Narrative:

I was on an instrument flight from fld direct ste, radar vectors to rcx. Cruising at 4000 ft on top of the clouds at 38 degree F, approximately 10 DME northwest of ste, center informed me they lost radar contact and to report abeam mdz. Approximately 25 DME northwest of ste I encountered higher ceilings of approximately 6500 ft. As I entered the clouds level at 4000 ft, I noticed that I was seeing moisture developing on the wings and windshield, as well as the temperature was lowering quickly below freezing. I notified center that I was beginning to pick up some ice. I asked for lower hoping to either find higher temperatures or VFR conditions, but center could only let me down to 3600 ft. I lowered to 3600 ft, was still picking up ice, center wanted me to do the NDB approach into mdz, but I declined as I was not prepared for the approach. I quickly decided and announced I was doing a 180 degree turn and climbing. Center cleared me to do whatever I needed to do. I firewalled throttle, mixture and propeller, was able to climb to clear conditions above 6500 ft, leveled at 7500 ft and 38 degree F temperatures. After 5-10 mins, all the ice burned off, center gave me a 7000-8000 ft block altitude and asked for my intentions. After contacting flight watch, I decided to proceed to rcx and negotiated with center to stay at 7500 ft. They cleared me for the approach, no ice encountered. In retrospect, due to the 38 degree F temperature prior to entering the clouds, I was very surprised how quickly the temperature dropped in the clouds, something I will never forget to anticipate in the future. Also to be more prepared to make an emergency approach in the future.

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Original NASA ASRS Text

Title: AN SMA FOUND HIMSELF IN UNFORECASTED ICING.

Narrative: I WAS ON AN INST FLT FROM FLD DIRECT STE, RADAR VECTORS TO RCX. CRUISING AT 4000 FT ON TOP OF THE CLOUDS AT 38 DEG F, APPROX 10 DME NW OF STE, CTR INFORMED ME THEY LOST RADAR CONTACT AND TO RPT ABEAM MDZ. APPROX 25 DME NW OF STE I ENCOUNTERED HIGHER CEILINGS OF APPROX 6500 FT. AS I ENTERED THE CLOUDS LEVEL AT 4000 FT, I NOTICED THAT I WAS SEEING MOISTURE DEVELOPING ON THE WINGS AND WINDSHIELD, AS WELL AS THE TEMP WAS LOWERING QUICKLY BELOW FREEZING. I NOTIFIED CTR THAT I WAS BEGINNING TO PICK UP SOME ICE. I ASKED FOR LOWER HOPING TO EITHER FIND HIGHER TEMPS OR VFR CONDITIONS, BUT CTR COULD ONLY LET ME DOWN TO 3600 FT. I LOWERED TO 3600 FT, WAS STILL PICKING UP ICE, CTR WANTED ME TO DO THE NDB APCH INTO MDZ, BUT I DECLINED AS I WAS NOT PREPARED FOR THE APCH. I QUICKLY DECIDED AND ANNOUNCED I WAS DOING A 180 DEG TURN AND CLBING. CTR CLRED ME TO DO WHATEVER I NEEDED TO DO. I FIREWALLED THROTTLE, MIXTURE AND PROP, WAS ABLE TO CLB TO CLR CONDITIONS ABOVE 6500 FT, LEVELED AT 7500 FT AND 38 DEG F TEMPS. AFTER 5-10 MINS, ALL THE ICE BURNED OFF, CTR GAVE ME A 7000-8000 FT BLOCK ALT AND ASKED FOR MY INTENTIONS. AFTER CONTACTING FLT WATCH, I DECIDED TO PROCEED TO RCX AND NEGOTIATED WITH CTR TO STAY AT 7500 FT. THEY CLRED ME FOR THE APCH, NO ICE ENCOUNTERED. IN RETROSPECT, DUE TO THE 38 DEG F TEMP PRIOR TO ENTERING THE CLOUDS, I WAS VERY SURPRISED HOW QUICKLY THE TEMP DROPPED IN THE CLOUDS, SOMETHING I WILL NEVER FORGET TO ANTICIPATE IN THE FUTURE. ALSO TO BE MORE PREPARED TO MAKE AN EMER APCH IN THE FUTURE.

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.