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Nice in theory. Now we will see crashes in the third dimension (height)!

In reality, the only way these vehicles can travel safely is to remove human error and make the flight totally automated with a central "flight controller". Airplane pilots are well trained to fly, but who is training car drivers on our roads? Most car drivers leaned though a friend, schoolmate or a family member (I did), and most of the time it is badly done.

As I said before, if we can't train two-dimensional vehicle drivers correctly, how can we expect to be trained for three-dimensional flight? The only option is to remove the human and let the vehicle fly itself.
 

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Call me a pessimist, but with all the problems the Osprey has had over the years I have a hard time believing a private/profitable company can pull something like this off.
 

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Nice in theory. Now we will see crashes in the third dimension (height)!

In reality, the only way these vehicles can travel safely is to remove human error and make the flight totally automated with a central "flight controller". Airplane pilots are well trained to fly, but who is training car drivers on our roads? Most car drivers leaned though a friend, schoolmate or a family member (I did), and most of the time it is badly done.

As I said before, if we can't train two-dimensional vehicle drivers correctly, how can we expect to be trained for three-dimensional flight? The only option is to remove the human and let the vehicle fly itself.
I read an article about the TF-X this morning, and you'll be happy to know, that it does have a fully automated flight control system. You can input your destination and it will to all the work for you. It is also supposed to have the ability to call the authorities if it deems you to be operating in an unsafe manor.
 

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The phone ate my earlier quick reply, so I've had more time to look at it and play with numbers. This isn't completely impossible, but it's very unlikely, and more unlikely to be cost-effective.

They weren't kidding about the megawatt of power - 1300 horsepower. Using basic disc loading math and rough numbers assuming 8 foot diameter propellers (trying to scale from the video, I think that's the largest it could be,) I came up with ~500 horsepower for an OGE hover at sea level standard, with an optimistic 3200 pounds.

For comparison, a 3200 pound Jet Ranger needs ~160 horsepower in the same environment, because of the 33 foot diameter rotor (smaller discs are less efficient - see this discussion about disc loading: http://en.wikipedia.org/wiki/Disk_loading)

The other thing is that small discs have to move the air very quickly - over 80 feet per second if I did my math right. This 55 mph breeze will be detrimental to everything around the aircraft. This is faster than any service aircraft - 10% more than a max overload V-22, and nearly 30% higher downwash than a normal gross weight V-22.

They seem to gloss over stability and control - they leave you with the impression that these are just folding propellers - when in fact you need swashplates and links to generate the differential lift to control the car with two rotors. The technology is well established, but it's inherently complex, and generally requires some maintenance (and a failure of any of these elements in flight will cause a crash.)

The center of gravity in the longitudinal direction also has to be controlled tightly in this layout - it has to be within a foot or so of the center of the rotor discs at this scale to be controllable at all - and should be much closer to the center than that. For a conventional aircraft design, the center of gravity should be just slightly forward of the quarter chord line of the wing surface, again for stability and control. This one is so far forward from the wing it'll require massive downthrust from the rear engine to keep it flying straight - which is not only very inefficient, but also means an engine failure will cause an immediate nose down response, likely unrecoverable (or else the CG is located well at in the rotor discs, causing a less efficient hover and limiting the car's ability to pitch nose down in vertical flight - the one direction it always needs to go to transition to forward flight.)

In short, there are a bunch of reasons your flying car never materialized. It's within our technical capability, but it'd cost a fortune to build, eat a lot of fuel, and require a lot of maintenance.
 

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Pipe dreams, still I wish them the best. I thought version one should have been flying by now. Flying cars? If the Volt can be built, why not?
 

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Call me a pessimist, but with all the problems the Osprey has had over the years I have a hard time believing a private/profitable company can pull something like this off.
Ditto that...:(
 
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