Narrative:

Tested pitch trim switch system during the before start checklist, as per company procedures, no abnormalities detected. Deiced prior to gate departure at approximately XA10 local. Upon takeoff from runway 32L at ord approximately XA25 local, trimmed aircraft prior to 160 KTS, as per company procedures. As aircraft accelerated, a noticeable pitch-up force was felt in control column. First officer's pitch trim switch seemed to have no effect on increasing control column forces. Scanned and verified no movement of pitch trim indicator on EICAS during pitch trim switch actuation. Pitch trim had remained at the 7 unit setting prior to takeoff. Immediately slowed the aircraft to 160 KTS to relieve control forces and informed captain of apparent pitch trim failure. Attempted to actuate pitch trim system with backup pitch trim switch, had no effect. EICAS warning message, 'pitch trim, 1-2 degrees inoperative.' then received confirming failure of system. Captain attempted to actuate captain's pitch trim switch, had no effect. Aom consulted and ATC notified by captain while I continued to fly aircraft. Airspeed maintained at 160 KTS, flaps 9 degrees, allowed for acceptable aircraft control. Aircraft difficult to control above 170 KTS. Captain accomplished aom procedure and pitch trim system restored to normal. Contacted maintenance controller for additional information. Supplemental information from acn 606235: all trim function was restored and after conferring with maintenance controller, we proceeded to mdt. Maintenance said if any further problems encountered, there was a maintenance team in mdt with another aircraft.

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Original NASA ASRS Text

Title: EMJ CREW HAD A PITCH TRIM FAILURE DEPARTING ORD. THE CAPT FOLLOWED AOM PROCS AND WAS ABLE TO RESTORE THE SYS TO OP AND CONTINUED TO PLANNED DEST.

Narrative: TESTED PITCH TRIM SWITCH SYS DURING THE BEFORE START CHKLIST, AS PER COMPANY PROCS, NO ABNORMALITIES DETECTED. DEICED PRIOR TO GATE DEP AT APPROX XA10 LCL. UPON TKOF FROM RWY 32L AT ORD APPROX XA25 LCL, TRIMMED ACFT PRIOR TO 160 KTS, AS PER COMPANY PROCS. AS ACFT ACCELERATED, A NOTICEABLE PITCH-UP FORCE WAS FELT IN CTL COLUMN. FO'S PITCH TRIM SWITCH SEEMED TO HAVE NO EFFECT ON INCREASING CTL COLUMN FORCES. SCANNED AND VERIFIED NO MOVEMENT OF PITCH TRIM INDICATOR ON EICAS DURING PITCH TRIM SWITCH ACTUATION. PITCH TRIM HAD REMAINED AT THE 7 UNIT SETTING PRIOR TO TKOF. IMMEDIATELY SLOWED THE ACFT TO 160 KTS TO RELIEVE CTL FORCES AND INFORMED CAPT OF APPARENT PITCH TRIM FAILURE. ATTEMPTED TO ACTUATE PITCH TRIM SYS WITH BACKUP PITCH TRIM SWITCH, HAD NO EFFECT. EICAS WARNING MESSAGE, 'PITCH TRIM, 1-2 DEGS INOP.' THEN RECEIVED CONFIRMING FAILURE OF SYS. CAPT ATTEMPTED TO ACTUATE CAPT'S PITCH TRIM SWITCH, HAD NO EFFECT. AOM CONSULTED AND ATC NOTIFIED BY CAPT WHILE I CONTINUED TO FLY ACFT. AIRSPD MAINTAINED AT 160 KTS, FLAPS 9 DEGS, ALLOWED FOR ACCEPTABLE ACFT CTL. ACFT DIFFICULT TO CTL ABOVE 170 KTS. CAPT ACCOMPLISHED AOM PROC AND PITCH TRIM SYS RESTORED TO NORMAL. CONTACTED MAINT CTLR FOR ADDITIONAL INFO. SUPPLEMENTAL INFO FROM ACN 606235: ALL TRIM FUNCTION WAS RESTORED AND AFTER CONFERRING WITH MAINT CTLR, WE PROCEEDED TO MDT. MAINT SAID IF ANY FURTHER PROBS ENCOUNTERED, THERE WAS A MAINT TEAM IN MDT WITH ANOTHER ACFT.

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.