BMatthews

Oh yes, I've never seen or heard of a plank style flying without a vertical fin or rearward placed tip fins. And the wing on a plank style model generally uses very little if any washout since washout would act like up elevator in the plank wing's case. Lift distribution is elliptical in a way similar to conventional wings. Typical swept flying wings that use the washout to achieve pitch stability actually drive the tip airfoils into very low or even negative lift coefficients so the lift distribution looks like that bell curve you mentioned rather than a steep ended elliptical shape. However since they are either not swept at all or only marginally swept due to leading edge tapering the plank style relies on highly reflexed positive Cmo type airfoils like the Eppler 186.