Narrative:

We were en route and after 2 1/2 hours at 41000 ft we began to experience a problem with the flight controls, specifically the ailerons. We were not able to control the aircraft very well, we had pitch control, but no lateral control. We suspected that moisture on the flight control was frozen. We used the strength of both crew members to keep the plane from rolling by using differential power and rudder. We requested an immediate descent from ATC and a vector to a suitable airport. After we descended through 17000 we were able to break the aileron free and have full control of the aircraft. We requested a vector to airport where we landed. Maintenance there inspected the flight controls and serviced with anti-iced to prevent freezing. I had experienced some mild freezing/problem in this area before and this is somewhat common in this aircraft. By using all our resources and suspecting that a lower altitude would correct the problem we were able to maintain the aircraft. CRM was a vital part of keeping control of the aircraft during descend. Lack of communication with maintenance and a careless attitude about maintenance of the flight controls was a contributing factor. The importance of communication and trust between the flight crew and mechanic in a small operation is imperative. Callback conversation with reporter revealed the following information: the reporter stated this aileron freezing problem on an earlier flight and only took one or two manual aileron inputs to break loose. The reporter stated this event was much different as brute force was required to prevent going inverted and fortunately at lower altitude the ailerons broke loose. The reporter stated the sabreliner has a maintenance procedure that cleans the bellcrank and input rod mechanism and then is sprayed with a anti-freeze solution every 150 hours. The reporter said he believes the time interval needs to be shortened to 50 hours and some terminating action either using bleed air or electrical anti-icing. The reporter said other sabreliner pilots have reported similar icing problems.

Related reports:

Google
 

Original NASA ASRS Text

Title: A SABRELINER 65 IN CRUISE AT FL410 DECLARED AN EMER AND DIVERTED DUE TO LOSS OF AILERON CTL.

Narrative: WE WERE ENRTE AND AFTER 2 1/2 HRS AT 41000 FT WE BEGAN TO EXPERIENCE A PROBLEM WITH THE FLT CTLS, SPECIFICALLY THE AILERONS. WE WERE NOT ABLE TO CTL THE ACFT VERY WELL, WE HAD PITCH CTL, BUT NO LATERAL CTL. WE SUSPECTED THAT MOISTURE ON THE FLT CTL WAS FROZEN. WE USED THE STRENGTH OF BOTH CREW MEMBERS TO KEEP THE PLANE FROM ROLLING BY USING DIFFERENTIAL POWER AND RUDDER. WE REQUESTED AN IMMEDIATE DSCNT FROM ATC AND A VECTOR TO A SUITABLE ARPT. AFTER WE DSNDED THROUGH 17000 WE WERE ABLE TO BREAK THE AILERON FREE AND HAVE FULL CTL OF THE ACFT. WE REQUESTED A VECTOR TO ARPT WHERE WE LANDED. MAINT THERE INSPECTED THE FLT CTLS AND SERVICED WITH ANTI-ICED TO PREVENT FREEZING. I HAD EXPERIENCED SOME MILD FREEZING/PROB IN THIS AREA BEFORE AND THIS IS SOMEWHAT COMMON IN THIS ACFT. BY USING ALL OUR RESOURCES AND SUSPECTING THAT A LOWER ALTITUDE WOULD CORRECT THE PROB WE WERE ABLE TO MAINTAIN THE ACFT. CRM WAS A VITAL PART OF KEEPING CTL OF THE ACFT DURING DSND. LACK OF COM WITH MAINT AND A CARELESS ATTITUDE ABOUT MAINT OF THE FLT CTLS WAS A CONTRIBUTING FACTOR. THE IMPORTANCE OF COM AND TRUST BTWN THE FLT CREW AND MECHANIC IN A SMALL OP IS IMPERATIVE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THIS AILERON FREEZING PROB ON AN EARLIER FLT AND ONLY TOOK ONE OR TWO MANUAL AILERON INPUTS TO BREAK LOOSE. THE RPTR STATED THIS EVENT WAS MUCH DIFFERENT AS BRUTE FORCE WAS REQUIRED TO PREVENT GOING INVERTED AND FORTUNATELY AT LOWER ALTITUDE THE AILERONS BROKE LOOSE. THE RPTR STATED THE SABRELINER HAS A MAINT PROC THAT CLEANS THE BELLCRANK AND INPUT ROD MECHANISM AND THEN IS SPRAYED WITH A ANTI-FREEZE SOLUTION EVERY 150 HRS. THE RPTR SAID HE BELIEVES THE TIME INTERVAL NEEDS TO BE SHORTENED TO 50 HRS AND SOME TERMINATING ACTION EITHER USING BLEED AIR OR ELECTRICAL ANTI-ICING. THE RPTR SAID OTHER SABRELINER PLTS HAVE RPTED SIMILAR ICING PROBS.

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.