Narrative:

I was going to fly from O04 to lar to accompany my mother to an eye operation. I have made this trip many times before and felt confident that I cold make it in nearly any situation. I called FSS the night before to check WX and was told that the front that had passed through carson that day would present some problems with mountain obscuration, low ceilings, and a freezing level just above the MEA. They also told me to expect icing in clouds. I was told that due to a strong dry air flow, the freezing levels would be getting higher and that system was breaking up and getting warmer as it progressed eastward. I called FSS the next morning to file an IFR flight plan and update WX. Route of flight was to be VFR from O04 to hzn then IFR hzn- V32-bam-V6 ogd. I was told to expect IFR at my altitude east of bam, icing in clouds, turbulence, and light headwinds. We checked WX at various airports along route of flight and the WX was literally getting better as he was giving me the reports. The freezing level at the time was 12000-13000 ft. I figured that I would go and turn back if it got too bad. My experience with FSS WX is that it is pretty pessimistic and I could spend the night in ogd if the WX did not improve. I filed an altitude of 11000 ft (MEA). I figured that if I was below freezing level, I would not be in the forecast area of icing and thereby ok by the FARS. I was intermittent IMC east of bam, temperature was +2 degrees C, and there was no turbulence. Just east of dobys intersection, I encountered clear ice that cause a temporary loss of pitot instruments but no degradation of flight performance. I told center of my problem and asked for a vector to elko, nv. Once out of the icing, I thought it would be better to go back to bam due to better WX further west. Rest of flight was uneventful. My familiarity with route of flight, confidence in my abilities, and disregarding an far were causal.

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Original NASA ASRS Text

Title: PLT OF SMA ENCOUNTERS ICING INFLT IN MOUNTAINOUS TERRAIN. DIVERTS WITH VECTORS THEN TURNS BACK TO BETTER WX TO THE W.

Narrative: I WAS GOING TO FLY FROM O04 TO LAR TO ACCOMPANY MY MOTHER TO AN EYE OP. I HAVE MADE THIS TRIP MANY TIMES BEFORE AND FELT CONFIDENT THAT I COLD MAKE IT IN NEARLY ANY SIT. I CALLED FSS THE NIGHT BEFORE TO CHK WX AND WAS TOLD THAT THE FRONT THAT HAD PASSED THROUGH CARSON THAT DAY WOULD PRESENT SOME PROBS WITH MOUNTAIN OBSCURATION, LOW CEILINGS, AND A FREEZING LEVEL JUST ABOVE THE MEA. THEY ALSO TOLD ME TO EXPECT ICING IN CLOUDS. I WAS TOLD THAT DUE TO A STRONG DRY AIR FLOW, THE FREEZING LEVELS WOULD BE GETTING HIGHER AND THAT SYS WAS BREAKING UP AND GETTING WARMER AS IT PROGRESSED EASTWARD. I CALLED FSS THE NEXT MORNING TO FILE AN IFR FLT PLAN AND UPDATE WX. RTE OF FLT WAS TO BE VFR FROM O04 TO HZN THEN IFR HZN- V32-BAM-V6 OGD. I WAS TOLD TO EXPECT IFR AT MY ALT E OF BAM, ICING IN CLOUDS, TURB, AND LIGHT HEADWINDS. WE CHKED WX AT VARIOUS ARPTS ALONG RTE OF FLT AND THE WX WAS LITERALLY GETTING BETTER AS HE WAS GIVING ME THE RPTS. THE FREEZING LEVEL AT THE TIME WAS 12000-13000 FT. I FIGURED THAT I WOULD GO AND TURN BACK IF IT GOT TOO BAD. MY EXPERIENCE WITH FSS WX IS THAT IT IS PRETTY PESSIMISTIC AND I COULD SPEND THE NIGHT IN OGD IF THE WX DID NOT IMPROVE. I FILED AN ALT OF 11000 FT (MEA). I FIGURED THAT IF I WAS BELOW FREEZING LEVEL, I WOULD NOT BE IN THE FORECAST AREA OF ICING AND THEREBY OK BY THE FARS. I WAS INTERMITTENT IMC E OF BAM, TEMP WAS +2 DEGS C, AND THERE WAS NO TURB. JUST E OF DOBYS INTXN, I ENCOUNTERED CLR ICE THAT CAUSE A TEMPORARY LOSS OF PITOT INSTS BUT NO DEGRADATION OF FLT PERFORMANCE. I TOLD CTR OF MY PROB AND ASKED FOR A VECTOR TO ELKO, NV. ONCE OUT OF THE ICING, I THOUGHT IT WOULD BE BETTER TO GO BACK TO BAM DUE TO BETTER WX FURTHER W. REST OF FLT WAS UNEVENTFUL. MY FAMILIARITY WITH RTE OF FLT, CONFIDENCE IN MY ABILITIES, AND DISREGARDING AN FAR WERE CAUSAL.

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.