DC10 FLC HAS PROB WITH CTLS ON DSCNT. THE SPD BRAKES ARE STIFF AND AUTOPLT DOES NOT ROLL OUT ON HEADING. IT TURNS OUT THERE WAS ICE ON THE CTL CABLES.

Narrative

THIS IS A DESCRIPTION OF FLT CTL ICING. THERE JUST HAPPENED TO BE AN FAA MAINT INSPECTOR JUMP SEATING ON THIS FLT; HE IS OUR COMPANY'S DC10 INSPECTOR. HE HAD SPENT THE NIGHT IN THE AREA AND WAS AWARE OF THE PREVIOUS NIGHT'S WX. HE CAME UP WITH THE FOLLOWING EXPLANATION OF WHAT MIGHT HAVE CAUSED THIS PROB. DURING THE NIGHT THERE WERE EASTERLY WINDS WHICH BROUGHT RAIN. THIS RAIN WAS DRIVEN UP THE TAIL OF THE ACFT ENTERING THE WINGS FROM THE REAR. THIS ALLOWED WATER TO GET IN THE BOXES THAT ENCLOSE THE CTL CABLES AND PULLEYS; WHICH LATER FROZE UP. I WAS FLYING THE ACFT ON THE AUTOPLT; THE FLT UP TO THE APCH PHASE HAD BEEN NORMAL AND UNEVENTFUL. DURING APCH WE WERE BEING VECTORED TO RWY 21R AT DTW. ATC GAVE US A DSCNT; A TURN AND A SPD REDUCTION. AFTER ESTABLISHING THE DSCNT AND TURN; I EXTENDED THE SPD BRAKES TO START SLOWING. THE SPD BRAKES FELT STIFF GOING PAST 1/3 EXTENSION SO I RETRACTED AND RE-EXTENDED AND THEY FELT NORMAL THE SECOND TIME. THE AUTOPLT DID NOT APPEAR TO ROLL OUT SO I WATCHED IT CLOSELY AND BY 5 DEGS PRIOR TO HEADING I WAS SURE IT WAS NOT GOING TO ROLL OUT. I DISCONNECTED AND ATTEMPTED TO MANUALLY ROLL OUT. IT TOOK CONSIDERABLE FORCE TO MOVE THE YOKE. AT FIRST IT FELT AS IF IT WAS SLIPPING; BUT THE ACFT DID NOT ROLL OUT WITH MORE FORCE AND ABOUT 2/3 DEFLECTION (CONSIDERABLY MORE THAN NORMAL) THE CTLS APPEARED TO BREAK FREE. AFTER THIS THE ACFT RESPONDED AND FLEW NORMALLY; INCLUDING THE AUTOPLT. I ESTABLISHED THE ACFT ON THE ASSIGNED HEADING; FLEW THE APCH AND LNDG; UNEVENTFULLY. MAINT INSPECTED; DETECTED AND REMOVED THE ICE FROM THE CTL CABLES AND PULLEYS. THIS APPEARS TO BE A UNIQUE OCCURRENCE; HOWEVER OUR MAINT INSPECTOR WAS GOING TO MAKE SURE OUR MAINT PEOPLE WOULD BE AWARE OF AND PREPARED FOR THE SIT IN THE FUTURE.