Defying gravity, the flying future.

[Hersbird]

The human powered helo will have trouble getting that last bit. Getting some liftoff is easy but once you lose the ground effect then you need much more power. When my toy helicopter's battery is almost dead it still with easily fly along the ground like a hovercraft, no higher. How they are trying for the 10 foot mark in that NPR video is with huge rotors. The effect is based on rotor diameter, and goes to zero at about 1 1/4 rotor diameter. It's really effective and 1/4 rotor diameter so by having a 40' rotor diameter they can get a 20-25% boost in lift up to 10 feet.

[redpoint5]

Originally Posted by All Darc

The most efficient transport will be hyperloop, vehicles in vacuum tubes, and the few required energy it's produced by solar panels. Not sure if it can have a good use for cities, since it will be very expensive.

For flying maybe in future people will need to have solar panels and get credits of produced energy to be allow to fly in electric vehicles. A week or so to produce energy to a short flying trip.

But even if energy wasn't a problem, the flying vehicles took far more space to navegate than road cars, since the require distance for safety it's giant. If 0,1% of people in big cities had a helicopter, there sould be no enough space on air.

The expense isn't in the energy, but in the contraption itself and liability. The electricity to fly 100 miles is relatively insignificant.

Hyperloop seems too complicated to work. There is the problem of loading and unloading pods at each end. I tend to think this will never be widely used.

Concerning airspace; there is lots. Traveling in 3 dimensions opens up a lot of room for travel, even if large distances need to be maintained between aircraft. Besides, the point of air travel isn't to replace normal commuting, but to skip over congested areas when time is more valuable than money.

Originally Posted by All Darc

It's strange how this vehicle (small propellers) have a total propeller area looking smaller than human transport drones with fewerm and larger propellers.

The Skydriver looks really impossible, since I see no compartment for batteries :

I see no redundancy, which is important when you have paying passengers using the aircraft.

[Xist]

Curious. I shared a battery-powered plane that had eighteen small motors and two large ones, with skinny wings, but I cannot find it now. It was a NASA project.

[gone-ot]

Originally Posted by Xist

Curious. I shared a battery-powered plane that had eighteen small motors and two large ones, with skinny wings, but I cannot find it now. It was a NASA project.

Were you referring to this?

[redpoint5]

Electric flight only makes sense for short trips (my guess is ~100 miles or less). Those distances are usually covered by ground transport, so the only reason to fly electric then would be to avoid rush hour congestion.

Mostly I think this will be a status symbol for the wealthy.

Besides all that, we have had efficient VTOL flight for decades; it's called a helicopter. There is nothing special about electric multi-rotors that make them better suited to autonomous flying compared to a helicopter. The same gyros, route finding, and sensors are used for both.

[All Darc]

What about the suposed inovation for batteries, with some one reported as having potential to 10x the energy density of lithium ?


Fisker files patents on solid-state battery technology; anticipating automotive-ready from 2023 - Green Car Congress

https://www.youtube.com/watch?v=fhP40Dff04Y

https://www.youtube.com/watch?v=B-F8NerrH7Y

If sodium batteries with 10x more energy became reality, and electric motors with more power per Kg also became a reality, we will have future vehicles that will be just a egg shell with wheels. In wheel motors with battery pack in the floor, and all inside space to enjoy.

Originally Posted by redpoint5

Electric flight only makes sense for short trips (my guess is ~100 miles or less). Those distances are usually covered by ground transport, so the only reason to fly electric then would be to avoid rush hour congestion.

Mostly I think this will be a status symbol for the wealthy.

Besides all that, we have had efficient VTOL flight for decades; it's called a helicopter. There is nothing special about electric multi-rotors that make them better suited to autonomous flying compared to a helicopter. The same gyros, route finding, and sensors are used for both.

[All Darc]

It remambers Howard Hughes big plane, Hercules.




I wonder if it, despite managed to fly, it could ever fly loaded with troups and equipment, as it was designed for, or if could only fly unloaed. In the movie (The Aviator) if only took off after the engines was in maximum,but we can' trust a movie.

Originally Posted by Old Tele man

Were you referring to this?

[redpoint5]

Originally Posted by All Darc

If sodium batteries with 10x more energy became reality, and electric motors with more power per Kg also became a reality, we will have future vehicles that will be just a egg shell with wheels. In wheel motors with battery pack in the floor, and all inside space to enjoy.

I'm doubtful of batteries with 10x more energy. There is a limit to chemistry and physics. Batteries currently have about 1% of the energy density of gasoline.

Originally Posted by All Darc

It remambers Howard Hughes big plane, Hercules.

I wonder if it, despite managed to fly, it could ever fly loaded with troups and equipment, as it was designed for, or if could only fly unloaed. In the movie (The Aviator) if only took off after the engines was in maximum,but we can' trust a movie.

The Spruce Goose is in a museum near where I live. It did fly very briefly in real life.

https://www.youtube.com/watch?v=OXZQewzdWzA

[gone-ot]

Originally Posted by All Darc

It remambers Howard Hughes big plane, Hercules.




I wonder if it, despite managed to fly, it could ever fly loaded with troups and equipment, as it was designed for, or if could only fly unloaed. In the movie (The Aviator) if only took off after the engines was in maximum,but we can' trust a movie.

Takeoff from water requires MORE power than similar takeoff from land because of water's much greater density than air...as soon as the aircraft "breaks/leaves" the water and is flying/moving only thru air, much less power is needed. I worked for Hughes Aircraft Company.

[acparker]

Regarding traffic congestion, personal flying vehicles will only move the congestion to the sky. Freeways were supposed to alleviate the congestion of surface streets. We know how well that worked.

The hyperloop is probably technically achievable, at least for a short distance, but will never make economic sense. Elon Musk is the ultimate monorail salesman. When will people learn to just shut him out?

Electric and hybrid airplanes seem to make the most sense in highly populated areas where noise and pollution are issues.

Ducted fans can be efficient, but they are not always more efficient than an open propeller. You can get some of the benefits of ducting by putting winglets on the propeller tips, like the Hartzell Q-tip. Drone companies are also introducing prop winglets for quieter operation and some performance enhancement.

Using arrays of many small ducted fans could reduce the aerodynamic penalties of ducted fans, but at a point, it may be easier to simply duct high pressure air from a central compressor.