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No more traffic jams at least, and also faster.
I don't want one flying over MY house, thanks.Cars on a well defined road are a big enough menace without bringing the menace onto my roof.Much more expensive for fuel , too.Possibly attractive if they were controlled automatically - but traffic density and average speeds on roads would be much better with totally automatic control, in any case. Takes the dozy human operator out of the equation.
Can there really be any doubt about the inefficiency of keeping objects suspended in the air, using reaction / wings - fixed or rotating compared with a car waiting with its handbrake on then moving when it needs to?
They even replace the oil after every flight, on military aircraft, I believe!
The whole thing about personal 'air cars' smacks too much of early Science fiction films
If you think an extra dimension would help, then let's have a lot more fly-overs and underpasses.
I just couldn't trust Joe public in the air space above my head. At least I can choose to walk on the pavement and avoid road traffic.
is not difficult we must defeat the gravity sistem
If I stand up, I am defeating gravity- that's obvious.An aeroplane is another way of doing it too - but it is neither a new idea nor practical for my rooftop. So far, all ways of lifting an air vehicle depend on 'reaction' - pushing air down or backwards to provide lift.You, also, seem to reject that as an idea (reasonably enough) so what technology did you have in mind? It would be 'nice' if it could be done but how?Without some reasonable Science or Technology it becomes Magic.
Here we go again with "Magic" i repeating my self? i am just telling one of the ways
The thought of driver-less systems is just as scary though - totally at the mercy of technology; not a very happy thought for me at all...
So you would never fly in an Airbus A320
If you put it like that George…….I can’t argue with you. It’s ALL scary LOL. - Perhaps a little of my control-freak-ishness is shining through here but despite all the logic I’m actually less comfortable if all human control is dropped. Machines/systems are overall statistically probably less error prone than humans but there is something inherently more satisfying if in the end one can blame a human rather than a machine. I don’t know…. perhaps all my warped thinking is coloured by too many silly sci-fi thrillers (the machines take over a la terminator, matrix etc) or I’m simply an even bigger control freak than I assumed so far. 
This is very true - but there is a point when the complexity and cost of a safe system would become so high that corners would (literally, perhaps) be cut. Private systems would have to be around £10k and cost tens of pounds a year to maintain. That's the scary bit.
A_s: Why are you a newbie. all of a sudden? Have you been round the clock?
Good traffic control would limit the amount of track needed.
this could be achieved simply by using flying heights from 6 inches to 10 feet above the surface (e.g. as in hovercraft), and these do not carry the same safety implication that flying 30,000 feet above the surface might do.
That would be fine; I could go for some such system but I don't think that was what the original post was about. The spirit of the post was very Buck Rogers and that is a great fun idea. However, your system doesn't give direct routes because it shares space with buildings. It is more like multi lanes, stacked vertically.
I don't think you are taking into consideration, enough, the problem of actually stopping and waiting in any mass airborne system.I have the same problem when in my boat, even. There's no such thing as a handbrake. The anchor is very much not a handbrake and is very often not possible to use and, even when you can, it involves a lot of preparation and faffing around.
A ground-based system is gloriously fail safe. Nothing else is. We make up for this in the present flying environment by making it very exclusive and very expensive.
I've heard of a lot of traffic accidents.
I'm not too sure if I'm seeing the waiting in traffic argument here...I'm envisioning something more along the lines of fixed-wing aircraft with S/VTOL capability than helicopters. Helicopters aren't really ideal for civilian travel (save in cities or areas where their landing pads can be isolated on top of skyscrapers or in the middle of no where (aka Alaska)) due to the immense amount of noise and vertical wind shear that they whip up. I really don't see the need for a pure helicopter/hover system...anything that can at least made to hold a controlled vertical descent or land in <100 feet without destroying the airframe should be fine.
Yes and no. I'm talking about using what makes the most sense where it makes the most sense -- in other words, allowing VTOL in cities/locations, and STOL in rural areas where you can grab yourself 100 feet (or less, as technology develops (namely, airfoil design) to allow for slower approach speeds) of grass, roadway, or anything of the sort. You don't need a runway. You will need a clear bit of land, yes, but that's something to factor into design of the aircraft again.
Do you make it such that the wings fold (such as found in naval aviation), the landing gear powered, and the aircraft able to operate on roads for short distances at slow speeds? Agreed, some folks might want a runway - sometimes it might be needed, but those places may also provide an economical spot for it (small urban areas, etc).
The fixed wing deal is also for maintenance -- fixed wing aircraft can survive longer than rotary winged aircraft (especially their props!).
If you are looking to provide a transportation system for 6 million city dwellers, and half a million in the surrounding rural areas, then the commercial interest will be in supplying those 6 million customers, and the other half million will merely be an add-on.
Another aspect of folding wings is that they generally would have be be fairly short, which mean a high wing loading, which means poor low speed performance (naval aircraft can only be considered as STOL by virtual of using catapults, and very, very, powerful jet engines).
Quote from: another_someone on 23/11/2007 23:46:38If you are looking to provide a transportation system for 6 million city dwellers, and half a million in the surrounding rural areas, then the commercial interest will be in supplying those 6 million customers, and the other half million will merely be an add-on.Agreed, but why would an intracity system (hence necessitating primarily VTOL aircraft manufacturing) be the focus? I'd think that you'd want something that could travel between cities or to/from them...not within them - hence necessitating something that's good for distance travel (and hence allowing a greater focus on STOVL capability than solely VTOL - you'd still need it, don't get me wrong, but it wouldn't be as if you're building a helicopter).
As for the fully managed system - to an extent. That's why you necessitate licensing for all users -- just like with cars -- and put aircraft on manual once they have adequate separate within a particular zone that includes their laid-in destination (keeping them in practice with maneuvering/landing/takeoff). Computers can't beat human judgment on some issues, agreed, so let's not put them in the pilot's seat the whole way.
I'm supposing that it'd be possible to harness the drive motor to the landing gear, though the gears probably wouldn't engage until the aircraft was on the ground (a manual control).
A "parking lot" of sorts would be helpful, but that wouldn't make these cars the personal transport that we're thinking of, right? Ground cars would still be necessary for 100% of all travel done in rural areas.
Had forgotten about aspect ratios for a moment there. However, you could build things such that the wings A) fold aft (after rotating 90 degrees - if you've ever seen a sailplane packed into its trailer, like that, save with that the wings are still attached) and fold upon themselves again (perhaps with a greater section of the wing going forward to balance things out) to keep the aircraft relatively short and able to manage a turn with only a little difficulty. They aren't meant to be ground vehicles, so we shouldn't push them to be -- at least not at the current level of technology (or that designable in the next 20 years or so (I'm assuming that's the idea here anyhow)).
But intercity air transport already exists, and while you may look at expanding it, and making it more flexible, it still more about providing a mass transit system than about applying personal transport. Personal transport is required for end to end journeys, but when you deal with hub to hub journeys, then mass transit systems are more than adequate (i.e. aircraft that carry 50+ people, rather than individuals).
The problem is that if you have a hybrid system, part manual and part computer controlled, do you not have the worst of both worlds - a computer controlled system that tries to integrate a human component.The point about a computer controlled system is that it must have total authority over their environment. If you complain that computers lack judgement, then how are they to judge what a human operator in their midst that is operating in manual mode is going to do?
And bear in mind what has already been said, that car drivers have far lower levels of training than aircraft pilots, and the idea is that if we are to have as many pilots as we presently have drivers, then we have to reduce the training requirements.
It is not the gear box that concerns me but the primary drive shaft delivering power to the wheels - might just be possible with a fixed undercarriage, but are you going to forgo retractable undercarriages?
The term 'parking lot' can have a number of interpretations - your driveway could be regarded as a parking lot, but it depends on whether it can be integrated into the system.Looking at the concept of a crane, if it was sufficiently large, you could have one crane for each block of buildings, and deliver the vehicle into any driveway within that block.
There is another scenario - detachable wings - leave the wings at the airport, and pick them up again on the way out. You could even leave the undercarriage behind, so you have a fairly conventional small car that drives up to a partial airframe, connects up with the wings and undercarriage, and flies off.
Intercity air transport does exist, but it isn't localized in the sense that you'll still need the car. What if your destination is relatively close to the city, but not enough to merit flying straight there? Why not fly there, and then rent the aircar for the rest of 0the voyage - same for flying into the major city. You still save the money, you still get to go more or less directly and fairly swiftly to your destination.
Allow me to reexplain. I'm saying that computers are fine for controlling and I'm saying that humans are sometimes better - the key is to play to their strengths. Computers don't fatigue, humans do. Humans can make rapid and highly situational judgments in wide and varied, computers cannot. Whilst in the airways, computers are a good choice - low amount of variables, easy handling (wind factors can be adjusted for), no fatigue in the system. Whilst landing/taking off/maneuvering to land (after the vehicle has exited the airway), humans are the best choice (judgment). Neither component interferes with the other unless manual control is deemed necessary by the situation (aka emergencies).
Quote from: another_someone on 24/11/2007 03:09:10And bear in mind what has already been said, that car drivers have far lower levels of training than aircraft pilots, and the idea is that if we are to have as many pilots as we presently have drivers, then we have to reduce the training requirements.As much as I dislike the idea, yeah. I'd like everyone to be trained to at least the minimum for the current sport pilot license, though. It'd be a little harder to train folks, but possible.
Quote from: another_someone on 24/11/2007 03:09:10It is not the gear box that concerns me but the primary drive shaft delivering power to the wheels - might just be possible with a fixed undercarriage, but are you going to forgo retractable undercarriages?We could...but I don't see how it'd be a problem if 'twas kept retractable, so long as everything was kept disconnected until deployment/touchdown. Sure, you'd have to get it to align each time, but that could be done.
Quote from: another_someone on 24/11/2007 03:09:10The term 'parking lot' can have a number of interpretations - your driveway could be regarded as a parking lot, but it depends on whether it can be integrated into the system.Looking at the concept of a crane, if it was sufficiently large, you could have one crane for each block of buildings, and deliver the vehicle into any driveway within that block.I'm trying to interpret what you brought up. Tell me what you're saying if I got it wrong.That'd be one heck of a crane, though. And one heck of a hard way to land! Have you ever seen the system that the British built to do that with Harriers? That's some touchy flying.I'm think that, even if you don't use it as the landing system in and of itself, it'd still be more infeasible that landing directly at home. Community airstrips would be good but, as you said, that's a lot of infrastructure. I guess it could be an "as needed" item, however, that would be brought before the township in question.
Quote from: another_someone on 24/11/2007 03:09:10There is another scenario - detachable wings - leave the wings at the airport, and pick them up again on the way out. You could even leave the undercarriage behind, so you have a fairly conventional small car that drives up to a partial airframe, connects up with the wings and undercarriage, and flies off.That'll work. Someone tried that one before - the Hall (or Convair) Aerocar if you want to look it up - though the market wasn't in for it at the time. The only thing you're running into again is having the community airport, which I've discussed above. Sounds good.
You have already suggested that some road transport will be required in the final stage of the journey (because you will not be flying directly into your driveway or rooftop). If I read you correctly, you are now suggesting a 3 level journey - road transport to the point of local flight, then from local flight to intercity flight. This sounds like it will be adding complexity without much benefit.
OK, let's take this all in context.If you're flying into an extremely rural area (think New Hampshire rural with trees everywhere), then yes, you'd have to find an open spot to land in...such as a roadway or an area cleared and hardened for the purpose. Then we'll get into the fact that you still need to drive home, since 'tis impossible to fly there anyhow (or get craned there). Makes sense, no?However, if you're flying into a less rural/somewhat urban area, you probably could land AT home/on a road about fifty meters from your house, depending on what variety of aircar you bought/is available (STOVL).If you're flying intercity, the best bet would be to take said existent transport to within the city and then airtaxi to your destination simply because of economy -- mass transit.
You can't have one system for everything -- it'll have to change depending on the area, which is also what I'm arguing for the navigation systems. Either you or someone else on here stated something before to the effect that regardless of computer precision in flight, it cannot judge things such as the condition of the landing field, etc. What if the engine fails and you need to land out? A human is going to have to do that (unless you can guarantee an airfield with an MLS installed within gliding distance of every airway...which you could do in many places (if it gets mandated by the FAA for all FOBs at some point) - but NOT all, especially in wooded/mountainous areas...in which case your only chance for survival lays with the pilot).
Training...do you have a copy of the FARs (CFRs, whatever you want to call 'em) around? Look in part 61.56a -aka flight reviews (annually, though, not biennials). That's the key. I'm not saying 'tis a cure-all, but it'll knock out bad habits that often lead to accidents/incidents (by the way -- something that you might enjoy: CFR 61.153c, eligibility requirements for an ATP rating: "be of good moral character." That appears for no other rating that I've yet looked at.).Besides this, the absolute minimum training requirement for the sport pilot license is 30 hours of instruction -- that's not that much below what's required for a private license (40 hrs in airplanes)! Looking at the PTS for sport pilot, I'm thinking that 'tis possible to get folks adequately trained. The NTSB hasn't released accident data for sport pilots (nothing since 2002, or so I've found, and sport licenses are a fairly recent development), and there isn't much discussion online about it (AOPA, Flying magazine, Google, etc). Where are you getting your accident data from?Who's going to pay? Those who wish to use the system. Do you have to pay for a driver's license? No, you don't HAVE to...but you do for the convenience. This'll cost more, true, but for a greater convenience. Capitalism! Not that I'm a fan of the system, but that's what we live in (right now).
Either have separable wings (which I can vouch for as being safe...as can every single glider pilot in the world who connects everything properly) or foldup. My vote's with the detachable option. Very much with the detachable option.So, let's see what we have here:Short range fiberglass/carbon fiber composite electrically powered car that can attach to a set of wings/tail assembly as well as a powerplant (which recharges the car batteries when in operation). Aircar is then STOVL capable (or VTOL, depending on starting location (air taxi (I'm going to revive the VTOL concept for them, since they're short range only))), is automatically flown to an airway if need be (determined from a preprogrammed destination) and thereby to the destination area where it is landed, unless the area lacks a MLS in which case the PIC will then assume control and land the aircraft (as would also be done in the event of an emergency outside of an MLS). Car will detach or aircraft will be driven to park (depending on landing location (home or local airfield).How abouts that?