Maybe you dont get rain ice in Aus but it certainly exists and can be the most severe icing you will get, normally rain ice will be not far below freezing so will be a form of clear ice. Hoar frost is also a real form of airframe icing but is formed by sublimation. For the OP, the colder the moisture the more freezes on impact which forms ice with lots of air in it and is cloudy and brittle and breaks off easily, this is Rime ice and will be from small water droplets as larger ones will not normally stay liquid at colder temperatures. If it is not so cold then only a little freezes on impact, the rest then runs back freezing as it goes and forming a clear solid layer of ice that is hard to remove, this is clear ice.
Last edited by foxmoth; 25th Aug 2016 at 08:30.
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