Narrative:

Entered clouds IFR at sba at 8000', moderate rain, requested and received climb to 10000' where I was on top. Tops of clouds increased to approximately 10500' and as I reentered the clouds I immediately started getting light-moderate mixed icing. I notified center and requested 12000' or lower due to ice!! Center descended us to 8000' where the ice soon dissipated in moderate rain, but the engines began to lose power due to carburetor ice (with full carburetor heat). I advised center of the engine problem and requested lower. Center gave me 7000' MSL, which was the arwy MEA. The engine roughness continues and I declared an emergency, requesting vectors toward lower MEA's or MVA's. Headings toward the salinas valley were given and flown until lower altitudes were available. A descent to 4500' near the king city airport put me below the bases and out of the moisture. I landed west/O further incident at king city airport. In checking the hindsight: I should have insisted on climbing to 12000' where I knew I'd be on top and clear of ice. No one else was reporting ice till I did. All the signs were there with OAT + 0 degrees C and visible moisture (cumulus clouds), but there was a major change in temperature between 8000 and 10000'. Addition of carburetor heat may have aggravated the carburetor icing problem by increasing the temperature to a worse case situation. ATC (center) was not appreciative of the situation until I told them I was declaring an emergency. At that time I was given priority, but they seemed confused as to which way to direct me. Options were sns or paso robles. In extremes a (single pilot IFR) pilot is looking for help and answers, not questions and alternatives. I kept insisting on an vector to lowest MEA/MVA in point of time not distance.

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Original NASA ASRS Text

Title: GA SMT INFLT ENCOUNTER WITH WX ENGINE ICE. DECLARES AN EMERGENCY TO GET FLTASSIST TO AREA WHERE LOWER ALT IS POSSIBLE.

Narrative: ENTERED CLOUDS IFR AT SBA AT 8000', MODERATE RAIN, REQUESTED AND RECEIVED CLB TO 10000' WHERE I WAS ON TOP. TOPS OF CLOUDS INCREASED TO APPROX 10500' AND AS I REENTERED THE CLOUDS I IMMEDIATELY STARTED GETTING LIGHT-MODERATE MIXED ICING. I NOTIFIED CENTER AND REQUESTED 12000' OR LOWER DUE TO ICE!! CENTER DSNDED US TO 8000' WHERE THE ICE SOON DISSIPATED IN MODERATE RAIN, BUT THE ENGS BEGAN TO LOSE PWR DUE TO CARB ICE (WITH FULL CARB HEAT). I ADVISED CENTER OF THE ENG PROB AND REQUESTED LOWER. CENTER GAVE ME 7000' MSL, WHICH WAS THE ARWY MEA. THE ENG ROUGHNESS CONTINUES AND I DECLARED AN EMER, REQUESTING VECTORS TOWARD LOWER MEA'S OR MVA'S. HDGS TOWARD THE SALINAS VALLEY WERE GIVEN AND FLOWN UNTIL LOWER ALTS WERE AVAILABLE. A DSCNT TO 4500' NEAR THE KING CITY ARPT PUT ME BELOW THE BASES AND OUT OF THE MOISTURE. I LANDED W/O FURTHER INCIDENT AT KING CITY ARPT. IN CHKING THE HINDSIGHT: I SHOULD HAVE INSISTED ON CLBING TO 12000' WHERE I KNEW I'D BE ON TOP AND CLR OF ICE. NO ONE ELSE WAS RPTING ICE TILL I DID. ALL THE SIGNS WERE THERE WITH OAT + 0 DEGS C AND VISIBLE MOISTURE (CUMULUS CLOUDS), BUT THERE WAS A MAJOR CHANGE IN TEMP BTWN 8000 AND 10000'. ADDITION OF CARB HEAT MAY HAVE AGGRAVATED THE CARB ICING PROB BY INCREASING THE TEMP TO A WORSE CASE SITUATION. ATC (CENTER) WAS NOT APPRECIATIVE OF THE SITUATION UNTIL I TOLD THEM I WAS DECLARING AN EMER. AT THAT TIME I WAS GIVEN PRIORITY, BUT THEY SEEMED CONFUSED AS TO WHICH WAY TO DIRECT ME. OPTIONS WERE SNS OR PASO ROBLES. IN EXTREMES A (SINGLE PLT IFR) PLT IS LOOKING FOR HELP AND ANSWERS, NOT QUESTIONS AND ALTERNATIVES. I KEPT INSISTING ON AN VECTOR TO LOWEST MEA/MVA IN POINT OF TIME NOT DISTANCE.

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.