***Link*** :: [Bell 2009](https://www.faa.gov/about/office_org/headquarters_offices/agc/practice_areas/regulations/interpretations/Data/interps/2009/Bell-AOPA_2009_Legal_Interpretation.pdf) ***Description*** :: Interpretation on Known Icing Conditions ***Author*** :: [[FAA Office of the Chief Counsel]] #### Key Quotes * The FAA believes the term "known or observed or detected ice accretion" to be synonymous with the term "known ice" and that the agency's definition of that term is non-controversial. * "Known ice" involves the situation where ice formation is actually detected or observed. "Known icing conditions" involve instead circumstances where a reasonable pilot would expect a substantial likelihood of ice formation on the aircraft based upon all information available to that pilot. #source #legal-interpretation