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> The optimal altitude flown would be lower for shorter trips Where does the column of flying cars go? Do they expand vertically or horizontally as traffic i

by iaw 10y ago

> The optimal altitude flown would be lower for shorter trips Where does the column of flying cars go? Do they expand vertically or horizontally as traffic increases? In the underpopulated area's of the US where 10% of the population lives this is a feasible mode of transit, what about the 90% that actually have traffic? If the cars broaden vertically it's a safety risk, if the cars broaden horizontally it's a violation of property rights (and a different safety risk), if the cars don't broaden it rapidly becomes inefficient and dangerous. Also, with the advent of KERS and other regenerative systems cars will be able to recapture the bulk of energy consumed for elevation changes. To my knowledge there's no such effective system for planes. So the efficiency on cars is still higher than air vehicles.

jessriedel 10y ago
> If the cars broaden vertically it's a safety risk, That's the evidence you're giving to dismiss the ability of flying cars to distribute over multiple altitude? Once we've accepted the hypothetical that technology allows for a single car to fly from A to B safely (which is almost certainly automated), it seems clear that having cars move at different altitude will be trivially possible. > Also, with the advent of KERS and other regenerative systems cars will be able to recapture the bulk of energy consumed for elevation changes. To my knowledge there's no such effective system for planes. So the efficiency on cars is still higher than air vehicles. No one is disputing that regular cars are more efficient than flying cars. But trucks are less efficient than container ships, and we still use the former when the latter is impossible or too slow. You said "Flying is not a valid commute solution and never will be because of physics", and this just isn't true.
- inlineint 10y ago
  > Once we've accepted the hypothetical that technology allows for a single car to fly from A to B safely (which is almost certainly automated), it seems clear that having cars move at different altitude will be trivially possible. In real world we can't accept this because there are always unpredictable factors, we can only say that probability of a safe flight in a single car is say 99.999%. Then if there are 20 cars one right above another, then probability that none of them crash is only 99.98%, and it could damage all cars below it, so the resulting probability of safe flight in a car reduces to something of order 99.99% instead of 99.999% for a single car. And 99.99% is really not safe enough for everyday flying during many years.
  - jessriedel 10y ago
    Avoiding a car that crashes in the lane next to you is a lot harder than avoiding a car that falls 100 feet from above. Yet we have multi-lane highways.
    - iaw 10y ago
      That's an asinine statement if I've ever read one. I've been present for 2 highways collisions, avoiding them is super easy. Which is why full lane closures and multi-car pile-ups are as infrequent as they are relative to the frequency of two car accidents. A vehicle that falls from 100 feet above will be accelerating unlike vehicles in an accident on a highway which will rapidly decelerate. Furthermore, you now have multiple vehicles taking evasive action based on dynamic predictions that cannot incorporate a collision. The second that one car hits another you're going to lose a chunk of your column from pachinko like bouncing. Now, instead of a small mechanical failure you can have drastic loss of life because all of the occupants plummeted to their death. Do you work for Uber?
      - tomcam 10y ago
        Upvoted because you're right, but not sure why you felt it necessary to be so hostile
        iaw 10y ago
        I'm trying to reduce the hostility of my posts. What parts of this do you feel was hostile? Edit: We've hit the end of the reply chain. I see your point about both the opening and closing sentences. Is there any way to say the first one without coming off as hostile? My goal/point was trying to demonstrate how patently wrong the earlier statements were.
        grzm 10y ago
        I commend your desire to improve your posts. That's something that's always on my mind as well. From my unsolicited, third-party perspective, two things jump out at me. - You could do without the first sentence entirely. - The insinuation that the parent is possibly a shill (an Uber employee) The rest of it is fairly neutral.
- iaw 10y ago
  > allows for a single car to fly from A to B safely "Safely" will never mean a 0% crash rate. So, when a failure occurs that causes the vehicle to crash uncontrollably the property damage and casualty level will be determined largely by the vertical density of the vehicles. > But trucks are less efficient than container ships, and we still use the former when the latter is impossible or too slow Two issues with this: a) the cost difference between container ships and trucks is not so large as that of air and ground travel b) the reason that less efficient trucks are used is exactly because there's an economic demand for delivery and it is the price/time optimal solution. For someone with a commute that can be shortened from 90 minutes to 15 minutes and makes in excess of $250K a year this is a solution. For everyone else it doesn't make sense.
  - jessriedel 10y ago
    The arguments you're making are no more convincing than historical ones like "it will never make economic sense for an individual to pay for their own computer" or "elevators are an inherently dangerous form of travel".
    - iaw 10y ago
      It'll make sense for us to travel to mars, colonize outer space, cure cancer, and a whole host of other things that are presently impossible. Computers and elevators aren't comparable analogies, perhaps the jetpack is?
mahyarm 10y ago
Bridge chokepoints and other small hops over bodies of water / mountains are a great case for flying cars. It would be great for seattle, manhattan, SF, hawaii, islands, etc. You also don't need to build much infrastructure other than landing/takeoff sites. Large infrastructure alone, especially in a place like the USA is a big blocker.

by iaw 10y ago

jessriedel 10y ago

> If the cars broaden vertically it's a safety risk, That's the evidence you're giving to dismiss the ability of flying cars to distribute over multiple altitude? Once we've accepted the hypothetical that technology allows for a single car to fly from A to B safely (which is almost certainly automated), it seems clear that having cars move at different altitude will be trivially possible. > Also, with the advent of KERS and other regenerative systems cars will be able to recapture the bulk of energy consumed for elevation changes. To my knowledge there's no such effective system for planes. So the efficiency on cars is still higher than air vehicles. No one is disputing that regular cars are more efficient than flying cars. But trucks are less efficient than container ships, and we still use the former when the latter is impossible or too slow. You said "Flying is not a valid commute solution and never will be because of physics", and this just isn't true.

inlineint 10y ago
> Once we've accepted the hypothetical that technology allows for a single car to fly from A to B safely (which is almost certainly automated), it seems clear that having cars move at different altitude will be trivially possible. In real world we can't accept this because there are always unpredictable factors, we can only say that probability of a safe flight in a single car is say 99.999%. Then if there are 20 cars one right above another, then probability that none of them crash is only 99.98%, and it could damage all cars below it, so the resulting probability of safe flight in a car reduces to something of order 99.99% instead of 99.999% for a single car. And 99.99% is really not safe enough for everyday flying during many years.
- jessriedel 10y ago
  Avoiding a car that crashes in the lane next to you is a lot harder than avoiding a car that falls 100 feet from above. Yet we have multi-lane highways.
  - iaw 10y ago
    That's an asinine statement if I've ever read one. I've been present for 2 highways collisions, avoiding them is super easy. Which is why full lane closures and multi-car pile-ups are as infrequent as they are relative to the frequency of two car accidents. A vehicle that falls from 100 feet above will be accelerating unlike vehicles in an accident on a highway which will rapidly decelerate. Furthermore, you now have multiple vehicles taking evasive action based on dynamic predictions that cannot incorporate a collision. The second that one car hits another you're going to lose a chunk of your column from pachinko like bouncing. Now, instead of a small mechanical failure you can have drastic loss of life because all of the occupants plummeted to their death. Do you work for Uber?
    - tomcam 10y ago
      Upvoted because you're right, but not sure why you felt it necessary to be so hostile
      - iaw 10y ago
        I'm trying to reduce the hostility of my posts. What parts of this do you feel was hostile? Edit: We've hit the end of the reply chain. I see your point about both the opening and closing sentences. Is there any way to say the first one without coming off as hostile? My goal/point was trying to demonstrate how patently wrong the earlier statements were.
        grzm 10y ago
        I commend your desire to improve your posts. That's something that's always on my mind as well. From my unsolicited, third-party perspective, two things jump out at me. - You could do without the first sentence entirely. - The insinuation that the parent is possibly a shill (an Uber employee) The rest of it is fairly neutral.
iaw 10y ago
> allows for a single car to fly from A to B safely "Safely" will never mean a 0% crash rate. So, when a failure occurs that causes the vehicle to crash uncontrollably the property damage and casualty level will be determined largely by the vertical density of the vehicles. > But trucks are less efficient than container ships, and we still use the former when the latter is impossible or too slow Two issues with this: a) the cost difference between container ships and trucks is not so large as that of air and ground travel b) the reason that less efficient trucks are used is exactly because there's an economic demand for delivery and it is the price/time optimal solution. For someone with a commute that can be shortened from 90 minutes to 15 minutes and makes in excess of $250K a year this is a solution. For everyone else it doesn't make sense.
- jessriedel 10y ago
  The arguments you're making are no more convincing than historical ones like "it will never make economic sense for an individual to pay for their own computer" or "elevators are an inherently dangerous form of travel".
  - iaw 10y ago
    It'll make sense for us to travel to mars, colonize outer space, cure cancer, and a whole host of other things that are presently impossible. Computers and elevators aren't comparable analogies, perhaps the jetpack is?

mahyarm 10y ago

Bridge chokepoints and other small hops over bodies of water / mountains are a great case for flying cars. It would be great for seattle, manhattan, SF, hawaii, islands, etc. You also don't need to build much infrastructure other than landing/takeoff sites. Large infrastructure alone, especially in a place like the USA is a big blocker.