In a weird request, FAA issued a request for public comment on known icing, contrary to what the industry was expecting. The Regional Air Cargo Carriers Association, along with other user groups have been trying to overturn an interpretation on icing issued by the Eastern Region last summer that would have grounded much of the fleet not equipped for flight in those conditions. It looks as if the FAA, in not wanting to directly overturn the Eastern Region, is going back to square one and asking the industry to answer the original question: How’s a pilot to know what is known icing for enforcement actions? Related Story
Rather than overturning, the agency essentially wants the industry to tell it what known icing is in terms of enforcement. In its response to a petition by aviation users, the FAA basically reiterated current rules and regulations, asking operators to weigh in on the subject. The letter of interpretation, dated June 6, 2006, responded to a request by Robert Miller that the FAA clarify when ``known ice'' exists for purposes of enforcement action. Last summer, FAA's Eastern Region Counsel effectively gave operators of aircraft not equipped for flight into known icing two options during winter weather: Either ground the aircraft or risk being violated. That interpretation said conditions of instrument meteorological conditions (IMC) or high humidity at or below freezing temperatures constituted "known icing." In response, RACCA, the Aircraft Owners and Pilots Association and other organizations took exception.
To its credit, said RACCA, the FAA's Flight Standards Division recognized the problems such an interpretation might create and convened a meeting with FAA Chief Counsel. The request for comment was published in the Federal Register on April 3. (Federal Register Online via GPO Access wais.access.gpo.gov DOCID:fr03ap07-103) Comments are due May 3.
In its draft response to a request by the Aircraft Owners and Pilots Association to rescind the Eastern Region interpretation, FAA cited NTSB’s decision making, saying it reflects the common understanding that the formation of structural ice requires two elements: visible moisture and an aircraft surface temperature at or below zero degrees Celsius. The NTSB holds that known icing conditions exist when a pilot knows, or reasonably should know, of weather reports in which icing conditions are reported or forecast. However, FAA also noted that even in the presence of these elements, there are many variables that influence whether ice will actually form on and adhere to an aircraft. The size of the water droplets, the shape of the airfoil, or the speed of the aircraft, among other factors, can make a critical difference in the initiation and growth of structural ice.