Designing Griffin, a quad-lip-wing VTOL aircraft

 I started designing a quad-lip-wing aircraft, named Griffin a while ago. I was opposed building multi-rotors since there is a efficiency penalty due to decrease in Reynolds number, but this is an easy configuration to control and build. Moreover, since the rotors tilt, there is an option to retain all hover control even if any rotors fail by transforming into a tricopter configuration.