Narrative:

Departed southport, nc, for home field at clt. WX briefing indicated IMC en route, but a temperature inversion at my destination and reported light freezing rain. I decided to go ahead and depart since en route WX was good (IMC, but warm temperature +8 degrees C) and check the clt WX closer. About midway through the 1 hour flight I contacted flight watch and got my destination WX: 500' and 1 mi, temperature 32 degrees, dew point 31, light freezing rain. PIREPS of light to moderate ice at 2000'. At this point I decided to continue my flight rather than divert to an alternate--I had 5 hours fuel--and check the current ATIS at clt and ask the controllers directly about conditions. When instructed by center, I checked ATIS and contacted clt approach. ATIS said the same as flight watch. I asked the controller to confirm the ATIS and give me recent PIREPS. He confirmed the ATIS and began relaying reports from a light transport that would shoot the approach in front of me. He was at 3000' and reported a temperature of +8 degrees C. I was still at cruise altitude, so I would be safe at least down to 3000'. The initial approach altitude for ILS 36R was 2400', so it would probably be above freezing there. Any ice I might accumulate would be descending on the ILS and would probably be confined to the last few hundred ft. The only anti-icing equipment was pitot heat. I elected to continue the approach and watch for signs of ice or freezing rain. At the first sign of significant ice, I would execute a miss, climb to the warmer air above and fly to my alternate. As I was cleared for the approach the tower relayed that the light transport in front of me reported light to moderate ice in freezing rain at 500'. I continued with my plan and shot the ILS. The temperature dropped rapidly and hit 0 degrees C at about 600'. There appeared to be very light drizzle, but no signs of ice accumulation. I broke out at 500', had plenty of visibility and never noticed any ice build up, either on the wings or windshield (pitot heat was on). Landing was uneventful and runway was in good condition. I was not aware the airplane had picked up any ice until I got out to tie it down. I found a 1/16' coating of clear ice on all leading edge surfaces extending back 6-8' from the leading edges. It was so thin and clear I could not see it from the cockpit. My plan worked and I landed safely, but reflection after the flight has convinced me I proceeded unwisely. I now know that freezing rain is the worst form of ice and can disable an airplane quickly. I also now realize that while the aircraft in front of me only reported light to moderate ice, conditions could have changed dramatically during the few mins that separated us on the approach.

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Original NASA ASRS Text

Title: GA SMA ENCOUNTERS ICE BUILD UP ON FINAL APCH.

Narrative: DEPARTED SOUTHPORT, NC, FOR HOME FIELD AT CLT. WX BRIEFING INDICATED IMC ENRTE, BUT A TEMP INVERSION AT MY DEST AND RPTED LIGHT FREEZING RAIN. I DECIDED TO GO AHEAD AND DEPART SINCE ENRTE WX WAS GOOD (IMC, BUT WARM TEMP +8 DEGS C) AND CHK THE CLT WX CLOSER. ABOUT MIDWAY THROUGH THE 1 HR FLT I CONTACTED FLT WATCH AND GOT MY DEST WX: 500' AND 1 MI, TEMP 32 DEGS, DEW POINT 31, LIGHT FREEZING RAIN. PIREPS OF LIGHT TO MODERATE ICE AT 2000'. AT THIS POINT I DECIDED TO CONTINUE MY FLT RATHER THAN DIVERT TO AN ALTERNATE--I HAD 5 HRS FUEL--AND CHK THE CURRENT ATIS AT CLT AND ASK THE CTLRS DIRECTLY ABOUT CONDITIONS. WHEN INSTRUCTED BY CENTER, I CHKED ATIS AND CONTACTED CLT APCH. ATIS SAID THE SAME AS FLT WATCH. I ASKED THE CTLR TO CONFIRM THE ATIS AND GIVE ME RECENT PIREPS. HE CONFIRMED THE ATIS AND BEGAN RELAYING RPTS FROM A LTT THAT WOULD SHOOT THE APCH IN FRONT OF ME. HE WAS AT 3000' AND RPTED A TEMP OF +8 DEGS C. I WAS STILL AT CRUISE ALT, SO I WOULD BE SAFE AT LEAST DOWN TO 3000'. THE INITIAL APCH ALT FOR ILS 36R WAS 2400', SO IT WOULD PROBABLY BE ABOVE FREEZING THERE. ANY ICE I MIGHT ACCUMULATE WOULD BE DSNDING ON THE ILS AND WOULD PROBABLY BE CONFINED TO THE LAST FEW HUNDRED FT. THE ONLY ANTI-ICING EQUIP WAS PITOT HEAT. I ELECTED TO CONTINUE THE APCH AND WATCH FOR SIGNS OF ICE OR FREEZING RAIN. AT THE FIRST SIGN OF SIGNIFICANT ICE, I WOULD EXECUTE A MISS, CLB TO THE WARMER AIR ABOVE AND FLY TO MY ALTERNATE. AS I WAS CLRED FOR THE APCH THE TWR RELAYED THAT THE LTT IN FRONT OF ME RPTED LIGHT TO MODERATE ICE IN FREEZING RAIN AT 500'. I CONTINUED WITH MY PLAN AND SHOT THE ILS. THE TEMP DROPPED RAPIDLY AND HIT 0 DEGS C AT ABOUT 600'. THERE APPEARED TO BE VERY LIGHT DRIZZLE, BUT NO SIGNS OF ICE ACCUMULATION. I BROKE OUT AT 500', HAD PLENTY OF VISIBILITY AND NEVER NOTICED ANY ICE BUILD UP, EITHER ON THE WINGS OR WINDSHIELD (PITOT HEAT WAS ON). LNDG WAS UNEVENTFUL AND RWY WAS IN GOOD CONDITION. I WAS NOT AWARE THE AIRPLANE HAD PICKED UP ANY ICE UNTIL I GOT OUT TO TIE IT DOWN. I FOUND A 1/16' COATING OF CLEAR ICE ON ALL LEADING EDGE SURFACES EXTENDING BACK 6-8' FROM THE LEADING EDGES. IT WAS SO THIN AND CLEAR I COULD NOT SEE IT FROM THE COCKPIT. MY PLAN WORKED AND I LANDED SAFELY, BUT REFLECTION AFTER THE FLT HAS CONVINCED ME I PROCEEDED UNWISELY. I NOW KNOW THAT FREEZING RAIN IS THE WORST FORM OF ICE AND CAN DISABLE AN AIRPLANE QUICKLY. I ALSO NOW REALIZE THAT WHILE THE ACFT IN FRONT OF ME ONLY RPTED LIGHT TO MODERATE ICE, CONDITIONS COULD HAVE CHANGED DRAMATICALLY DURING THE FEW MINS THAT SEPARATED US ON THE APCH.

Data retrieved from NASA's ASRS site as of August 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.