Ben did you ever figure out the problem with loosing RPM's in a waterfall? I ask because I lost my plane yesterday due to this problem that was the first time it ever gave me any trouble and it definitely wasn't the first waterfall that day either. the engine bogged down on me when it was coming over the top of the waterfall and since I was pretty low to begin with it went splat. right before it hit the rpm's started to recover just enough to keep it from going in lawn dart style. sound at all familiar?