AN E145 CREW EXPERIENCED PITCH TRIM PROBLEMS AND AN UNCONTROLLED CLIMB FROM ROTATION TO 6300 FT. DECLARED EMER AND RETURNED TO LAND.

Narrative

ON TKOF BOTH THE CAPT AND I (I AM A LINE HOLDING CAPT IN THE R SEAT) FOUND NONE OF THE PITCH TRIM SETTING SWITCHES WERE WORKING. WE WENT INTO AN UNCONTROLLED CLIMB WITH CTLS FULL FORWARD. WE WERE UNABLE TO USE CHKLISTS BECAUSE OF THE DIFFICULTY IN CTLING THE CLIMB. WE BROKE THE CLIMB ABOVE ASSIGNED ALT OF 3000 FT. WE LEVELED OFF AT OR AROUND 6300 FT AND AIRSPEED INCREASED TO 260 KTS. I HAND FLEW THE ACFT BACK TO ZZZ (WITH VECTORS-IMC) TO LAND. AN EMER WAS DECLARED AROUND 3000 FT. I DON'T KNOW WHAT CAUSED THIS INCIDENT; BUT I DO WANT TRAINING TO AVOID IT IF IT HAPPENS AGAIN. THE ENTIRE EVENT WAS UNCONTROLLED AND I'M LUCKY TO HAVE LANDED THE ACFT WITHOUT ANY DAMAGE. ALL SET UP CHKS WERE DONE AND ALL SWITCHES WERE TESTED. ONCE AGAIN; I HAVE NO IDEA WHAT CAUSED THIS INCIDENT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT SHORTLY AFTER ROTATION THE CAP DECLARED NO STABILIZER TRIM AND TO TAKEOVER. THE RPTR SAID THE STABILIZER TRIM WAS ALSO INOPERATIVE FROM MY YOKE SWITCHES AND THE YOKES WERE NOW PUSHED FORWARD TO EXTREME LIMITS. THE RPTR STATED THE AIRPLANE WAS CLIMBING AT A 20 DEG ANGLE; 6000 FT PER MIN; AND WAS 5 KTS FROM A STALL. THE RPTR SAID THEY STOPPED THE CLIMB AT 6300 FT AND AIRSPEED INCREASED TO 260 KTS AND AT THAT TIME HEARD A NOISE AND SOME TRIM WAS REGAINED. THE RPTR STATED ON LNDG NEITHER THE MAIN ELECTRIC TRIM NOR THE AUXILIARY TRIM ACTUATORS OPERATED. THE RPTR SAID MAINT HAS RELEASED NO INFO TO THE CREW ON THE FIX OR THE FAILED COMPONENTS. CALLBACK FROM ACN 538931: THE RPTR STATED THAT ON TKOF THE HORIZONTAL TRIM MOVED 2 TO 3 UNITS GREATER THAN THE SETTING FOR TKOF AND CLIMB AND COULD NOT BE CORRECTED WITH THE YOKE SWITCHES. THE RPTR SAID ALL HANDS WERE REQUIRED PUSHING FORWARD ON THE YOKES TO ARREST THE CLIMB. THE RPTR STATED THIS HORIZONTAL STABILIZER FAILURE TO TRIM IN CLIMB IS A RECURRING PROB AND IS SERIOUS. THE RPTR SAID MAINT REPLACED BOTH YOKE SWITCHES AND THE MAIN ELECTRIC TRIM ACTUATOR AND WERE SENT OUT FOR TEST AND EVALUATION.