EMER DECLARED WHEN THE AUTOPLT WAS INADVERTENTLY SWITCHED ON.

Narrative

ON OCT/SUN/94 AT ABOUT PM00 IN A 1974 CESSNA 182P; AFTER COMPLETING A THOROUGH PREFLT AND RUNUP; I DEPARTED FROM RWY 30 AT ANP. THE DEP WAS NORMAL; I CLBED TO 2000 FT AND CONTACTED BWI APCH ON 119.0. I ASKED FOR CLRNC INTO THE CLASS B AIRSPACE WITH MY DEST BEING GAI. AFTER I GOT A SQUAWK CODE; I REQUESTED 2500 FT AND A CHANGE OF DEST TO CARROLL COUNTY (W54). THE CTLR TOLD ME TO TURN TO A HDG OF 340 DEGS; AS I STARTED MY TURN TO THE R I NOTICED THE CTLS FELT STRANGE. THE YOKE WAS FLUTTERING CONSIDERABLY. I FELT LIKE I WAS FIGHTING TO KEEP THE PLANE FLYING STRAIGHT AND LEVEL. I CALLED BWI TO REQUEST A TURN BACK TO ANP; I FELT LIKE AN AILERON WAS LOOSE. I LOOKED OUT THE WINDOWS AND SAW THAT THE AILERONS WERE BOTH ON THE PLANE AND THERE WAS NOTHING HANGING FROM THE WINGS (BECAUSE THAT IS WHAT THE FLUTTERING YOKE FELT LIKE). BEFORE BWI COULD ANSWER MY CALL; I STARTED TO MAKE A VERY SLOW SHALLOW SKIDDING TURN WITH THE RUDDER. BWI CALLED ME AND I PROCEEDED TO TELL THEM I HAD A PROB. I SAID I WASN'T SURE WHAT WAS WRONG BUT I FELT LIKE I WAS ABOUT TO LOSE A CTL SURFACE. I SAID I WAS GOING BACK TO ANP AND I WASN'T SURE IF I WOULD MAKE IT. THE CTLR ASKED ME IF I NEEDED ASSISTANCE; I REPLIED NO I HAVE THE RWY IN SIGHT. I WAS ON A LONG FINAL FOR RWY 12 AT ANP. I WAS INSTRUCTED TO CHANGE TO 122.9 AND CONTACT THE BWI TWR UPON LNDG. I THEN DECLARED AN EMER AT ANP. I TOLD THE TFC I WOULD BE LNDG ON RWY 12 AND TO PLEASE CLR THE PATTERN. EVERYONE COMPLIED AND; WHILE FIGHTING THE PLANE; I WAS ABLE TO MAKE AN UNEVENTFUL LNDG. I PROCEEDED TO THE MAINT HANGAR WHERE A MECH MET ME AND CHKED THE PLANE OVER WHILE I CALLED THE BWI TWR. THE MECH SAW NOTHING THAT WAS APPARENT TO HIM TO CAUSE SUCH SYMPTOMS. I WAS ABOUT TO LEAVE THE PLANE WITH HIM TO CHK OUT WHEN A PERSON WHO HEARD MY STORY CAME OVER AND TOLD ME HE ONCE EXPERIENCED THE SAME SYMPTOMS. HE ASKED ME IF I HAD AN AUTOPLT. I SAID YES AND CHKED THE POS OF THE SWITCHES. THE AUTOPLT HAD BEEN ACTIVATED INADVERTENTLY. THIS AUTOPLT HAS BEEN INOP FOR AS LONG AS I HAVE BEEN FLYING THIS PLANE (3 YRS). SOMEHOW THE AUTOPLT WAS ACTIVATED PROBABLY WHEN I SET THE XPONDER CODE (THE AUTOPLT IS DIRECTLY BELOW THE XPONDER). WHEN THE AUTOPLT KICKED ON; THE WING LEVELER OR HDG HOLDER TOOK OVER AND TRIED TO CTL THE PLANE. SINCE I HAVE NEVER FLOWN A PLANE WHILE UNDER AUTOPLT CTL; I HAD NO IDEA HOW THE CTLS WOULD FEEL TO FIGHT WITH THE AUTOPLT. AFTER TURNING OFF THE AUTOPLT; I WENT UP IN THE PATTERN. WHEN I WAS ON THE DOWNWIND LEG; I TURNED ON THE AUTOPLT AND GOT THE SAME SYMPTOMS I HAD EXPERIENCED EARLIER. I FELT PRETTY EMBARRASSED BY THE EVENT; BUT I DID LEARN ONE LESSON FROM IT. I LEARNED THAT UNDER WHAT I THOUGHT WERE EMER CONDITIONS I KEPT MY WITS ABOUT ME AND FLEW THE PLANE TO A SAFE LNDG.