Aeronautical Engineering

[Barquentine]

Are there any aeronautical engineers out there? Have you seen the Flyability Elios drone? I would love to scale up one of those and strap it to my back then up, up and away!

Except, a friend who is learning to fly a helicopter said it would not work. She has to study theory as part of her flying lessons but from the small amount she has done she said it would not be technically feasible but didn't explain in detail.

Would anyone happen to know why a large buckyball type frame with the rotor-blades safely behind the frame's struts could not have a harness or seat attached to lift a man...or woman?

[Buenchico]

I'm not an aeronautical engineer but I did teach physics and I can see a fundamental flaw in your proposal.

Directly scaling up from a small size to a large size with anything that flies usually won't work. For example, if you could create an eagle that was 10 times as big as the ones found in nature, it wouldn't be able to fly. That's because an eagle's ability to achieve lift is, just like an aircraft's, largely dependent upon the surface area of its wings. If you increase the eagle's linear dimensions by 10, you'll increase the surface area of its wings by 10 squared = 100. However you'll increase its volume (and consequently is mass) by 10 cubed = 1000. So you'd end up with a mega-eagle weighing 1000 times what a natural one does but with only 100 times the lift available to its wings, meaning that there would insufficient lift available to get it off the ground.

Similar considerations apply to your own plans. As you scale up the size of the drone, the weight will increase faster than the surface area of its blades does, so that it can no longer fly. (In practice a small amount of scaling up might be possible by using more powerful motors to rotate the blades faster, providing some extra lift that way, but what you're proposing simply isn't going to work).

[Atheist]

Wouldn't a scaled up drone be a helicopter?

[Barquentine]

Thanks Buenchico, that all makes sense and I assumed it might be something to do with lift/weight ratio. I'm wondering if if there would be a way to use four sets of double rotor-blades somehow all decoupled from the frame the way the Flyability people have done. I've seen one-man drones on YouTube but sitting so close to those exposed rotor blades spinning rattles even my minimal health & safety concerns. I still think there might be a way to adapt the Elios' unique design to let me one day strap something to my back and escape all the traffic jams! If only I'd studied harder for my physics O-level!!