The NutBall is another RC/Groups design that I built from 8 mm thick EPP Foam sheet.  My NutBall is 24 inches in diameter, and has 18 degree dihedral in each wingtip.  It is controlled by rudder and elevator using a Futaba 6106 FASST 2.4 GHz park flyer receiver.  Total weight is 10.4 ounces with battery.  It is powered by a G Force outrunner electric motor weighing 29 grams.  It uses an 850 mAh 2S LiPo battery to turn an 8X4 Propeller. Like most flying wings, the NutBall needs a bit of reflex adjustment  ( up elevator trim ) to maintain a positive angle of attack.  I've flown it in a Soccer Barn, and it demands coordination between throttle and elevator.  A bit too much of both together, and it will swap ends. If things are just right you can make a slow pass at high angle of attack.  In this it resembles the post WWII experimental U.S. Navy plane , the  Vought V-173 "Flying Pancake".