I'm not sure which profile the old rudders were, but they were built about 2000, so must be the NACA section. The Alu sock is a [censored] design also, heaps of play in the blade/stock fitting.

I think the M20 blades are an NFI section (No [censored] Idea!!) they look a lot like the T blades but with less chord and a slightly less prominent hollow in the rear 1/3 of the blade.


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