henryk
Well-Known Member
-any positive results in DUCTED fan experiments ?but it works.
(Josef cooperation ...)
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-any positive results in DUCTED fan experiments ?but it works.
300 or more Le Brea Tar pits for collecting moneyIt's estimated that ~300 different companies are designing/building some kind of flying car/VTOL aircraft for the upcoming revolution in travel. Giant drone versions are likely to be the winner. Checkout Homepage Volocopter
I tend to disagree here. The low specific energy of current batteries are emphasising aerodynamic efficiency of the aircraft configuration. Lift per Drag ratio is the parameter that drives the cruise performance regardless of aircraft type. Multi-rotor configurations are worse hover performers than the classical tail-rotor helicopter configuration only because they tend to have higher disk loading, a consequence of simplified control and mechanical design. Edgewise rotors/propellers have anyway a poor Lift per Drag ratio. Conventional helicopters rarely achieve a L/D of 5, I'm not sure of multi-rotors, I haven't seen too many published L/D for them, but I assume they are worse than conventional helicopters - only considering drag interference between multiple rotors, correct me here if I'm wrong.Giant drone versions are likely to be the winner.
Helicopters evolved to look the way they do because that's what worked. Anyone who ever reads aviation history and sees the pictures of all the stuff that was tried will know this. Physics has not changed since the earliest attempts at flight, nor has the air.I tend to disagree here. The low specific energy of current batteries are emphasising aerodynamic efficiency of the aircraft configuration. Lift per Drag ratio is the parameter that drives the cruise performance regardless of aircraft type. Multi-rotor configurations are worse hover performers than the classical tail-rotor helicopter configuration only because they tend to have higher disk loading, a consequence of simplified control and mechanical design. Edgewise rotors/propellers have anyway a poor Lift per Drag ratio. Conventional helicopters rarely achieve a L/D of 5, I'm not sure of multi-rotors, I haven't seen too many published L/D for them, but I assume they are worse than conventional helicopters - only considering drag interference between multiple rotors, correct me here if I'm wrong.
The 'dirtiest' fixed wing aircraft is still able to achieve a L/D of 10 - and this means it needs half the energy to achieve the same range or endurance vs an aircraft having L/D of 5, at similar weight, size and speeds.
This is the reason I believe the next "flying car" (I prefer personal aircraft) will actually have wings and able to transition to a more efficient wing-borne flying mode.
The technical 'battle' is not who has the best motor, or controller or even the highest specific energy battery system - but which configuration is able to achieve the best aerodynamic effectiveness in cruise and hover. The problem here - not solved yet, despite 70+ years of VTOL history - is that Disk Loading determines hover performance and Lift per Drag ratio determines cruise performance, and they are mutually exclusive. A high DL determines a low L/D and vice versa.
-yes !This is the reason I believe the next "flying car" (I prefer personal aircraft) will actually have wings and able to transition to a more efficient wing-borne flying mode.
Oxymoron. You've got your left and right confused....USA Federal Government right wing terminology.
That's actually true. But the thread title says one that will succeed. That requires a viable, marketable product, and we're nowhere near having that. We never will be until we solve the dichotomy of what makes an airplane suitable vs what makes a car suitable. What makes a good plane doesn't make a good car, and vice versa.I think it's actually rather easy to build a flying car...
Been to Los Angeles lately?...Physics has not changed since the earliest attempts at flight, nor has the air....
Referng to post #79 page 4 "left and right confused"? No I do not think so. We must be speaking different languages. I thought the "Federation" was the left and Luke was inclined to the right. Also,** "The Force comes in two flavors: Light Side (good) and Dark Side (bad)."Oxymoron. You've got your left and right confused.
That's actually true. But the thread title says one that will succeed. That requires a viable, marketable product, and we're nowhere near having that. We never will be until we solve the dichotomy of what makes an airplane suitable vs what makes a car suitable. What makes a good plane doesn't make a good car, and vice versa.
Been to Los Angeles lately?
No pitch or collective control of the autorotating section means no control as to where it lands or at what vertical velocity, and it also means little stability. Just about as deadly as without the autorotative feature.
I'll agree if you add, "for how it was being used". The thing is, helicopters never succeeded at fulfilling the role of a flying car, or PAV commuter, or whatever you want to call it. They are too expensive to build, too hard to to operate, too expensive to maintain and far to inefficient to compete with cars in more than 99.99% of potential applications. In fact, they lose pretty drastically to fixed wing airplanes in most applications as well. There is a niche for helicopter operations, as evident by the current helicopter market. However, it's a niche. It's not widespread and never will be without some disruptive technology to overcome the helicopter's inherent limitations.Helicopters evolved to look the way they do because that's what worked.
And that is the key. Some disruptive technology. Every helicopter operator would gladly buy a machine that could do more and cost less. But nobody has come up with such a machine. Nobody. It's not as easy as it seems to the wishful thinkers.There is a niche for helicopter operations, as evident by the current helicopter market. However, it's a niche. It's not widespread and never will be without some disruptive technology to overcome the helicopter's inherent limitations.
You weren't talking about Star Wars. Nor was I.Referng to post #79 page 4 "left and right confused"? No I do not think so. We must be speaking different languages. I thought the "Federation" was the left and Luke was inclined to the right. Also,** "The Force comes in two flavors: Light Side (good) and Dark Side (bad)."
Yep.We are on the verge of politics here so I can't say much more.
The land speeder wasn't a flying car. It didn't travel on roads. And we're talking about Earth, not Tatooine. We have to come up with a concept that works here, and we aren't close to that.To bring the subject back to flying cars, Can we agree that Luke's "land speeder" had successful flying car attributes in spite of it's limited altitude and speed capabilities. It's superior off road capabilities and lack of dependence on airports or sky ports* as the electric VTOL multicopter junkies tend to say is what made it practical.
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