RE: GP DR1 Triplane flapperons or not.
Not -- flapperons will increase the effective AOA at the wingtips & increase the liklihood of a tip-stall. The DR-1 will land slowly enough that there will be no usefull gain, but there will be an increase in risk. Part of the landing probs with the DR-1 is rudder blanking by the wings -- flapperons can't help there & may make things worse.