Narrative:

At cruise we noticed the airplane turning to the right on its own. We disconnected the autoplt, the controls were stiff. It took both of us to control the airplane. At this point we realized we had jammed controls. We decided to descend to get out of freezing conditions. At 14500 approximately all of a sudden it broke free. Then the controls worked. We decided at this point we would divert to tol. Everything from there on out was okay. Callback conversation with reporter revealed the following information: reporter states there was a maintenance check once on the ground and mechanic believes this was caused by a binding strap which disperses static electricity to the static wicks for discharge. The strap consists of several strands of wire bound together and this particular one was extra long and became bound up in the controls. The strap connects wing and aileron and is seated in a small groove in the aileron and wing. This makes it very difficult to see. Reporter talked about the problem with company safety representative, chief pilot and director of maintenance. They are not 100 percent sure this is the problem but it seems to be the most probable as the strap was quite frayed and only a couple of the wires were still together. The aircraft was an emb 120. The flight crew did declare an emergency. The reason the first thought was of icing is because the aircraft had climbed through the freezing level and had a small amount of rime ice build up the aircraft.

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Original NASA ASRS Text

Title: LTT AT CRUISE HAS ACFT TURNING R WHEN ON AUTOPLT. FIND CTLS JAMMED. DSND DIVERT.

Narrative: AT CRUISE WE NOTICED THE AIRPLANE TURNING TO THE R ON ITS OWN. WE DISCONNECTED THE AUTOPLT, THE CTLS WERE STIFF. IT TOOK BOTH OF US TO CTL THE AIRPLANE. AT THIS POINT WE REALIZED WE HAD JAMMED CTLS. WE DECIDED TO DSND TO GET OUT OF FREEZING CONDITIONS. AT 14500 APPROX ALL OF A SUDDEN IT BROKE FREE. THEN THE CTLS WORKED. WE DECIDED AT THIS POINT WE WOULD DIVERT TO TOL. EVERYTHING FROM THERE ON OUT WAS OKAY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THERE WAS A MAINT CHK ONCE ON THE GND AND MECHANIC BELIEVES THIS WAS CAUSED BY A BINDING STRAP WHICH DISPERSES STATIC ELECTRICITY TO THE STATIC WICKS FOR DISCHARGE. THE STRAP CONSISTS OF SEVERAL STRANDS OF WIRE BOUND TOGETHER AND THIS PARTICULAR ONE WAS EXTRA LONG AND BECAME BOUND UP IN THE CTLS. THE STRAP CONNECTS WING AND AILERON AND IS SEATED IN A SMALL GROOVE IN THE AILERON AND WING. THIS MAKES IT VERY DIFFICULT TO SEE. RPTR TALKED ABOUT THE PROB WITH COMPANY SAFETY REPRESENTATIVE, CHIEF PLT AND DIRECTOR OF MAINT. THEY ARE NOT 100 PERCENT SURE THIS IS THE PROB BUT IT SEEMS TO BE THE MOST PROBABLE AS THE STRAP WAS QUITE FRAYED AND ONLY A COUPLE OF THE WIRES WERE STILL TOGETHER. THE ACFT WAS AN EMB 120. THE FLC DID DECLARE AN EMER. THE REASON THE FIRST THOUGHT WAS OF ICING IS BECAUSE THE ACFT HAD CLBED THROUGH THE FREEZING LEVEL AND HAD A SMALL AMOUNT OF RIME ICE BUILD UP THE 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.