Narrative:

10 mins prior to departure, I received an abbreviated briefing focusing on flight precautions along our route of flight, luk to gai. The briefer said there were two airmets of concern, one for icing above 5000 ft for up to 30 mi east of luk, and the other for moderate turbulence below 8000 ft as we got closer to gai. I had filed for 11000 ft upon arrival an hour earlier based on my experience during the trip to luk along the same route. The briefer also provided me with a number of PIREPS for icing conditions in the luk area. All were for altitudes above 5000 ft. Our plan was to ask for 4000 ft during the climb, considering the PIREPS. Seeing that the clouds were higher, we asked for, and were cleared to, 5000 ft. This altitude kept us clear of any clouds within sight. About 20-30 mins into the flight I saw a lone, small, weird looking cloud that extended below the layer at 6000 ft down to about 4000 ft. Outside air temperature was around -3 degrees C. Immediately upon entering the cloud the windshield was pelted with what appeared to be rain, freezing rain, and snow mix. I immediately requested a descent to 4000 ft and was so cleared. This 'cloud,' upon reflection, was probably virga. I began the descent and noticed no change in the altimeter reading. The ai showed about a 4 bar descent angle. The passenger, also an instrument rated pilot, reported the condition to the controller and opened the alternate static source. After what was probably no more than 1 1/2 mins (although it felt longer) we were in the clear. Within another min, the static source was clear and all instruments were functioning normally. I believe the choice to depart was correct, safe, and within the spirit of far 91.527, operating in icing conditions. The problem was not recognizing the true nature of the cloud. Also, given that the cloud was small enough to fly around and remain basically on course, the right decision would have been to fly around it and not through it. My appreciation to the controller for her quick clearance to lower.

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Original NASA ASRS Text

Title: PLT OF A C210 ENTERED FREEZING PRECIPITATION (VIRGA) HANGING DOWN UNDER AN OVCST WHICH IMMEDIATELY CAUSED THE STATIC PORT TO FREEZE OVER AND THE ALTIMETER CHANGE DURING DSCNT OUT OF THE PRECIPITATION. INSTS AFFECTED BY THE ICE CAME BACK TO NORMAL OP AFTER ALTERNATE STATIC SOURCE WAS APPLIED AND THE SUBSEQUENT DSCNT OUT OF THE ICY PRECIPITATION.

Narrative: 10 MINS PRIOR TO DEP, I RECEIVED AN ABBREVIATED BRIEFING FOCUSING ON FLT PRECAUTIONS ALONG OUR RTE OF FLT, LUK TO GAI. THE BRIEFER SAID THERE WERE TWO AIRMETS OF CONCERN, ONE FOR ICING ABOVE 5000 FT FOR UP TO 30 MI E OF LUK, AND THE OTHER FOR MODERATE TURB BELOW 8000 FT AS WE GOT CLOSER TO GAI. I HAD FILED FOR 11000 FT UPON ARR AN HR EARLIER BASED ON MY EXPERIENCE DURING THE TRIP TO LUK ALONG THE SAME RTE. THE BRIEFER ALSO PROVIDED ME WITH A NUMBER OF PIREPS FOR ICING CONDITIONS IN THE LUK AREA. ALL WERE FOR ALTS ABOVE 5000 FT. OUR PLAN WAS TO ASK FOR 4000 FT DURING THE CLB, CONSIDERING THE PIREPS. SEEING THAT THE CLOUDS WERE HIGHER, WE ASKED FOR, AND WERE CLRED TO, 5000 FT. THIS ALT KEPT US CLR OF ANY CLOUDS WITHIN SIGHT. ABOUT 20-30 MINS INTO THE FLT I SAW A LONE, SMALL, WEIRD LOOKING CLOUD THAT EXTENDED BELOW THE LAYER AT 6000 FT DOWN TO ABOUT 4000 FT. OUTSIDE AIR TEMP WAS AROUND -3 DEGS C. IMMEDIATELY UPON ENTERING THE CLOUD THE WINDSHIELD WAS PELTED WITH WHAT APPEARED TO BE RAIN, FREEZING RAIN, AND SNOW MIX. I IMMEDIATELY REQUESTED A DSCNT TO 4000 FT AND WAS SO CLRED. THIS 'CLOUD,' UPON REFLECTION, WAS PROBABLY VIRGA. I BEGAN THE DSCNT AND NOTICED NO CHANGE IN THE ALTIMETER READING. THE AI SHOWED ABOUT A 4 BAR DSCNT ANGLE. THE PAX, ALSO AN INST RATED PLT, RPTED THE CONDITION TO THE CTLR AND OPENED THE ALTERNATE STATIC SOURCE. AFTER WHAT WAS PROBABLY NO MORE THAN 1 1/2 MINS (ALTHOUGH IT FELT LONGER) WE WERE IN THE CLR. WITHIN ANOTHER MIN, THE STATIC SOURCE WAS CLR AND ALL INSTS WERE FUNCTIONING NORMALLY. I BELIEVE THE CHOICE TO DEPART WAS CORRECT, SAFE, AND WITHIN THE SPIRIT OF FAR 91.527, OPERATING IN ICING CONDITIONS. THE PROB WAS NOT RECOGNIZING THE TRUE NATURE OF THE CLOUD. ALSO, GIVEN THAT THE CLOUD WAS SMALL ENOUGH TO FLY AROUND AND REMAIN BASICALLY ON COURSE, THE RIGHT DECISION WOULD HAVE BEEN TO FLY AROUND IT AND NOT THROUGH IT. MY APPRECIATION TO THE CTLR FOR HER QUICK CLRNC TO LOWER.

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.