I note that they don’t talk about using this to replace ordinary passenger vehicles, but do talk about using it to replace things like air ambulances, which make sense, since there’s simply no way the FAA would ever allow the average slob to have a flying car, but a flying car would be able to land in more confined spaces than a helicopter could.
Depends. Would you let an evil German scientist diddle your weiner for one?
One problem is that ducted rotors will tend to be of short span, which implies a low aspect ratio. Such vehicles will thus not be fuel-efficient, and will likely be quite noisy (probably worse than current helicopters).
It also has the passengers in the same plane as the rotor (for the C Model, anyway). Lose a rotor blade and it’s going to be a bad day for someone. There’s also no way you’re going to autorotate this thing down, and no conceivable recovery mode with engine or rotor failure. The ducting might attenuate the noise somewhat, but given how large they are, despite the presence of vectoring slats, I don’t think they’re going to offer you any performance improvement.
The Piasecki VZ-8 Flying Jeep (which the references), like the VZ-9 Aerocar and other large fan ducted or Coandă effect VTOL experimental craft, all required the backpressure from ground effect for both sufficent power to maintain lift and stability; raising more than a few feet demanded a severe increase in power and caused massive stability problems making it statically unstable in “flight” ; even with their ducting and active feedback controls I doubt you could make this design marginally controllable. Dynamic stability is even worse; in flight, you’re going to have problems with the c.g. location being further back than the c.p., making it unstable; even assuming controls algorithms to deal with this you need to have control surfaces and/or vectored thrust to balance out destabilizing forces.
But this thing is clearly vaporware; it looks like it was “designed” in Rhino3D or some other cheap package and given some rudementary “stats” with little or no engineering basis whatsoever.
Stranger
Well, I’m still wondering where my clones are. I’m moving towards retirement and they were supposed to be bringing home the bacon by now, those souless bastards.
To be fair, the same is true for a helicopter.
Good points. Indeed, except when close to the ground, even a minor loss of power could be fatal.
Not to the passengers, though; a main rotor blade failure (rare, but it does occur) will fly outward tangentially, and the odds of a rear rotor blade being released toward the fuselage (and not being stopped by the transmission or engine) are pretty slight. With this thing–and the turbofans rotating at much higher velocities–the likelyhood of injury or death is significant, and no conceivable amount of protection is going to prevent it.
A single large ducted rotor piped to outboard nozzles is probably the best way to make a flying car; better yet, dual rotors which can provide redundancy (with the rotors having an overthrottle capability in case of single rotor failure to permit landing or at least retard impact speed). But this is all going to require commodity-scale high speed turbine manufacture, massive improvements in efficiency, some kind of high energy density fuel or fuel cell technology, and a degree of reliability and/or redundancy seeing in the commerical aviation industry without the kind of training and inspection requirements to be viable as anything but an expensive special purpose vehicle. Those aren’t minor niggling details; they’re major engineering hurdles, and I see no indication that Urban Aeronautics has addressed any of these. They’ve made some nice pictures, but that’s about it.
Stranger
At the very LEAST, we should all be wearing a lot more silver lamé.