Narrative:

I departed swf into overcast clouds approximately 1300 ft MSL. I was on an IFR flight plan and had a WX briefing. I was aware that there was an airmet for icing. I had PIREPS that the tops were just over 6000 ft. My thoughts were to climb to clear skies above to avoid prolonged exposure to potential icing. Consequently, I filed for 8000 ft. On the climb out, I picked up some light rime ice on the wings and advised ATC. They told me they would have higher in the next sector. I was level at 6000 ft. After waiting for several mins, I asked again for higher and was told unable. The plane began to shake and vibrate. My first thought was that I was having engine trouble, but when I saw the ice fling from the propeller, I realized I had accumulated icing on the propeller. I called ATC and again asked for higher. They refused and I declared an emergency. They then changed my vector by 90 degrees and cleared me to higher. Once out of the clouds, I decided to change my destination to an airport with higher ceilings and drove the rest of my trip.

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Original NASA ASRS Text

Title: AN M20 SINGLE PLT CLBING IFR ENCOUNTERED ICING CONDITIONS, DECLARED AN EMER, AND LANDED AT AN ALTERNATE ARPT.

Narrative: I DEPARTED SWF INTO OVCST CLOUDS APPROX 1300 FT MSL. I WAS ON AN IFR FLT PLAN AND HAD A WX BRIEFING. I WAS AWARE THAT THERE WAS AN AIRMET FOR ICING. I HAD PIREPS THAT THE TOPS WERE JUST OVER 6000 FT. MY THOUGHTS WERE TO CLB TO CLR SKIES ABOVE TO AVOID PROLONGED EXPOSURE TO POTENTIAL ICING. CONSEQUENTLY, I FILED FOR 8000 FT. ON THE CLBOUT, I PICKED UP SOME LIGHT RIME ICE ON THE WINGS AND ADVISED ATC. THEY TOLD ME THEY WOULD HAVE HIGHER IN THE NEXT SECTOR. I WAS LEVEL AT 6000 FT. AFTER WAITING FOR SEVERAL MINS, I ASKED AGAIN FOR HIGHER AND WAS TOLD UNABLE. THE PLANE BEGAN TO SHAKE AND VIBRATE. MY FIRST THOUGHT WAS THAT I WAS HAVING ENG TROUBLE, BUT WHEN I SAW THE ICE FLING FROM THE PROP, I REALIZED I HAD ACCUMULATED ICING ON THE PROP. I CALLED ATC AND AGAIN ASKED FOR HIGHER. THEY REFUSED AND I DECLARED AN EMER. THEY THEN CHANGED MY VECTOR BY 90 DEGS AND CLRED ME TO HIGHER. ONCE OUT OF THE CLOUDS, I DECIDED TO CHANGE MY DEST TO AN ARPT WITH HIGHER CEILINGS AND DROVE THE REST OF MY TRIP.

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.