Narrative:

Skew-T showing clouds in layers up to tops of 12K; with freezing level at 11K. Clouds on satellite peter out about mid way enroute. Departed home airport with visibility 1/4 SM; 300 ovc and 48-ish degrees OAT. There were no pireps for ice and no airmet for icing. I'm planning to climb up on top. The layers are as predicted. Leaning in the climb I'm at 13 gph; 110 KIAS; climbing 500 FPM through 10K. OAT is 2C; in solid IMC. At 11.3K I note the vsi is at 100 FPM. Asi still shows 110 KIAS; but a glance to the wing shows 1/2 inch of clear ice. Simultaneously; out the window; I see patches of blue above and at our 2 o'clock. I called ATC; declared an emergency; told of the ice; increased the mixture to 17.5 gph (my best power at this altitude as was already wot/ff prop); pulled the alternate air lever twice (it's spring loaded and felt normal) and pointed toward the blue. Noted asi now showed 85 KIAS. I thought the prop may have ice too; so I did a vigorous pull/push of the blue knob; and immediately lost about 200 ft of altitude. The asi now noted 120 KIAS; so I pulled back on the yoke to 93 KIAS and got a >500 FPM climb. Within a minute and 30 seconds I'm in the ragged tops and have done a 180 on the GPS; so I leveled out above the clouds. Looking out around I see lots of blue and only a few clouds way above me. The ice is shedding; so I notify ATC the emergency is resolved and request back on course. I probably should've pulled out the poh for an 'ice' checklist but didn't. We continued north; though I had to climb to 14K a few times to stay out of the visible moisture. There were more ways I could've resolved my issue. Temperatures were all above freezing below me so I never felt in danger as long as I took evasive action. I saw no harm in taking a look-see if I could get on top with the outs available (climb to VMC; or descend to warmth); as no ice had been previously reported. I will in the future keep the wing and temp probe and windshield in my instrument scan to avoid the 'sudden' appearance of ice and therefore be able to give ATC time to give me different altitudes or vectors instead of me having to declare an emergency to be able to deal with the situation in such a rapid manner.

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Original NASA ASRS Text

Title: A BE35 pilot reported encountering ice when none was forecast. He declared an emergency because of falling airspeed. He was able to find clear air and shed the ice.

Narrative: Skew-T showing clouds in layers up to tops of 12K; with freezing level at 11K. Clouds on satellite peter out about mid way enroute. Departed home airport with visibility 1/4 SM; 300 OVC and 48-ish degrees OAT. There were no PIREPs for ice and no AIRMET for icing. I'm planning to climb up on top. The layers are as predicted. Leaning in the climb I'm at 13 GPH; 110 KIAS; climbing 500 FPM through 10K. OAT is 2C; in solid IMC. At 11.3K I note the VSI is at 100 FPM. ASI still shows 110 KIAS; but a glance to the wing shows 1/2 inch of clear ice. Simultaneously; out the window; I see patches of blue above and at our 2 o'clock. I called ATC; declared an emergency; told of the ice; increased the mixture to 17.5 GPH (my best power at this altitude as was already WOT/FF prop); pulled the alternate air lever twice (it's spring loaded and felt normal) and pointed toward the blue. Noted ASI now showed 85 KIAS. I thought the prop may have ice too; so I did a vigorous pull/push of the blue knob; and immediately lost about 200 FT of altitude. The ASI now noted 120 KIAS; so I pulled back on the yoke to 93 KIAS and got a >500 FPM climb. Within a minute and 30 seconds I'm in the ragged tops and have done a 180 on the GPS; so I leveled out above the clouds. Looking out around I see lots of blue and only a few clouds WAY above me. The ice is shedding; so I notify ATC the emergency is resolved and request back on course. I probably should've pulled out the POH for an 'Ice' checklist but didn't. We continued north; though I had to climb to 14K a few times to stay out of the visible moisture. There were more ways I could've resolved my issue. Temperatures were all above freezing below me so I never felt in danger as long as I took evasive action. I saw no harm in taking a look-see if I could get on top with the outs available (climb to VMC; or descend to warmth); as no ice had been previously reported. I will in the future keep the wing and temp probe and windshield in my instrument scan to avoid the 'sudden' appearance of ice and therefore be able to give ATC time to give me different altitudes or vectors instead of me having to declare an emergency to be able to deal with the situation in such a rapid manner.

Data retrieved from NASA's ASRS site as of April 2012 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.