NTSB Issues Deicing Safety Alert

Looks like “Captain Obvious” material. Anyone that has ever read “Fate is the Hunter” by noted author Ernest Gann realizes that icing has been a problem since the early days of air mail–about the last 100 years.

Quote: “However, the FAA’s recent tests show that modern deicing boots, from aircraft manufactured after 1960, are not prone to ice bridging.” REALLY? I’ve been flying IFR in Minnesota for the past 58 years–flying freight in singles and twins, flying corporate in light twins to jets–28,000 hours. Yes, I’ll tell you that “engaging the boots when icing begins” WILL eventually lead to “ice bridging”–as boots work by expanding and cracking off the accumulated ice. If you don’t allow an accumulation to build first, you can’t crack it off–and premature operation of the boots will allow the ice to “Bridge” over the expanded boot–leaving NO WAY TO CRACK IT OFF.

The best way to “fly ice” is to go where the icing ISN’T–stay in warmer air, or climb quickly to an altitude where there isn’t enough water in the clouds to accumulate ice in the first place.

I have over 12,000 hours in King Airs and other turboprops–they are not immune to ice (even with “known icing”) but the ability to climb and descend rapidly through icing layers keeps icing accumulation and boot use to a minimum, as there is not enough accumulation to crack it off. Increased indicated airspeed also helps–it keeps the “stagnation point” on the airfield in a fairly narrow band–any accumulation is easier to crack off.

Note: Some aircraft carry ice better than others. The fat wing on an Aztec, for example, tends to accumulate ice in a fairly narrow band on the leading edge–somewhat mitigating the effects of a buildup–BUT–look at the tail leading edge surfaces on the same airplane–they are thinner, and accumulate ice faster.

The best way to handle ice is to simply MINIMIZE EXPOSURE to the altitudes and conditions where it occurs. Ask for an expedited climb or descent–and always have a “plan B” to escape icing conditions. In years of flying people and freight in Minnesota (where icing occurs at least 6 months out of the year), I’ve rarely had to cancel a flight, as long as I’ve had a diversion option–but I won’t launch UNLESS I HAVE A PLAN FOR ESCAPING ICING CONDITIONS.

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