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more effective methods for dealing with ice and snow, both before and during flight. We now have many types of deicing and anti-icing fluids, and equipment for in-flight anti-icing and deicing of critical components. We also have more respect for meteorological conditions conducive to dangerous icing: super-cooled water droplets, for example.We have also changed the procedure for when to deploy deice boots, and the conditions and temperatures at which we engage electrical and bleed air deicing systems – some of them now fully automated. We deice or anti-ice induction systems, engine inlets and IGV’s (inlet guide vanes), static ports, stall and AOA (angle-of-attack) vanes, pitot tubes, fuel vents, windshields, propellers and the leading edges of wings and tails. On the MD-80, we also have permanent “heater blankets” on the most inboard-top section of the wings, forward of the engines. This is to prevent cold soaked fuel tanks from creating their own ice between flights during periods of high humidity. Components not protected from ice must be certified as “self-shedding” – items such as communication and navigation antennas.Known IceThe operating manual for your aircraft contains a list of required components, limitations and operating procedures for your known-ice certification; verify that all components are functional. Check that the heated devices, including individual prop blades, all work. Some components may not be heated on the ground, such as R AT (ram air temperature) or CADC probes—heating them on the ground can cause inaccuracies in take-off thrust computing systems. One often-forgotten piece of required known-ice equipment is inspection lighting, such as for the leading edge of at least one wing. And don’t forget what the FAA says about taking off with any type of contamination adheringto your airframe, engines or flight controls—Thou Shalt Not.Ground equipment has made increases in function and efficiency. Many airports now have deicing equipment installed at dedicated areas—including procedures to protect the environment from the estimated 25 million gallons of fluids used each year. FBO’s at large airports will have deice and anti- ice fluids for GA; make sure you know which ones meet the “shear” requirements for use on your aircraft. Shear-speed is the speed during takeoff at which the relative wind is sufficient to blow the fluids, and any contaminants held in suspension, away from the aircraft. A specified amount of the fluids must blow off the airplane by rotation speed. Thin, or low-viscosity deice fluids (Type I and III for example) blow off at a relatively slow speed—less than 100 kts. Thick or high viscosity anti-ice fluids (Type II and IV) need higher speeds – usually above 120 kts.In the Duke, it’s often a challenge to get from the hangar to rotation speed if it’s snowing. The “holdover time” for Type I fluid is not very long. Holdover time is the amount of time during which deice or anti-ice fluid will provide suitable protection from contaminants. Holdover time for deice fluid is relatively short, and for anti-ice fluid it’s longer; both types are affected by the intensity of precipitation as well as OAT.Tail-Plane StallsYour operating manual should also contain procedures and techniques to recognize and deal with deicing related failures. Complete and partial failure of boots or bleed- air, IGV or single propeller blade heat malfunctions, and unreliable airspeed, for example. Recognition and recovery from tail-plane stalls (caused by ice accumulation after the failure of your elevator/stabilizer deicing system) is sometimes overlooked. The procedure is typically the opposite from that of a wing stall.Another topic for review is the effect of runway contamination on V1, minimum runway requirements and the interpretation of Mμ readings: the coefficient of friction or the braking coefficient.California Dreamin’The flight to Tampa on that cold December morning was an introduction to the time-machine effect and weather-altering capabilities of flying. Our airplanes can take us to any type of weather we desire, usually in the same day. When all the leaves are brown and the sky is grey, flying can quickly get you out of the cold and into an ocean-side beach chair, or from your beach chair to a snowy chair-lift. If you haven’t flown in snow and ice lately, review the topics of this article – maybe skipping the fortune cookies and fortune teller parts.The sound of cicadas on hot, no- wind days and crickets during the cool nights has come to an end for the year. And now that we’ve seen the forecast from the Farmers’ Almanac, we can approach winter with giddy anticipation of record cold and snow; well, some of us are a little bit giddy. Even though cold weather flying is a challenge, I look forward to a heap of snow; it will give me a chance to use that roof-rake I bought ten yearsago. And to skip school. T&T •Kevin Dingman has been flying for 40 years. He’s an ATP typed in the B737 and DC9 with 19,000 hours. A retired Air Force Major, he flew the F-16 then performed as a USAF Civil Air Patrol Liaison Offi- cer. He flies volunteer missions for the Christian organization Wings of Mercy, is employed by a major airline, and owns and operates a Beechcraft Duke. Contact Kevin at Dinger10d@gmail.com.OCTOBER 2013 TWIN & TURBINE • 19