I have some experience in different levels of icing in TB20 and DA42 both with full airframe and propeller(s) TKS. Almost every time the icing was worse than forecasted. I’ve found severe icing at -24, I’ve found it when not forecasted at all. TKS on, alternate air on and closely watching accumulation, monitoring the engines, monitoring TKS pumps and planning the escape route are the actions that I immediately perform and it works. What I learned few days ago is that there could be huge difference between turning TKS on prior and after hitting icing conditions. In pretty light conditions I got ice layer over leading edges which TKS fluid wasn’t able to remove i.e. it removed it just on few spots, unnecessarily spilling fluid through these spots at max rate while at the rest of the wing nothing was happening until I descended to a bit higher temperatures. On all previous encounters that haven’t been a problem.
It is comforting that my TKS-fellows also had their sweat moments.
Boots are nice and good but with experience I am really not willing to fly (up or down) through more than 3000 ft of icing layer with my “FIKI” setup.
3000 ft is 3 minutes on the way up and 2 on the way down and this is all I am prepared to stay in “pick up ice mode”.
Consequence: staying home this week end. There is a 10’000 ft icing layer – no go
