Narrative:

Departing runway 32L; we made a normal thrust takeoff in clear conditions on a bare; dry runway with temperature at -10 degrees C. The aircraft weight was just under 59000 pounds. Assigned a heading of 270 degrees after takeoff. Takeoff was normal and the captain (PF) made his initial turn. During the turn we were switched to departure; a 400 ft call was made by PNF; autoplt engaged; flaps retracted and a switch to another controller was made. During this time a series of abnormalities occurred. While the first officer was communicating and setting altitudes; one or more caution messages appeared on the EICAS screen. There were no associated chimes or master warning or master caution annunciations. Considering our altitude and location the PNF continued to accomplish his normal tasks for the moment. At about this point; the captain (PF) asked the PNF to select his 'stabilizer trim disc' yoke switch. Not realizing there was a problem; the PNF queried the PF for clarification. I did not know that the PF had already attempted to disconnect the stabilizer trim and his autoplt disconnect switch from his control yoke unsuccessfully. Both switches were unresponsive. I then selected the stabilizer trim without my hands on the yoke. The autoplt disengaged when the first officer selected his stabilizer trim disc switch. The aircraft started a rapid pitch up and was climbing at a rate that was clearly going to exceed our altitude clearance limit of 5000 ft. I observed the PF was exerting considerable control pressure to arrest the rapid climb. The PNF declared an emergency and stated to ZZZ departure that we were having a control problem and climbing. With the captain's stabilizer and autoplt disconnect switch unresponsive; he could not silence the associated autoplt alarm. The PNF selected his disconnect switches to silence the alarm. The captain can now control the aircraft but only by exerting considerable forward pressure on the controls. Captain commands to reengage the trims and I reengage the stabilizer and mach trims. It should be noted that stabilizer trim ch 2 was in the depressed; unlit position with the stabilizer trim 2 caution message displayed. I pushed several times on the apparently stuck switch and was able to get all of the trims back on line and functioning. The aircraft was now under control and everything functioning; except the autoplt which would not engage. QRH procedures were read for stabilizer and mach trim messages; flight attendants and passenger addressed; emergency canceled and flight continued to ZZZ1. Maintenance called en route. Normal landing. Callback conversation with reporter revealed the following information: reporter advised that just prior to the disconnect; the stabilizer trim reading was 4.4 units and unmoving. He stated the normal position would have been roughly 7.5 units. He stated the recovery took them approximately 1200 ft above their cleared altitude. He was unable to recall exactly what EICAS messages were that preceded the incident although he suspects they were likely stabilizer trim related. He had no information concerning maintenance action which resulted.

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Original NASA ASRS Text

Title: FLT CREW OF CRJ-700 EXPERIENCED TEMPORARY LOSS OF PITCH AXIS CTL DURING CLB OUT FROM ZZZ.

Narrative: DEPARTING RWY 32L; WE MADE A NORMAL THRUST TKOF IN CLR CONDITIONS ON A BARE; DRY RWY WITH TEMPERATURE AT -10 DEGS C. THE ACFT WT WAS JUST UNDER 59000 LBS. ASSIGNED A HDG OF 270 DEGS AFTER TKOF. TKOF WAS NORMAL AND THE CAPT (PF) MADE HIS INITIAL TURN. DURING THE TURN WE WERE SWITCHED TO DEP; A 400 FT CALL WAS MADE BY PNF; AUTOPLT ENGAGED; FLAPS RETRACTED AND A SWITCH TO ANOTHER CTLR WAS MADE. DURING THIS TIME A SERIES OF ABNORMALITIES OCCURRED. WHILE THE FO WAS COMMUNICATING AND SETTING ALTS; ONE OR MORE CAUTION MESSAGES APPEARED ON THE EICAS SCREEN. THERE WERE NO ASSOCIATED CHIMES OR MASTER WARNING OR MASTER CAUTION ANNUNCIATIONS. CONSIDERING OUR ALT AND LOCATION THE PNF CONTINUED TO ACCOMPLISH HIS NORMAL TASKS FOR THE MOMENT. AT ABOUT THIS POINT; THE CAPT (PF) ASKED THE PNF TO SELECT HIS 'STAB TRIM DISC' YOKE SWITCH. NOT REALIZING THERE WAS A PROBLEM; THE PNF QUERIED THE PF FOR CLARIFICATION. I DID NOT KNOW THAT THE PF HAD ALREADY ATTEMPTED TO DISCONNECT THE STAB TRIM AND HIS AUTOPLT DISCONNECT SWITCH FROM HIS CTL YOKE UNSUCCESSFULLY. BOTH SWITCHES WERE UNRESPONSIVE. I THEN SELECTED THE STAB TRIM WITHOUT MY HANDS ON THE YOKE. THE AUTOPLT DISENGAGED WHEN THE FO SELECTED HIS STAB TRIM DISC SWITCH. THE ACFT STARTED A RAPID PITCH UP AND WAS CLBING AT A RATE THAT WAS CLEARLY GOING TO EXCEED OUR ALT CLRNC LIMIT OF 5000 FT. I OBSERVED THE PF WAS EXERTING CONSIDERABLE CTL PRESSURE TO ARREST THE RAPID CLB. THE PNF DECLARED AN EMER AND STATED TO ZZZ DEP THAT WE WERE HAVING A CTL PROBLEM AND CLBING. WITH THE CAPT'S STAB AND AUTOPLT DISCONNECT SWITCH UNRESPONSIVE; HE COULD NOT SILENCE THE ASSOCIATED AUTOPLT ALARM. THE PNF SELECTED HIS DISCONNECT SWITCHES TO SILENCE THE ALARM. THE CAPT CAN NOW CTL THE ACFT BUT ONLY BY EXERTING CONSIDERABLE FORWARD PRESSURE ON THE CTLS. CAPT COMMANDS TO REENGAGE THE TRIMS AND I REENGAGE THE STAB AND MACH TRIMS. IT SHOULD BE NOTED THAT STAB TRIM CH 2 WAS IN THE DEPRESSED; UNLIT POSITION WITH THE STAB TRIM 2 CAUTION MESSAGE DISPLAYED. I PUSHED SEVERAL TIMES ON THE APPARENTLY STUCK SWITCH AND WAS ABLE TO GET ALL OF THE TRIMS BACK ON LINE AND FUNCTIONING. THE ACFT WAS NOW UNDER CTL AND EVERYTHING FUNCTIONING; EXCEPT THE AUTOPLT WHICH WOULD NOT ENGAGE. QRH PROCS WERE READ FOR STAB AND MACH TRIM MESSAGES; FLT ATTENDANTS AND PAX ADDRESSED; EMER CANCELED AND FLT CONTINUED TO ZZZ1. MAINT CALLED ENRTE. NORMAL LNDG. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR ADVISED THAT JUST PRIOR TO THE DISCONNECT; THE STAB TRIM READING WAS 4.4 UNITS AND UNMOVING. HE STATED THE NORMAL POSITION WOULD HAVE BEEN ROUGHLY 7.5 UNITS. HE STATED THE RECOVERY TOOK THEM APPROX 1200 FT ABOVE THEIR CLRED ALT. HE WAS UNABLE TO RECALL EXACTLY WHAT EICAS MESSAGES WERE THAT PRECEDED THE INCIDENT ALTHOUGH HE SUSPECTS THEY WERE LIKELY STAB TRIM RELATED. HE HAD NO INFO CONCERNING MAINT ACTION WHICH RESULTED.

Data retrieved from NASA's ASRS site as of January 2009 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.