Narrative:

Departed KC61 on an IFR flight plan with destination of ict. Received WX brief for planned route from dtn and planned flight at 4000 ft MSL (freezing level forecast at 6000 ft and above). While en route at 4000 ft MSL, 15-20 NM west of the fam VOR, outside air temperature dropped to 0 degrees C and precipitation turned from rain to ice pellets. Requested lower to 3000 ft MSL and was approved to descend. After leveling to 3000 ft MSL, outside air temperature decreased to -3 degrees C. Aircraft began accumulating ice (light to moderate). Attempted contact with ATC but due to other traffic, no contact was possible. I began a 180 degree escape maneuver to get out of the icing condition. Passing 90 degrees of turn, I was able to communicate with ATC and inform him of my actions. The controller informed me that while IFR, I must always inform him first before taking any action or deviating from a clearance. This was just preaching to the choir. I had to make the turn immediately to prevent a dangerous situation from developing. I am not sure what other action could have been taken as PIC under these circumstances. I landed at the nearest available airport (fam) and went home the next day.

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Original NASA ASRS Text

Title: HDG TRACK DEV WHEN A GA PLT MAKES A 180 DEG TURN TO ESCAPE THE ICE FORMATIONS BUILDING ON HIS ACFT NEAR FAM, MO.

Narrative: DEPARTED KC61 ON AN IFR FLT PLAN WITH DEST OF ICT. RECEIVED WX BRIEF FOR PLANNED RTE FROM DTN AND PLANNED FLT AT 4000 FT MSL (FREEZING LEVEL FORECAST AT 6000 FT AND ABOVE). WHILE ENRTE AT 4000 FT MSL, 15-20 NM W OF THE FAM VOR, OUTSIDE AIR TEMP DROPPED TO 0 DEGS C AND PRECIP TURNED FROM RAIN TO ICE PELLETS. REQUESTED LOWER TO 3000 FT MSL AND WAS APPROVED TO DSND. AFTER LEVELING TO 3000 FT MSL, OUTSIDE AIR TEMP DECREASED TO -3 DEGS C. ACFT BEGAN ACCUMULATING ICE (LIGHT TO MODERATE). ATTEMPTED CONTACT WITH ATC BUT DUE TO OTHER TFC, NO CONTACT WAS POSSIBLE. I BEGAN A 180 DEG ESCAPE MANEUVER TO GET OUT OF THE ICING CONDITION. PASSING 90 DEGS OF TURN, I WAS ABLE TO COMMUNICATE WITH ATC AND INFORM HIM OF MY ACTIONS. THE CTLR INFORMED ME THAT WHILE IFR, I MUST ALWAYS INFORM HIM FIRST BEFORE TAKING ANY ACTION OR DEVIATING FROM A CLRNC. THIS WAS JUST PREACHING TO THE CHOIR. I HAD TO MAKE THE TURN IMMEDIATELY TO PREVENT A DANGEROUS SIT FROM DEVELOPING. I AM NOT SURE WHAT OTHER ACTION COULD HAVE BEEN TAKEN AS PIC UNDER THESE CIRCUMSTANCES. I LANDED AT THE NEAREST AVAILABLE ARPT (FAM) AND WENT HOME THE NEXT DAY.

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.