D.C. Voltage doesn't seem to mind liquids. Keep in mind there is a brushed 12V motor submerged in gasoline on most cars and trucks.
As far as pattern dying? That is a whole thread alone. How much does a pattern airplane of WC quality cost? My estimate with a spare power system would be in the 12,000.00 US dollar range. I have see the same thing happen with pylon and soaring as well, we advance the technology and cost right up to the point of making our sport extinct.