Delorean Aerospace

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tspear

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Claims 2 and 3 in the patent they reference state that the centers of pressure for the fans are above the cg and that the fans can be rotated side to side as well as fore and aft.
Nice research, I did not chase the patent....

Tim
 

Topaz

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As usual, call me when they have a prototype that flies out of ground effect.

These things constantly bubble up, chasing the technology darling du jour. These days, flying cars are back in vogue, thanks to Uber, Airbus, and Terrafugia. So you're going to see a lot of "renderware" (love that term, going to steal it shamelessly) out there pushing flying cars. Some of it is genuinely well-intentioned, some of it is just a framework set up to suck up investor money. Few pieces of actual hardware will be built in either case, and eventually we'll be on to the next new-business fad. It's a lot like the "amazing new engine" things we see every few months, with the same results.

So few of these people, including the well-intentioned ones, have even the slightest clue about what it takes to do a practical VTOL design. Even the aerospace primes have taken decades of dedicated research to figure it out. It's not just about lift props. Most of the control schemes out there - including this one - are so woefully inadequate that the airplane couldn't fly and transition from horizontal to vertical flight and back at all, let alone reliably and well.
 

pictsidhe

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Thanks for the post I couldn't be bothered to write, Topaz! One look at this thing told me that the designer has far less of a clue about aerodynamics than I, as a self confessed amateur, do. Sharp edges aft of the front fan. A NACA scoop for the rear fan. Suspiciously small fans and a serious lack of tail fin area. 6 wings, ffs! It certainly won't fly particularly well if it ever gets off the ground.
 

cheapracer

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Remember this guy worked for Mattel.

His angle could be to generate a lot of publicity, and then sell the model and marketing rights to them with the help of ex-associates approving it ..
 

Topaz

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... I have the perfect way to make a fortune in aviation nowdays... we start a company specializing in static display flying car mock-ups for the PR photos and trade show displays, and vaporware website content. We cater to the folks who are floating out investment financing rounds, who have no intention of creating an actual flying machine. We get Autoreply and his fast-execution composite crew to build it in a few hours. Fritz, Sockmonkey, and a few of the other guys can do the artistic renderings (which will substitute for plans, blueprints, etc.), and the fancy CFD "clown puke" (which will substitute for all realistic aerodynamic studies). I'm sure we can even find someone to write the ridiculous BS that makes huge claims, but BS that creates more questions than it answers... hey wait a minute... that's me :whistle:
This happens a lot more than we would hope, and not just in aviation. Not saying these DeLorean folks are doing that, because we can't really know, but there's a lot of it out there.
 

Topaz

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Claims 2 and 3 in the patent they reference state that the centers of pressure for the fans are above the cg and that the fans can be rotated side to side as well as fore and aft.
So differential thrust for pitch control, differential slewing of the fans side-to-side for yaw control. What about positive roll control? Simple pendulum stability isn't nearly enough. Also, this is all electric, I believe. They have enough power to those tiny fans to create sufficient thrust not only for vertical lift, but also when the fans are diverted for yaw control and during transition to horizontal flight, before the wings take over the job but while the fans are still vectored somewhat aft to accelerate the vehicle forward? Positive three-axis control in all phases of flight and enough power to provide both enough vertical lift and enough forward thrust to accelerate to forward flight simultaneously have long been the bugbears of VTOL design.

Here's a perfect example. He has just enough thrust to lift the aircraft vertically off the ground and rise, but not enough to support the airplane when pitched forward to provide thrust to accelerate, even slightly. You can see the airplane stop and then rise vertically, but every time he tries to move forward, the airplane sinks. If, like the DeLorean team is doing, you also deflect main lift thrust for control purposes, it just gets worse, unless you've got a lot of excess power available. For an electric, "excess power" is hardly something easily on-tap, especially for a VTOL machine where the weight of batteries rapidly becomes very large.

[video=youtube;_3yjpX54s_U]https://www.youtube.com/watch?v=_3yjpX54s_U[/video]
 
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tspear

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So differential thrust for pitch control, differential slewing of the fans side-to-side for yaw control. What about positive roll control? Simple pendulum stability isn't nearly enough. Also, this is all electric, I believe. They have enough power to those tiny fans to create sufficient thrust not only for vertical lift, but also when the fans are diverted for yaw control and during transition to horizontal flight, before the wings take over the job but while the fans are still vectored somewhat aft to accelerate the vehicle forward? Positive three-axis control in all phases of flight and enough power to provide both enough vertical lift and enough forward thrust to accelerate to forward flight simultaneously have long been the bugbears of VTOL design.

Here's a perfect example. He has just enough thrust to lift the aircraft vertically off the ground and rise, but not enough to support the airplane when pitched forward to provide thrust to accelerate, even slightly. You can see the airplane stop and then rise vertically, but every time he tries to move forward, the airplane sinks. If, like the DeLorean team is doing, you also deflect main lift thrust for control purposes, it just gets worse, unless you've got a lot of excess power available. For an electric, "excess power" is hardly something easily on-tap, especially for a VTOL machine where the weight of batteries rapidly becomes very large.

[video=youtube;_3yjpX54s_U]https://www.youtube.com/watch?v=_3yjpX54s_U[/video]
There was one drone design I did read a while back on which had an interesting approach to this. Climb higher then required and trade altitude for speed and time.
I think the total energy expended was going to be slightly higher due to loss of efficiency but the belief was over weight due to small props and engines. So for their purposes, it was worth the trade off. Do not think this would work for the car posted here though.....

Tim
 
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Swampyankee

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People have been chasing flying cars longer than fusion. Molt Taylor's flew and drove, which is an endpoint that seems forgotten by the latest generation of flying cars.

Sixty-plus years and barely tied. Not bad for Mr Taylor's design.
 

BJC

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People have been chasing flying cars longer than fusion. Molt Taylor's flew and drove, which is an endpoint that seems forgotten by the latest generation of flying cars.

Sixty-plus years and barely tied. Not bad for Mr Taylor's design.
I don't have any desire to have a flying car, but it should be noted that Molt's machine differed from today's computer generated concepts. Molt's machine was a car that attached to a wing and tail that were left on the airport when in car mode. I have seen Molt's machine both in the air and on the road; there is no doubt that Molt's flies much better than the Terrafuga.


BJC
 

Topaz

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I don't have any desire to have a flying car, but it should be noted that Molt's machine differed from today's computer generated concepts. Molt's machine was a car that attached to a wing and tail that were left on the airport when in car mode. I have seen Molt's machine both in the air and on the road; there is no doubt that Molt's flies much better than the Terrafuga.


BJC
All agreed. On the Aerocar III, the tail and wings could be towed behind the car as a trailer. Added even more utility.
 
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Victor Bravo

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"Renderware"... that's brilliant, accurate, and tells the whole story in one word. Should immediately be put into all aviation dictionaries and reference books.

Topaz' mention of having some amount of credibility only once it has gone out of ground effect is also spot on. Let's coin another phrase based on that notion... BGE "beyond ground effect".

The funniest thing about all of this to me, is that nobody in the modern whiz-bang "renderware" or "investorware" age seems to pay attention to what has been shown to work. The totally crazy unfathomable aspect of this is that sane and successful investors traditionally want to have some assurance that a consumer product is based on something that has been shown to work. The "miracle" level stuff is usually left to the university and huge corporate research grant type of funding.
 

BJC

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"Renderware"... that's brilliant, accurate, and tells the whole story in one word. Should immediately be put into all aviation dictionaries and reference books.

Topaz' mention of having some amount of credibility only once it has gone out of ground effect is also spot on. Let's coin another phrase based on that notion... BGE "beyond ground effect".

The funniest thing about all of this to me, is that nobody in the modern whiz-bang "renderware" or "investorware" age seems to pay attention to what has been shown to work. The totally crazy unfathomable aspect of this is that sane and successful investors traditionally want to have some assurance that a consumer product is based on something that has been shown to work. The "miracle" level stuff is usually left to the university and huge corporate research grant type of funding.
It seems that most people, including potential investors, potential owners, magazine editors, etc. have absolutely no understanding of what it means to design something. Just create some futuristic looking machine out of bits and bytes, throw them at some pixels, and presto - it is.

Sad, really.


BJC
 

BBerson

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Aircar took flack for his opinion that these VTOL schemers are scammers. I bet Aircar is still penniless while these schemers get rich.
 

pictsidhe

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Maybe someone could write an article about these miracle machines, with some actual facts and engineering in it? I'm tempted to try myself, but I'm a nobody.
 

mcrae0104

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It seems that most people, including potential investors, potential owners, magazine editors, etc. have absolutely no understanding of what it means to design something.
And often, you can put the "designer" in the same camp.
 
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