Stuff sure is changing fast...



http://www.volocopter.com/index.php/en/

Looks pretty cool, but not sure how realistic it would fit into everyday travel anytime soon. Seems like there has always been a small sector of aviation who have been obscesssd with the idea of an aerocar or something like it.

"Simply Foolproof", you can even let go of the controls and stare out the window it says . ..... hmmm , ...

Of all the "flying Uber car" concepts now being promoted at the "Uber Elevate" summit, the Volocopter seems the most legitimate to me. All the other concepts have exposed propellers or rotors at crotch height, or are far more mechanically complex than necessary. The Volocopter uses existing technology and has a lower parts count. I'll bet dollars to donuts that the FAA and the insurance lawyers will support this configuration more easily than the others.

No rotor wing pilot here, all I know is any conventional helicopter seems to take a lot of power and burn a lot fuel to perform it's magic. Once this thing is up and cruising, wouldn't a wing help in "keeping it up.," Would small rotors like these develop lift with forward motion, like a wing does, or is it a constant beating the air into submission thing?

courierguy wrote:No rotor wing pilot here, all I know is any conventional helicopter seems to take a lot of power and burn a lot fuel to perform it's magic. Once this thing is up and cruising, wouldn't a wing help in "keeping it up.," Would small rotors like these develop lift with forward motion, like a wing does, or is it a constant beating the air into submission thing?

I'm not a roto-wing pilot either, but it looks like the designers could convert the structure for the rotors into a solid disk and turn it into a fairly large surface area wing, and leave cut-outs for each rotor to generate the vertical take-off and landing airflow. Now how the 'disk' wing would effect yaw and roll, or how sensitive it would be to crosswinds I have no opinions.

Depends on the mission, just like a bushplane.

Rotors are shown to work very well within a set of known parameters. If the mission is to fly across town at 60 miles an hour, because the ground based taxi cab can only average 3 miles an hour in traffic, and VTOL is a prime requirement, then the helicopter type configuration works best.

If the mission is to fly 180 miles an hour between cities, and fuel consumption or battery weight is a prime consideration, and VTOL is STILL a big requirement, that's where the tilt-rotors and tilt-wings start to be a better choice.

I am a rotary-wing pilot as well as an engineering test pilot.

The failure mode for this aircraft and other multi-rotor/multi-engine platforms like it is "safety in numbers." There's no autorotational capability in this device's vertical propellers because they don't have collective pitch control over the blades. They're fixed-pitch props that make more/less thrust by changing rpm. Since each of them is driven by its own individual motor, you'd have to design the craft so that you have an extra (or extras) engine/prop(s) than is necessary. That way when one or more fails you have at least a controlled descent and landing capability with the remaining powered props.

Since the aircraft we're looking at has fixed pitch props, they don't account for the dissymmetry of lift that forward flight produces and will have a specific design speed because of that. There's no real way around it. Rotor blades account for this by flapping up and down in the plane of rotation, increasing/decreasing their pitch by altering the angle of the resultant relative wind with that vertical down/up motion.

Making a solid disk around the rotors wouldn't offload them like adding wings to a helicopter does. When you add wings to a helicopter, as forward speed increases and the wing contributes more lift to the aircraft, you will reduce the pitch in the rotor blades to maintain the same overall aircraft lift, which helps with retreating blade stall by decreasing the angle of attack of the retreating blade while maintaining its RPM and thus the velocity of its resultant relative wind. This device has fixed pitch propellers, so if you offloaded them with a wing, they have to reduce RPM to reduce the propeller component of lift and further exacerbate retreating propeller blade stall.

Not bashing the design, just answering the questions posed here.