The concept of a flying car will eventually succeed

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henryk

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=multi-pulti, but NO prospective...

ONLY flapping thrusters can solve problem of urban mass flying !

=VOLERIAN type like...
 

Victor Bravo

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π# Henryk, what man-made aircraft has EVER flown with flapping thrusters? *\0/*

%√ What large scale r/c model has EVER demonstrated efficient thrust from this method? >.<
 
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Dan Thomas

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Yup. It's a reality. Here's the reality:

The latest iteration of SkyDrive’s drone-like flying car is powered by a battery and four pairs of propellers and reaches a top speed of 30 mph (48 km/h) for trips of up to 10 minutes. The single-seat flying car has a payload capacity of 30 kg.

A payload of 30 kg. I hope that's a typo. 30kg is 66 pounds. That leaves 100% of North American pilots out of it. Must be a kid flying it in the picture.

And 30 MPH for ten minutes. Going to need some real advances in battery technology to get it a little more practical.

Still, it would be fun. Big fun. For a few minutes, anyway. Wake me up when it does 90 MPH for a couple of hours and carries two of us big folks. You know, the performance of the Bell 47B helicopter of 1946?
 

jedi

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From the internet so it must be true:

1. "A car is a wheeled motor vehicle used for transportation. "

2. "Most definitions of cars say that they run primarily on roads, a railroad vehicle for passengers or freight "

3. "the passenger compartment of an elevator, cableway, airship, or balloon"

4. Example "he was in the elevator when the car stuck""



IMHO if it doesn't have wheels and is to heavy to be carried it is not "roadable" but I note that roadable was not claimed.

It does meet the last two of the four definitions.
 

henryk

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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?
if the car receives any damage does an A&P have to fix it?
 

Dusan

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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.
 

Aesquire

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First, They Aint Cars! Rant, foam. Sigh.


The Black Fly looks like the best compromise in the small electric multicopter field, so far.

The "breakthrough" there isn't so much the wings as it is just ignoring the pilot /fuselage standard configuration.

All the "tail sitter" planes that actually flew, the Lockheed Salmon, Ryan Vertijet, Convair Pogo, and SNECMA Coleoptere, ( did I miss any? ) had the stupidly difficult problem of flying backwards to land & bad pilot visibility & ergonomics.

The Osprey and the various tilt rotor & tilt wing planes have struggled with propeller size choice. The huge rotors on the V-22 are the compromise to get good hover capability.

Black Fly simply doesn't care that you lay a bit head down & can't look straight down on landing. Let George do it!

I've long preferred vectored thrust VTOLs like Harrier or the Bell X-14, Or deflected thrust like the Ryan VZ-3. The latter seems more promising for home building. A wing with big complex flaps seems easier than complex engine mounts and entire wings on hinges.
 
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