Narrative:

I was on an IFR flight plan from sac to oth (north bend) at 10000 ft MSL. I used duats as my preflight briefing and checked WX again before departure using FBO WX terminals. The flight planner module of duats suggested that temperatures would be above freezing along my route. My plan was to fly from sac to rbl and make a decision to land at rbl or continue over the mountains to fjs and oth. The WX to rbl was a mix of VMC and IMC; light chop with temperatures holding around +5 degrees C. I elected to continue to fjsecond officerth based on these conditions. Prior to reaching fjs the clouds became more solid overcast. Temperatures dropped slightly to +4 degrees C but I started to pick up ice (trace at first; then the accumulation became more rapid). I noticed my airspeed start to drop and I notified ATC. I then requested a circling turn in an opening in the clouds. I was able to remain clear of clouds for multiple turns and the ice dissipated. I then continued on course with no further problems. I assume that I was flying through pockets of colder air which my 2 temperature probes were unable to register quickly enough. I realized a few things after reviewing the flts. 1) IMC and collecting ice over mountainous terrain leaves few; if any; 'outs.' I will opt for a more favorable coastal route with lower MEA's next time. 2) flying close to the freezing level in IMC can result in unexpected icing conditions. 3) notifying ATC early is a good choice.

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Original NASA ASRS Text

Title: BEECH V35 PLT ENCOUNTERS WX AND ICING WHILE ENRTE; PLT REQUESTS MULTIPLE TURNS IN A CLR POCKET TO MELT ICE AND CONTINUES WITHOUT INCIDENT.

Narrative: I WAS ON AN IFR FLT PLAN FROM SAC TO OTH (NORTH BEND) AT 10000 FT MSL. I USED DUATS AS MY PREFLT BRIEFING AND CHKED WX AGAIN BEFORE DEP USING FBO WX TERMINALS. THE FLT PLANNER MODULE OF DUATS SUGGESTED THAT TEMPS WOULD BE ABOVE FREEZING ALONG MY RTE. MY PLAN WAS TO FLY FROM SAC TO RBL AND MAKE A DECISION TO LAND AT RBL OR CONTINUE OVER THE MOUNTAINS TO FJS AND OTH. THE WX TO RBL WAS A MIX OF VMC AND IMC; LIGHT CHOP WITH TEMPS HOLDING AROUND +5 DEGS C. I ELECTED TO CONTINUE TO FJS/OTH BASED ON THESE CONDITIONS. PRIOR TO REACHING FJS THE CLOUDS BECAME MORE SOLID OVCST. TEMPS DROPPED SLIGHTLY TO +4 DEGS C BUT I STARTED TO PICK UP ICE (TRACE AT FIRST; THEN THE ACCUMULATION BECAME MORE RAPID). I NOTICED MY AIRSPD START TO DROP AND I NOTIFIED ATC. I THEN REQUESTED A CIRCLING TURN IN AN OPENING IN THE CLOUDS. I WAS ABLE TO REMAIN CLR OF CLOUDS FOR MULTIPLE TURNS AND THE ICE DISSIPATED. I THEN CONTINUED ON COURSE WITH NO FURTHER PROBS. I ASSUME THAT I WAS FLYING THROUGH POCKETS OF COLDER AIR WHICH MY 2 TEMP PROBES WERE UNABLE TO REGISTER QUICKLY ENOUGH. I REALIZED A FEW THINGS AFTER REVIEWING THE FLTS. 1) IMC AND COLLECTING ICE OVER MOUNTAINOUS TERRAIN LEAVES FEW; IF ANY; 'OUTS.' I WILL OPT FOR A MORE FAVORABLE COASTAL RTE WITH LOWER MEA'S NEXT TIME. 2) FLYING CLOSE TO THE FREEZING LEVEL IN IMC CAN RESULT IN UNEXPECTED ICING CONDITIONS. 3) NOTIFYING ATC EARLY IS A GOOD CHOICE.

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