Various personal VTOL has been proposed for decades but unfortunatelly, never be successful. The biggest problem is safety concern against power fail. When power is failed, VTOL will immediately fall like a stone. Imagine you are diving from concrete wall on a bicycle with some 100lbs of stuff strapped on your back. Even from altitude only 10ft, it will hurt you pretty much.
Airplane can glide (unless wing came off). Helicoper can auto-rotate (give spin to roter like windmill, reducing decent rate by drag). No such power-failure safe landing method is built in with thurst-lift VTOL. Some designer tried to give redundency with multiple engines, but this option will reduce already scarce payload capability.
We'll need near-100% reliable power source, or some genious method of soft landing on power fail. I think if parachute can be launched and blossomed with exprosive (or compressed gas) so it can be deployd from low altitude...
Drones are, in essence, flying autonomous vehicles. Pros and cons surrounding drones today might well foreshadow the debate over the development of self-driving cars. In the context of a strongly regulated aviation industry, "self-flying" drones pose a fresh challenge. How safe is it to fly drones in different environments? Should drones be required for visual line of sight – as are piloted airplanes? Join EE Times' Junko Yoshida as she moderates a panel of drone experts.