Russian patent RU2502641:
http://www.ntpo.com/izobreteniya-rossiyskoy-federacii/letayuschie-apparaty/38911-bespilotnyy-dvuhfyuzelyazhnyy-vertolet-samolet.html
lllll As of 2019 I have transitioned; My name is now Rei. Please don't deadname or misgender me, thank you. <3 lllll