Narrative:

I was on an IFR flight plan flying just above a lower broken to overcast layer. The cloud tops rose and the aircraft was subject to mixed type; moderate to heavy icing. Almost immediately; the airspeed dropped to below 80 KTS (pitot heat was on) and the stall warning horn sounded. In order to exit the icing situation; I immediately began a climb from my assigned altitude. I then informed the controller of my action but did not declare an emergency. In retrospect; I realize I should have first declared an emergency and then initiated the climb above my assigned altitude. I am unsure of the exact time or location of this event; however; I was in contact with center; the time was in the afternoon. I was asked to contact center by telephone on landing. I spoke to center and explained basically what is in this report.

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Original NASA ASRS Text

Title: A C210 pilot on an IFR flight plan encountered icing conditions and climbed from his assigned altitude without a clearance.

Narrative: I was on an IFR flight plan flying just above a lower broken to overcast layer. The cloud tops rose and the aircraft was subject to mixed type; moderate to heavy icing. Almost immediately; the airspeed dropped to below 80 KTS (pitot heat was on) and the stall warning horn sounded. In order to exit the icing situation; I immediately began a climb from my assigned altitude. I then informed the Controller of my action but did not declare an emergency. In retrospect; I realize I should have first declared an emergency and then initiated the climb above my assigned altitude. I am unsure of the exact time or location of this event; however; I was in contact with Center; the time was in the afternoon. I was asked to contact Center by telephone on landing. I spoke to Center and explained basically what is in this report.

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.