Have a rotorcraft that has two or more horizontal rotors? Then you're in the right place! Bicopters, Tricopters, Quadcopters, Pentacopters, Hexacopters, ...from Google Alert - quadcopter http://j.mp/2B1rU8jvia Tommy Gerlado
https://www.tommygerlado.com/2019/01/showing-my-87-year-old-mom-how.html