I slide it forward for the final time before flight by pushing back against the pedals. For whatever reason this time; it still let go. I probably could have stated more clearly what had happened to help the Captain make a better decision; however; during takeoff there is not much time for a lot of words.

Data retrieved from NASA's ASRS site as of July 2013 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.