The concept of a flying car will eventually succeed

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Rhino

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The concept of a flying car will eventually succeed
Yep, but probably long after I'm dead. Of course I mean a viable flying car. The concept of a flying car technically succeeded a long time ago. They just haven't made it viable yet. And based on this design they still aren't very close, though they are slowly progressing.
 

jedi

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There are 4 basic forces on any transportation device - Weight, Lift, Drag and Thrust - this is true for cars, trains, submarines, ships and aircraft. There is an interesting concept - the lift per drag ratio - especially as applied to aircraft, that governs how much energy you need for transporting a certain weight a certain range. Currently only winged aerodynamics ensures a high enough L/D to make flight effective. This is true especially for electric propulsion - having limited energy storage due to current battery technology. Fighting gravity all the times with propellers is not the right thing to do - as most "flying cars" are based on multi-copter configuration.

The trick is to have a VTOL configuration for an aircraft to ensure effectiveness in both hovering and cruise configurations. This is hard as demonstrated by more than 70 years of VTOL history. Actually, only 2 designs have evolved to 'life' to be real aircraft and those are military aircraft. I'm of course talking about the V22- osprey - tilt-rotor, and harrier/F-35, the military specification aspect to perform the mission are the reason of their success, the economic cost is secondary.

The civilian market is driven by economics, and as long that the aircraft design compromises too much, it will never be a viable option. Some people believe that the electric propulsion solves the problem, because of the high inherent efficiency, distributed propulsion and other effects, but a hidden aspect that kills the efficiency is the aerodynamics of VTOL. If the aerodynamics is not right, you end up with an inefficient aircraft, that only exacerbates the unwanted characteristics of electric propulsion - the weight and low specific energy of current batteries that for now cannot compete with fuel as a source of energy especially for longer flights.

There is a problem that isn't solved yet for VTOL designs and that is making an aircraft capable of vertical takeoff and landing, but still having high cruise performance and economy. This distils to conflicting requirements for the driving parameters of cruise and hovering performance: L/D drives the performance in cruise and that means large aspect ratio wings, low wetted area and small propeller size. Disk loading and no flow interference drives the hovering performance and that means large rotors and no wings.
Good points. This is the current trend of JOBY. See Aero News Network and current press releases.

Sorry not able to post links at the moment.
 

Dusan

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Interesting fact - I discovered since the physics classes in high school ( a long time ago ) that for transportation you don't need any energy. I other words, all energy you use it's transformed into heat eventually. E.g. for a car - the gasoline your engine burns, some of the energy transforms into mechanical energy to drive the wheels, but that all energy gets converted to heat anyway - friction between mechanical parts, wheel and road, air and vehicle. When you start your vehicle you gain some kinetic energy, but you convert it into heat by stopping at your destination (except electrical cars, that convert some back into electrical and stored back into the batteries). For a conventional gas car, all the energy is converted into heat, equivalent to burning all that gasoline in a fire pit. Transporting something does not need 'transportation energy', so my conclusion was - as a 16 years old - that for transportation you don't need energy and teleporting devices are theoretically possible :) . The transportation is only a byproduct of converting energy into heat, but the effectiveness of the method dictates how much energy you need to convert to heat to achieve your transporting goal.
 
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jedi

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Interesting fact - I discovered since the physics classes in high school ( a long time ago ) that for transportation you don't need any energy. I other words, all energy you use it's transformed into heat eventually. E.g. for a car - the gasoline your engine burns, some of the energy transforms into mechanical energy to drive the wheels, but that all energy gets converted to heat anyway - friction between mechanical parts, wheel and road, air and vehicle. When you start your vehicle you gain some kinetic energy, but you convert it into heat by stopping at your destination (except electrical cars, that convert some back into electrical and stored back into the batteries). For a conventional gas car, all the energy is converted into heat, equivalent to burning all that gasoline in a fire pit. Transporting something does not need 'transportation energy', so my conclusion was - as a 16 years old that for transportation you don't need energy and teleporting devices are theoretically possible :) . The transportation is only a byproduct of converting energy into heat, but the effectiveness of the method dictates how much of the energy you need to convert to heat to achieve your transporting goal.
All true. When we finally get a "flying car" that goes into orbit or to the Moon that will be a whole lot of wasted heat.

The future of aviation is "teleporting devices" and the future is here/now. I am sending this message from my teleport room. I am broadcasting in the blind. If this message is received please push the "like" button on your transporting device. :):popcorn::pilot:
 

Hot Wings

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The Black Fly looks like the best compromise in the small electric multicopter field, so far.
My opinion too, but it's getting into - years - with no real progress.

The future of aviation is "teleporting devices" and the future is here/now. I am sending this message from my teleport room.
Careful with that admission. Zuckerberg just might send his lawyers after you for unauthorized use of his metaverse.

Of course this is all going to change when we discover just how little our government controlled ration of, source approved, discretionary kWhr is.
 

radfordc

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To meet current road safety regulations then a flying car will have to be equipped with airbags and antilock brakes, child safety features and the rest right?
No, not all that stuff. But, to be street legal it does have to meet state regs. Here is a good overview... Are Kit Cars Street Legal? Rules Explained (With Examples)

Enough stuff required to make it a daunting process. This is why some "flying cars" are done as three wheel vehicles so that they qualify as a "motorcycle" instead of a "car".

Not sure if exemptions are available or not.
 
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Rhino

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If I can make my golf cart road legal, and I can, there's no reason why flying cars can't be. That isn't what's holding them back though.
 

Dan Thomas

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Is Twiggy a pilot?
Ha. Most of the folks here will have no idea who Twiggy was. A mid-1960s British model famous for her skinny frame. Looked like a Barbie doll. I think models like this made many girls fret over their weight and would get themselves into eating disorders.

She could get out of the rain by standing under a clothesline....
 

bmcj

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If I can make my golf cart road legal, and I can, there's no reason why flying cars can't be. That isn't what's holding them back though.
Isn’t there a federal vehicle standard? It seems that as long as a vehicle (plane, golf cart, etc) meets the federal code and definition, it should be drivable in all 50 states.
 

Magisterol

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Few month ago a member said there are flying cars already. They are called helicopters. I think there is technology to build a more advanced flying car at least over there in US. The problem is political. European or Trudeau governments are to controlling to allow citizens to have so much freedom. Not fo mention countries like Russia, China and so on and it goes down hill from there... US was always pushing for technology. Curious what the future brings.
 
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