Narrative:

On a flight from ZZZ1 to ZZZ; I was in a piper seneca I. The route of flight was direct at 7000 ft MSL. Cloud tops were around 5000 ft MSL. I broke out of the clouds with trace rime ice out of ZZZ1. Center cleared descent at pilot's discretion to 2800 ft MSL. I followed a rate of around 1000 FPM to 2800 ft MSL. I picked up moderate rime ice in the descent. Once at 2800 ft MSL ATC informed me to climb to 3000 ft MSL. 3000 ft MSL is the minimum altitude for the approach until 14 DME. I informed ATC I was unable to stay at 3000 ft due to the ice buildup. The aircraft had accumulated around 1/8 - 1/4 inch of rime ice by this point. I requested a descent to 2500 ft MSL to get to warmer temperatures to avoid additional ice buildup. ATC advised they could not allow that legally. I was outbound to VOR at 2800 ft MSL and the ice kept building. I informed ATC I was unable to comply with instructions. They asked what I needed. I said; 'I want to turn 360 degrees and proceed inbound at 2000 ft MSL (MDA for current segment).' I performed what was stated I was going to do. I followed the 144 degree radial off the VOR inbound and descended to 2000 ft MSL. At this point the ice began to melt off the leading edges and wind screen. I landed with less than 1/8 inch of ice on aircraft. I didn't realize the ice would be building since ZZZ1 was 2000 ft overcast at time of departure.

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Original NASA ASRS Text

Title: AN IFR PIPER SENECA PILOT ENCOUNTERED ICING DURING DESCENT AND APCH. IN VIOLATION OF HIS CLRNC HE DSNDED TO 2000 FT MSL TO MELT ICE.

Narrative: ON A FLT FROM ZZZ1 TO ZZZ; I WAS IN A PIPER SENECA I. THE RTE OF FLT WAS DIRECT AT 7000 FT MSL. CLOUD TOPS WERE AROUND 5000 FT MSL. I BROKE OUT OF THE CLOUDS WITH TRACE RIME ICE OUT OF ZZZ1. CTR CLRED DSCNT AT PLT'S DISCRETION TO 2800 FT MSL. I FOLLOWED A RATE OF AROUND 1000 FPM TO 2800 FT MSL. I PICKED UP MODERATE RIME ICE IN THE DSCNT. ONCE AT 2800 FT MSL ATC INFORMED ME TO CLB TO 3000 FT MSL. 3000 FT MSL IS THE MINIMUM ALT FOR THE APCH UNTIL 14 DME. I INFORMED ATC I WAS UNABLE TO STAY AT 3000 FT DUE TO THE ICE BUILDUP. THE ACFT HAD ACCUMULATED AROUND 1/8 - 1/4 INCH OF RIME ICE BY THIS POINT. I REQUESTED A DSCNT TO 2500 FT MSL TO GET TO WARMER TEMPS TO AVOID ADDITIONAL ICE BUILDUP. ATC ADVISED THEY COULD NOT ALLOW THAT LEGALLY. I WAS OUTBOUND TO VOR AT 2800 FT MSL AND THE ICE KEPT BUILDING. I INFORMED ATC I WAS UNABLE TO COMPLY WITH INSTRUCTIONS. THEY ASKED WHAT I NEEDED. I SAID; 'I WANT TO TURN 360 DEGS AND PROCEED INBOUND AT 2000 FT MSL (MDA FOR CURRENT SEGMENT).' I PERFORMED WHAT WAS STATED I WAS GOING TO DO. I FOLLOWED THE 144 DEG RADIAL OFF THE VOR INBOUND AND DSNDED TO 2000 FT MSL. AT THIS POINT THE ICE BEGAN TO MELT OFF THE LEADING EDGES AND WIND SCREEN. I LANDED WITH LESS THAN 1/8 INCH OF ICE ON ACFT. I DIDN'T REALIZE THE ICE WOULD BE BUILDING SINCE ZZZ1 WAS 2000 FT OVCST AT TIME OF DEP.

Data retrieved from NASA's ASRS site as of May 2009 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.