I think most of the time it is used simply for exactly what you said. I know some people speculated initially that it was used for downline breaking, but that isn't how Chip and others are using it. I flew Chip's passport last year with it and the rudder authority was phenomenal. Knife edge flight had very little nose high attitude. The performance is spectacular, especially given the size of the 9650 servos in the tail that are doing the work. I have also flown Passports without the split rudder and they flew excellent as well. Rudder authority was definitely more than enough, but I think the one with the split rudder may have had just a bit more.

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