Other areas have potential for big weight variations--engines and props. eg a BD4 can be flown as a 2 seater with a 100 HP C - 0200 & a wooden prop at one end of the scale or a 4 seater with a 300 HP C- IO520 with a constant speed metal prop at the other end. A very large mt wt variation I would think. does anyone know the engine & prop combination of the aircraft in question ?