Gas power is a very good option I do see drones that are big enough to carry a human on Utube but like everything video doesn't lie, ha ha. I would like to stick with electric motors with a reduction gear for torque. But I need to figure what motors first and I would like them one size over what I would need. Looking at a 4 to 8 propeller setup can be a pull push option with retractable booms i.e. they fold in next to the pod to fit in my Van. With the motors flight duration should be about a 45 minute.