Narrative:

We rejected our takeoff at approximately 120 knots after an uncommanded nose up pitch at 115 knots. Our bugged vr speed was approximately 143 knots. I was the pilot flying and when the nose started to pitch up uncommanded; I felt the aircraft was not in a normal flight configuration; being approximately 30 knots below vr and initiated the reject. The captain took control of the aircraft as we rejected straight ahead. At a safe taxi speed; we exited the runway while I made the 'remain seated' call. Once we came to a stop on the parallel taxiway; we ran the rejected takeoff checklist. We then referenced the rejected T/O (take-off) brake cooling chart in the QRH and determined we had a brake cooling time of approximately 57 minutes with the taxi in. We elected to return to the gate and coordinated as such with operations and maintenance. It was during this time that we noticed the T/O trim setting was in a nose up trim configuration that was near the limit of the green band. We had run the before take-off checklist and had not caught that incorrect setting; and since it was still within the takeoff band did not get a takeoff configuration warning when tested as part of the before take-off checklist. Upon return to the gate; we wrote up the rejected takeoff and discussed the event with maintenance personnel. The captain kept the passengers informed of the situation and also contacted the [chief pilot]. One side note; when we began our take off roll we did get a speed brake lever do not arm light. However; it went out and we deemed it spurious. All other operations up to that point had been normal.

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Original NASA ASRS Text

Title: B737 flight crew reported rejecting the takeoff at approximately 120 kts when the aircraft began to pitch up. It was later determined the stab trim was incorrectly set to an excessive nose up setting.

Narrative: We rejected our takeoff at approximately 120 knots after an uncommanded nose up pitch at 115 knots. Our bugged Vr speed was approximately 143 knots. I was the pilot flying and when the nose started to pitch up uncommanded; I felt the aircraft was not in a normal flight configuration; being approximately 30 knots below Vr and initiated the reject. The Captain took control of the aircraft as we rejected straight ahead. At a safe taxi speed; we exited the runway while I made the 'Remain seated' call. Once we came to a stop on the parallel taxiway; we ran the Rejected Takeoff checklist. We then referenced the Rejected T/O (Take-off) Brake Cooling chart in the QRH and determined we had a brake cooling time of approximately 57 minutes with the taxi in. We elected to return to the gate and coordinated as such with Operations and Maintenance. It was during this time that we noticed the T/O trim setting was in a nose up trim configuration that was near the limit of the green band. We had run the Before Take-Off checklist and had not caught that incorrect setting; and since it was still within the takeoff band did not get a takeoff configuration warning when tested as part of the Before Take-Off checklist. Upon return to the gate; we wrote up the rejected takeoff and discussed the event with maintenance personnel. The Captain kept the passengers informed of the situation and also contacted the [Chief Pilot]. One side note; when we began our take off roll we did get a Speed Brake Lever Do Not Arm light. However; it went out and we deemed it spurious. All other operations up to that point had been normal.

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.