Narrative:

On my first post-INS chkride flight in IMC, I was returning to luk from mwo (approximately 1/2 hour flight). I had picked up light ice on the way out and had made a PIREP. I picked up some light to moderate mixed ice en route at 3000' MSL. An aircraft ahead of me on the approach reported heavy ice buildup from 2700' on down to 1700'. As I was vectored for the approach, the ice started to build very rapidly. By the time I was established on the approach (outside of the beacon), I was at full power and barely maintaining altitude at less than 80 KIAS. I attempted to remain above the G/south, but could not. I advised luk tower that I would descend to 1700' (100' above the MDA for the localizer approach), which is where the previous aircraft had reported ice buildup ceasing. However I continued to build ice. I also had to keep carburetor heat full on and play with RPM's to loosen propeller ice. I had advised tower and approach several times of my situation (but of course they could not help). Approximately 3 mi inside mde I double-checked the bases and made my decision to descend to 1400' (200' below the MDA). I made this choice because, with the way the ice was building, I was going down anyway, and because of the fact that I am very familiar with the area. As I broke out at 1400' tower asked my altitude. I responded, '1400' out of the clouds.' I had visibility contact with the airport and new exactly my position (I reported a local shopping center to my right). By the time I reached the airport, some ice had sublimated, but very little. In a full stall landing I was 3-4 KIAS slower than I have been on the approach. I would not have made the decision to descend below the MDA if I had not been very familiar with the airport. When I had received my briefing for this flight, there were no pilot reports of ice in the area. Yet from discussing the incident with controllers and ground crew, numerous aircraft had come in with ice. 2 things would have made me take the bus home: greater stress on the hazards of icing during INS flying, and PIREPS in the area.

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Original NASA ASRS Text

Title: GA SMA ENCOUNTERED ICE ON APCH TO LUK AND DESCENDED BELOW MDA TO GET CLEAR OF CLOUDS.

Narrative: ON MY FIRST POST-INS CHKRIDE FLT IN IMC, I WAS RETURNING TO LUK FROM MWO (APPROX 1/2 HR FLT). I HAD PICKED UP LIGHT ICE ON THE WAY OUT AND HAD MADE A PIREP. I PICKED UP SOME LIGHT TO MODERATE MIXED ICE ENRTE AT 3000' MSL. AN ACFT AHEAD OF ME ON THE APCH RPTED HEAVY ICE BUILDUP FROM 2700' ON DOWN TO 1700'. AS I WAS VECTORED FOR THE APCH, THE ICE STARTED TO BUILD VERY RAPIDLY. BY THE TIME I WAS ESTABLISHED ON THE APCH (OUTSIDE OF THE BEACON), I WAS AT FULL PWR AND BARELY MAINTAINING ALT AT LESS THAN 80 KIAS. I ATTEMPTED TO REMAIN ABOVE THE G/S, BUT COULD NOT. I ADVISED LUK TWR THAT I WOULD DSND TO 1700' (100' ABOVE THE MDA FOR THE LOC APCH), WHICH IS WHERE THE PREVIOUS ACFT HAD RPTED ICE BUILDUP CEASING. HOWEVER I CONTINUED TO BUILD ICE. I ALSO HAD TO KEEP CARB HEAT FULL ON AND PLAY WITH RPM'S TO LOOSEN PROP ICE. I HAD ADVISED TWR AND APCH SEVERAL TIMES OF MY SITUATION (BUT OF COURSE THEY COULD NOT HELP). APPROX 3 MI INSIDE MDE I DOUBLE-CHKED THE BASES AND MADE MY DECISION TO DSND TO 1400' (200' BELOW THE MDA). I MADE THIS CHOICE BECAUSE, WITH THE WAY THE ICE WAS BUILDING, I WAS GOING DOWN ANYWAY, AND BECAUSE OF THE FACT THAT I AM VERY FAMILIAR WITH THE AREA. AS I BROKE OUT AT 1400' TWR ASKED MY ALT. I RESPONDED, '1400' OUT OF THE CLOUDS.' I HAD VIS CONTACT WITH THE ARPT AND NEW EXACTLY MY POS (I RPTED A LCL SHOPPING CENTER TO MY RIGHT). BY THE TIME I REACHED THE ARPT, SOME ICE HAD SUBLIMATED, BUT VERY LITTLE. IN A FULL STALL LNDG I WAS 3-4 KIAS SLOWER THAN I HAVE BEEN ON THE APCH. I WOULD NOT HAVE MADE THE DECISION TO DSND BELOW THE MDA IF I HAD NOT BEEN VERY FAMILIAR WITH THE ARPT. WHEN I HAD RECEIVED MY BRIEFING FOR THIS FLT, THERE WERE NO PLT RPTS OF ICE IN THE AREA. YET FROM DISCUSSING THE INCIDENT WITH CTLRS AND GND CREW, NUMEROUS ACFT HAD COME IN WITH ICE. 2 THINGS WOULD HAVE MADE ME TAKE THE BUS HOME: GREATER STRESS ON THE HAZARDS OF ICING DURING INS FLYING, AND PIREPS IN THE AREA.

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.