Folding wings

[mindenpilot]

OK, you have to humor me on this.
I'm not talking about anything unrealistic (like Moller's skycar, etc).
But what would prevent a design (even low performance/ultra light to start)
that would allow a pilot to fly into an airport, then fold up his wings and
cruise down surface streets at 45mph?

It doesn't sound that complex. I bet a homebuilder could do it with parts
laying around his garage.
The only serious issue I can think of is having a spinning prop on a city
street.
Even so, couldn't you "disengage" the prop and then couple the engine to the
mains somehow?
I realize that is a bit more complex and would mean some kind of
transmission.
I'm just throwing out ideas here.

It sure would be nice not to rent a car or get a taxi!
It also seems that there would be a MUCH larger interest in GA if people
could potentially commute this way.
For example, I would consider working in Reno and living in Minden if I
could fly into Reno, then commute to my work.

I'm serious about this, but I'm ready for the flames ;-)

Adam
N7966L
Beech Super III

[aluckyguess]

I like it. And it woud cuise at 200 mph.
"mindenpilot" > wrote in message
...
> OK, you have to humor me on this.
> I'm not talking about anything unrealistic (like Moller's skycar, etc).
> But what would prevent a design (even low performance/ultra light to
> start) that would allow a pilot to fly into an airport, then fold up his
> wings and cruise down surface streets at 45mph?
>
> It doesn't sound that complex. I bet a homebuilder could do it with parts
> laying around his garage.
> The only serious issue I can think of is having a spinning prop on a city
> street.
> Even so, couldn't you "disengage" the prop and then couple the engine to
> the mains somehow?
> I realize that is a bit more complex and would mean some kind of
> transmission.
> I'm just throwing out ideas here.
>
> It sure would be nice not to rent a car or get a taxi!
> It also seems that there would be a MUCH larger interest in GA if people
> could potentially commute this way.
> For example, I would consider working in Reno and living in Minden if I
> could fly into Reno, then commute to my work.
>
> I'm serious about this, but I'm ready for the flames ;-)
>
> Adam
> N7966L
> Beech Super III
>
>

[George Patterson]

mindenpilot wrote:
>
> But what would prevent a design (even low performance/ultra light to start)
> that would allow a pilot to fly into an airport, then fold up his wings and
> cruise down surface streets at 45mph?

It's been done at least twice. These days, I'd bet the safety equipment required
for highway vehicles in the U.S. would weigh enough to make it absolutely
impossible.

The two approaches I've read about are 1) Have the wings and empennage attach
to the car. The car lands, unhooks the assembly, and leaves it at the airport.
2) Use detachable and folding wings and tailfeathers and trailer them. The EAA
museum at Oshkosh has one of these on display.

These didn't make very good airplanes because of the weight of the automobile
running gear. IIRC, only three of design #2 were built, and I think that was in
the 50s.

George Patterson
He who would distinguish what is true from what is false must have an
adequate understanding of truth and falsehood.

[Jose]

> I'm not talking about anything unrealistic (like Moller's skycar, etc).
> But what would prevent a design (even low performance/ultra light to start)
> that would allow a pilot to fly into an airport, then fold up his wings and
> cruise down surface streets at 45mph?

What is the difference between the skycar and what you describe?

Nothing prevents you from designing something like that, but what will
result is an airplane that doesn't fly very well, and a car that
doesn't drive very well. All the stuff you'll need to carry around in
order to be able to safely drive the vehicle on roads after landing
would need to be carried as part of the airplane, making it heavier
and lowering its payload. This includes the extra weight used to make
the vehicle crashworthy (assuming you would like to survive a battle
between you and a Toyota). And all the stuff you need to fly with
would need to be carried while driving on the ground - this means
you'd be dragging the wings and tail all over the place. You would
probably not be carrying fuel in the (detachable) wings, so the fuel
tank would be in the empenage, which has weight and balance consequences.

The tradeoffs would make the engineering much more difficult than you
suspect, and the result would be sub-optimal in all motion regemes.
Put another way, for the same performance, you'd spend lots more
money, and you'd be better off having a cab waiting for you.

Further, every time you wanted to take off, you'd have to reassemble
the airplane - at the very least, you'd have to put the wings back on.
The fasteners would be a weak point, and the time spent doing that
would reduce the time savings of commuting by air this way. Looking
(cynically) into the future, with all the TSA stuff coming down, such
a vehicle would probably be seen as a threat to security, and you
might end up on the receiving end of hours of security questioning
every time you wanted to take off or drive away, especially at a new
airport.

If you are thinking of doing this for commuting, you'd be better off
leaving a car in Reno for your commute, and flying in a regular plane
from Minden. If you are thinking of it for the coolness factor,
what's wrong ith Moller's aircar?

Jose
--
Nothing is more powerful than a commercial interest.
for Email, make the obvious change in the address.

[Jose]

> [A flying car] doesn't sound that complex.

Here's a link to the history of flying cars which you might find
informative.
http://www.haynes-aero.com/Netscape/frames.html
Jose
--
Nothing is more powerful than a commercial interest.
for Email, make the obvious change in the address.

[mindenpilot]

> All the stuff you'll need to carry around in order to be able to safely
> drive the vehicle on roads after landing would need to be carried as part
> of the airplane, making it heavier and lowering its payload. This
> includes the extra weight used to make the vehicle crashworthy (assuming
> you would like to survive a battle between you and a Toyota). And all the
> stuff you need to fly with would need to be carried while driving on the
> ground - this means you'd be dragging the wings and tail all over the
> place. You would probably not be carrying fuel in the (detachable) wings,
> so the fuel tank would be in the empenage, which has weight and balance
> consequences.


I don't think those electric vehicles made for surface streets (basically
golf carts) have any safety features.
Maybe this aircraft could find a similar loop hole.


> The tradeoffs would make the engineering much more difficult than you
> suspect, and the result would be sub-optimal in all motion regemes. Put
> another way, for the same performance, you'd spend lots more money, and
> you'd be better off having a cab waiting for you.

I agree that the result would be less than optimal in both aspects.
I think that would be a minor price to pay.
Start with something simple...single seat, perhaps.
I'd be looking for something that could carry me (175lbs) 100nm @ 70mph,
then scoot me along another 30mi on the ground at 45mph.
I don't think you need much to achieve that kind of performance.

Let's not give up the dream yet!

[mindenpilot]

> What is the difference between the skycar and what you describe?

I'm not talking about VTOL.
Just extending what airplanes are already doing.
They fly...
They taxi...
A lot of homebuilts have wings that remove in 5 minutes.

[Morgans]

"mindenpilot" > wrote

> OK, you have to humor me on this.
> I'm not talking about anything unrealistic (like Moller's skycar, etc).

***Unfortunately, it is unrealistic.

> But what would prevent a design (even low performance/ultra light to
start)
> that would allow a pilot to fly into an airport, then fold up his wings
and
> cruise down surface streets at 45mph?

***Weight.

> It doesn't sound that complex. I bet a homebuilder could do it with parts
> laying around his garage.

***If it was not complex, it would have been done by now, by someone much
more brilliant than you and me.

> The only serious issue I can think of is having a spinning prop on a city
> street.
> Even so, couldn't you "disengage" the prop and then couple the engine to
the
> mains somehow?
> I realize that is a bit more complex and would mean some kind of
> transmission.

***Weight AND complexity, and lots of it.

> I'm just throwing out ideas here.
>
> It sure would be nice not to rent a car or get a taxi!
> It also seems that there would be a MUCH larger interest in GA if people
> could potentially commute this way.
> For example, I would consider working in Reno and living in Minden if I
> could fly into Reno, then commute to my work.
>
> I'm serious about this, but I'm ready for the flames ;-)
>
> Adam

No flames from me, but the problems are great, and the solutions are few.
In a world of building airplanes, you work to save ounces, and all the
things needed for your idea adds tens and fifties of pounds, for each extra
item needed.

A plane is said to be a system of compromises, flying in loose formation.
When you add all the extra stuff needed for an airplane car, it is way *too
* much of a compromise, and likely not be a good airplane, or car.
--
Jim in NC

[mindenpilot]

> ***If it was not complex, it would have been done by now, by someone much
> more brilliant than you and me.

I understand the point you're making, but I'm an optimist.
It doesn't take a genious to be an entrepreneur (thank goodness), otherwise
there would be a lot fewer businesses!
There are all kinds of high-tech approaches out there (as have been pointed
out to me).
While admirable, they may be making the problem (my specific application)
more complicated than it needs to be.


I propose a simple airframe, like a C-152, or heck, even a mini-MAX, whose
wings come off quickly.
For ground transportation, remove the wings, and add a cage around the prop
(like on powered parachutes).
Add some turn signals, brake lights, etc, and that's it.
Nothing more.
What more do you need?
Then you just taxi it.
It doesn't need to go on the freeway, just surface streets.


>
> No flames from me, but the problems are great, and the solutions are few.
> In a world of building airplanes, you work to save ounces, and all the
> things needed for your idea adds tens and fifties of pounds, for each
> extra
> item needed.


For the added weight, is the solution as simple as adding power?
In the example I listed above, couldn't you put a 200HP engine (as an
example) onto the smaller airframe to make up for any added weight?


>
> A plane is said to be a system of compromises, flying in loose formation.
> When you add all the extra stuff needed for an airplane car, it is way
> *too
> * much of a compromise, and likely not be a good airplane, or car.
> --
> Jim in NC
>

Again, I don't think (at first), the design needs to be particularly good at
either flying or driving.
Proof of concept is all I would be looking for initially.
If it flew reasonably well for short commuter trips, and was able to
negotiate the surface streets, that would be great.

I bet more than one reader of this group (maybe the homebuilt group) could
hack something together in no time.
It would then be reasonably easy to get it certified as experimental.
What about certified to drive on the road?
Keep in mind the golf carts that are road legal...

Adam
N7966L
Beech Super III

[Morgans]

"mindenpilot" > wrote

> For the added weight, is the solution as simple as adding power?
> In the example I listed above, couldn't you put a 200HP engine (as an
> example) onto the smaller airframe to make up for any added weight?

Now I have to flame.

For you to ask a question, like the one above, shows you have little
understanding of engineering or design. You are clueless. You don't have
a chance of making your proposal working, or even a chance of understanding
enough to discuss it in a rational manner.

Stick to flying, and forget the designing. Bye.
--
Jim in NC

[Brian]

I wonder how many times the Wright Brothers heard this statement or
something like it.

I agree the challenges are great and his statement ignores many
engineering issues that are required for adding additional weight to
the airplane (i.e. Additional wing area required, Addtional structure
required, the Addtional weight of these additional structures) I can
come up with many well reasoned and logical reasons why it won't work.

I think the Wright brothers were probably in the same boat when they
started, But their greatest acheivement was their ability to solve
difficult problems and question and attempt to prove or disprove all
the known issues. They started off with little understanding of
engineering and design (related to aircraft) and were clueless as to
the what it would take to acheive flight, So they taught themselves in
a way that no one else had and as result were successful.

I remember when the Rubik's cube 1st came out I had no Idea how it
could do what they it did. After I had disassembled it it seemed easy.

I am careful to tell people what the can't do, while most will fail. A
few are just clueless and crazy enought to be succesfull.

Brian

[Jose]

> ...Add some turn signals, brake lights, etc, and that's it...

Whatever the contraption, could you take it around an obstacle course?
To my knowledge there's only one tricycle CAR in the world (it's
British). There's a reason.

> For the added weight, is the solution as simple as adding power?

We did this with model rockets - took a little one designed for a 1/4A
engine and put a C6-5 in it. The engine went higher than we could
track, the fins remained on the launch pad.

> For the added weight, is the solution as simple as adding power?

I'm pretty sure it's already been done. But there's a bit more to it
than just taxiing on the street. It needs to be safe on the street.

Jose
--
Nothing is more powerful than a commercial interest.
for Email, make the obvious change in the address.

[Chris W]

mindenpilot wrote:

>OK, you have to humor me on this.
>I'm not talking about anything unrealistic (like Moller's skycar, etc).
>But what would prevent a design (even low performance/ultra light to start)
>that would allow a pilot to fly into an airport, then fold up his wings and
>cruise down surface streets at 45mph?
>
>

Just for fun, lets explore this idea some more. Obviously weight is the
biggest problem or you could just mount a folding wing, tail feathers
and prop to your Honda. The weight of a transmission to drive the
wheels directly alone would probably add to much weight to be
practical. So you suggested driving it with the prop with some kind of
cage around it. If you are going to put a cage around the prop, you
might as well make it useful. Make it a pusher prop with a ducted fan
instead of a normal simple prop. I think some home builder is working
on a design like that. Second have you ever noticed how amazingly
horrible the ground handling of every airplane I have ever seen is? To
make it road worthy, even if just for non-highway use, you would have to
have a more car like suspension. That of course is going to add a
significant amount of weight to the machine. One of the reasons
airplanes are so unstable on the ground is, by necessity the main wheels
need to be pretty close to the CG. I'm not sure you could get good
ground handling with out moving the main wheels further from the CG.
Tires alone are going add a huge amount of weight, if you try and drive
around on typical airplane tires you are going to be replacing them
every time you turn around. Finally brakes, you are never going to
drive a vehicle like this on the road with out a much better brake
system than most airplanes have, and again that is going to add a lot of
weight. As another poster so rudely put it, no you can't make up for
weight with more horse power. Obviously it can and has been done, but I
doubt you will ever see a flying car that can drive or fly very good at
all.

A much better idea is a flying garage :) Just get a small car and a
DC-3, and you have the best of both worlds :)

--
Chris W

Gift Giving Made Easy
Get the gifts you want &
give the gifts they want
http://thewishzone.com

"They that can give up essential liberty
to obtain a little temporary safety
deserve neither liberty nor safety."
-- Benjamin Franklin, 1759 Historical Review of Pennsylvania

[aluckyguess]

Anti-Gravity ?
If there is a will there is a way. I think the only thing keeping it from
happening is the cost. There is no way to make it cost efficient at this
time.

[Corky Scott]

On Sun, 6 Feb 2005 19:25:59 -0800, "mindenpilot"
> wrote:

>OK, you have to humor me on this.
>I'm not talking about anything unrealistic (like Moller's skycar, etc).
>But what would prevent a design (even low performance/ultra light to start)
>that would allow a pilot to fly into an airport, then fold up his wings and
>cruise down surface streets at 45mph?

Here is a website describing Moult Taylors Aerocar as well as other
types.

http://www.fiddlersgreen.net/aircraft/private/aerocar/info/info.htm

Corky Scott

[[email protected]]

Chris W wrote:
>
> Just for fun, lets explore this idea some more. Obviously weight is
the
> biggest problem or you could just mount a folding wing, tail feathers

> and prop to your Honda.

That's pretty much what past attempts at flying cars have done.
Google for "aerocar" and "convaircar". For a more current project,
head on over to http://www.aerocar.com/ and see the Aerocar 2000.
It's pretty much the same concept with a Lotus Elise. One of Molt
Taylor's last efforts at a flying car came in the 80s. I think it was
called the Aerocar IV and consisted of a Honda CRX with detachable wing
and tail assembly. As I recall, that one had a 500 shp turboprop.

John Galban=====>N4BQ (PA28-180)

[Corky Scott]

On Mon, 07 Feb 2005 15:13:56 GMT, Jose >
wrote:

>> ...Add some turn signals, brake lights, etc, and that's it...
>
>Whatever the contraption, could you take it around an obstacle course?
> To my knowledge there's only one tricycle CAR in the world (it's
>British). There's a reason.

Hmmm, a small ATV with a detachable powered chute? You won't get
anywhere fast but a big enough chute might carry the thing.

Corky Scott

[Hank Rausch]

Here's something like what you are looking for--a roadable vehicle that
can fly. It is a parachute conversion for a Honda Reflex motorcycle.



http://www.ultralightnews.com/airventure2001/flitebike.htm

[Kyler Laird]

George Patterson > writes:

>The two approaches I've read about are 1) Have the wings and empennage attach
>to the car. The car lands, unhooks the assembly, and leaves it at the airport.
>2) Use detachable and folding wings and tailfeathers and trailer them. The EAA
>museum at Oshkosh has one of these on display.

A (Lotus) concept car for #1 was on display at Oshkosh a couple years ago.

--kyler

[Kyler Laird]

Jose > writes:

> To my knowledge there's only one tricycle CAR in the world (it's
>British).

http://www.3wheelers.com/azlist1.html

> There's a reason.

Laziness?

--kyler

[CryptWolf]

"Chris W" > wrote in message
news:0ILNd.1855$53.928@lakeread07...
> mindenpilot wrote:
>
> A much better idea is a flying garage :) Just get a small car and a
> DC-3, and you have the best of both worlds :)

Most twins and some larger singles could handle the weight of
a motorcycle and perhaps even a passenger. Getting it through
the door might be a problem on many models.

For example, my old 1988 Kawasaki 750 Ninja is a tad bit over
500 pounds wet and my 1980 KZ750 was around 500 pounds dry.
Note that these are fairly large motorcycles and a modern 500
or 250 would be even lighter. My stripped down 1973 RD350 Yamaha
probably tops out at 200 pounds or less wet.

A custom design retaining system and removal of the seats
would even make the weight and balance mostly happy. Probably
even easy enough for one person to load. A lot depends on
the size of the motorcycle and how well the design handles the
weight. We'll pretend we have doors big enough to handle it.

The FAA might have something to say about having several gallons
of gasoline in the cockpit and removing the seats or replacing them
as needed. All that is up to the engineers and the lawyers.
I'm just the idea man. :)

[Jose]

>> To my knowledge there's only one tricycle CAR in the world (it's
>> British).

> http://www.3wheelers.com/azlist1.html
>

Wow. I had no idea there were that many nut cases in the world! :)

In all fairness, many of these barely qualify as golf carts, let alone
cars. But I am surprised that so many people have made three-wheeled
vehicles with the intention of driving them on the same roads the
hummer uses.

Heck, why not just taxi an RV-3 on the streets and call it a done deal?

Jose
--
Nothing is more powerful than a commercial interest.
for Email, make the obvious change in the address.

[Morgans]

"CryptWolf" > wrote

> Most twins and some larger singles could handle the weight of
> a motorcycle and perhaps even a passenger. Getting it through
> the door might be a problem on many models.

There you go! Much better solution than an aircar, made of unobtanium!

Some of the small scooters are smaller, and lighter, which should help
loading singlehanded.

The way around the door size issue and the seats, ect, is to go
experimental. You can do pretty much as you please, modification wise. A
number of designs could handle the loading and weight requirements.
--
Jim in NC

[Morgans]

"Hank Rausch" > wrote in message
oups.com...
> Here's something like what you are looking for--a roadable vehicle that
> can fly. It is a parachute conversion for a Honda Reflex motorcycle.
>
>
>
> http://www.ultralightnews.com/airventure2001/flitebike.htm
>

Except he could easily do the trip twice as fast in a car, as with a
parachute and motorcycle. The wind limitations of a powered chute could
eliminate 50% or more of the days that would otherwise be flyable.
--
Jim in NC

[mindenpilot]

"Brian" > wrote in message
oups.com...
>I wonder how many times the Wright Brothers heard this statement or
> something like it.
>
> I agree the challenges are great and his statement ignores many
> engineering issues that are required for adding additional weight to
> the airplane (i.e. Additional wing area required, Addtional structure
> required, the Addtional weight of these additional structures) I can
> come up with many well reasoned and logical reasons why it won't work.
>
> I think the Wright brothers were probably in the same boat when they
> started, But their greatest acheivement was their ability to solve
> difficult problems and question and attempt to prove or disprove all
> the known issues. They started off with little understanding of
> engineering and design (related to aircraft) and were clueless as to
> the what it would take to acheive flight, So they taught themselves in
> a way that no one else had and as result were successful.
>
> I remember when the Rubik's cube 1st came out I had no Idea how it
> could do what they it did. After I had disassembled it it seemed easy.
>
> I am careful to tell people what the can't do, while most will fail. A
> few are just clueless and crazy enought to be succesfull.
>
> Brian
>

My thoughts exactly. I was prepared for the flames, but this was my
underlying belief.
BTW, I am an exceptionally accomplished engineer, which is perhaps why some
things seem more possible to me than to others.

Once more, I am not proposing anything pretty or elegant at first, just
something that will work.
Hell, a mini-MAX will work right now (aside from street-legal issues).
It will fly, the wings come off in 10 minutes, then you could taxi it.

Let's make it more elegant from there...

Adam
N7966L
Beech Super III

[mindenpilot]

> Whatever the contraption, could you take it around an obstacle course? To
> my knowledge there's only one tricycle CAR in the world (it's British).
> There's a reason.

I suppose it doesn't HAVE to be a car.
Honda makes a GoldWing trike that works just fine.

> I'm pretty sure it's already been done. But there's a bit more to it than
> just taxiing on the street. It needs to be safe on the street.

I agree. This is where I think the majority of ingenuity and design would
be required.

Adam
N7966L
Beech Super III

[mindenpilot]

"Corky Scott" > wrote in message
...
> On Mon, 07 Feb 2005 15:13:56 GMT, Jose >
> wrote:
>
>>> ...Add some turn signals, brake lights, etc, and that's it...
>>
>>Whatever the contraption, could you take it around an obstacle course?
>> To my knowledge there's only one tricycle CAR in the world (it's
>>British). There's a reason.
>
> Hmmm, a small ATV with a detachable powered chute? You won't get
> anywhere fast but a big enough chute might carry the thing.
>
> Corky Scott

Not quite what I had in mind, but check this out:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=63722&item=4525938698&rd=1&ssPageName=WDVW

Adam
N7966L
Beech Super III

[mindenpilot]

"Chris W" > wrote in message
news:0ILNd.1855$53.928@lakeread07...
> Just for fun, lets explore this idea some more. Obviously weight is the
> biggest problem or you could just mount a folding wing, tail feathers and
> prop to your Honda. The weight of a transmission to drive the wheels
> directly alone would probably add to much weight to be practical. So you
> suggested driving it with the prop with some kind of cage around it. If
> you are going to put a cage around the prop, you might as well make it
> useful. Make it a pusher prop with a ducted fan instead of a normal
> simple prop. I think some home builder is working on a design like that.
> Second have you ever noticed how amazingly horrible the ground handling of
> every airplane I have ever seen is? To make it road worthy, even if just
> for non-highway use, you would have to have a more car like suspension.
> That of course is going to add a significant amount of weight to the
> machine. One of the reasons airplanes are so unstable on the ground is,
> by necessity the main wheels need to be pretty close to the CG. I'm not
> sure you could get good ground handling with out moving the main wheels
> further from the CG. Tires alone are going add a huge amount of weight,
> if you try and drive around on typical airplane tires you are going to be
> replacing them every time you turn around. Finally brakes, you are never
> going to drive a vehicle like this on the road with out a much better
> brake system than most airplanes have, and again that is going to add a
> lot of weight. As another poster so rudely put it, no you can't make up
> for weight with more horse power. Obviously it can and has been done, but
> I doubt you will ever see a flying car that can drive or fly very good at
> all.

I agree with all of your points.
Additionally, I think acceleration would be an issue.
If you were stopped at a red light, you might get some horns honked at you
unless you could start moving right away.
My plane has some lag before it starts moving.

It seems that we have identified about five areas to focus on:
1. propulsion (caged prop, pusher prop, ducted fan)
2. ground handling
3. tires
4. brakes
5. acceleration

I don't think this is a comprehensive list, but for the sake of argument,
let's say that it is.
The problem now becomes a whole lot more like engineering problem solving
than pie-in-the-sky.

I'll have to think about each of these a bit before trying to attempt
possible solutions, but now I have some things to think about.

Adam
N7966L
Beech Super III

[mindenpilot]

"Morgans" > wrote in message
...
>
> "Hank Rausch" > wrote in message
> oups.com...
>> Here's something like what you are looking for--a roadable vehicle that
>> can fly. It is a parachute conversion for a Honda Reflex motorcycle.
>>
>>
>>
>> http://www.ultralightnews.com/airventure2001/flitebike.htm
>>
>
> Except he could easily do the trip twice as fast in a car, as with a
> parachute and motorcycle. The wind limitations of a powered chute could
> eliminate 50% or more of the days that would otherwise be flyable.
> --
> Jim in NC
>
>

That is absolutely true.
However, it won't stop one person who actually *wants* to do it.
How else could you explain people who pay money to glide, or do hang-glide,
etc.
Even though this technology is not what I was envisioning, it's a start, and
it may or may not evolve.

If someone came up with some extremely inefficient vehicle that does what
I've proposed, *I* would probably try it.
And, it would probably be improved upon as time went on.
This is a LOOONG way from not being possible.

Adam
N7966L
Beech Super III

[Morgans]

"mindenpilot" > wrote

> Not quite what I had in mind, but check this out:
>
>
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=63722&item=4525938698&rd=1&ssPageName=WDVW

Just curious, but did you notice the cruise speed, and the maximum wind
speed at launch time?
--
Jim in NC

[[email protected]]

> I bet more than one reader of this group (maybe the homebuilt group)
could
>hack something together in no time.
>It would then be reasonably easy to get it certified as experimental.
>What about certified to drive on the road?
>Keep in mind the golf carts that are road legal...

I've been in the homebuilding world since 1973 and can think
of a half-dozen attempts to build a roadable car. NONE of them were
worth pursuing. They were heavy, flew rather poorly and most were
rotten as cars. Some of them killed their designers. The added
mechanism to gear an engine to wheels adds a lot of weight any way you
look at it, and the engine, if it's aircooled, has to have a fan. More
weight. The cumbersome wings and tail take time to remove and install,
and a simple mistake in assembly can kill. There was one, a delta sort
of layout, that had folding wings that bent twice and shielded the
pusher prop. More heavy mechanisms. IIRC the designer couldn't get any
road licensing with that prop driving the "car." Too dangerous. Imagine
the reaction of an insurance company! Another one, a Ford Pinto married
to the aft section of a Cessna 337, actually flew. The airplane section
was unbolted and left at the airport while the car ran around town. The
whole thing was too heavy, and one day the car fell off in flight. End
of experiment.
People with big ideas about building flying cars should do
their research and learn a lot before trying to persuade someone that
it's easy. There have been many mistakes make and the ignorant will
only make them again. The simple fact is that airplanes are meant to
fly and cars are meant to drive, and because of the technological
requirements the two don't fit together well in one machine at all.

Dan

[mindenpilot]

"Morgans" > wrote in message
...
>
> "mindenpilot" > wrote
>
>> Not quite what I had in mind, but check this out:
>>
>>
> http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=63722&item=4525938698&rd=1&ssPageName=WDVW
>
> Just curious, but did you notice the cruise speed, and the maximum wind
> speed at launch time?
> --
> Jim in NC
>
>

Yes. Did you see my response to your other post about max speed, etc?
People aren't going to do it because it's fast or efficient.
If that were true, I wouldn't even fly my plane.
Ninety percent of the trips I take would be cheaper if I drove or flew
commercial.
I do it because I *want* to do it.

Adam

[Morgans]

"mindenpilot" > wrote
>
> It seems that we have identified about five areas to focus on:
> 1. propulsion (caged prop, pusher prop, ducted fan)
> 2. ground handling
> 3. tires
> 4. brakes
> 5. acceleration

>
> I'll have to think about each of these a bit before trying to attempt
> possible solutions, but now I have some things to think about.
>
> Adam

Eliminate the moving prop, as thrust for ground propulsion. Doing so will
solve the acceleration problem. The dust it would throw up will make it
very unpopular, if not outlawed. The guard would have to have bars close
enough together to keep even a finger from getting into it, and most likely
even hair. I don't have my OSHA book with me, but I'm certain the regs on
the guard are very restrictive, and will keep the prop from being used on
the ground. *If* you got around the problems of using the prop on the
ground, the airflow restriction would be high enough to make it unusable for
air propulsion.
--
Jim in NC

[Morgans]

"mindenpilot" > wrote

> Yes. Did you see my response to your other post about max speed, etc?
> People aren't going to do it because it's fast or efficient.
> If that were true, I wouldn't even fly my plane.
> Ninety percent of the trips I take would be cheaper if I drove or flew
> commercial.
> I do it because I *want* to do it.
>
> Adam

I was sure that the original proposal was to fly the first part of a trip,
then drive the rest, to make it possible to save time (AND enjoy) commuting.
No?
--
Jim in NC

[mindenpilot]

"Morgans" > wrote in message
...
>
> "mindenpilot" > wrote
>
>> Yes. Did you see my response to your other post about max speed, etc?
>> People aren't going to do it because it's fast or efficient.
>> If that were true, I wouldn't even fly my plane.
>> Ninety percent of the trips I take would be cheaper if I drove or flew
>> commercial.
>> I do it because I *want* to do it.
>>
>> Adam
>
> I was sure that the original proposal was to fly the first part of a trip,
> then drive the rest, to make it possible to save time (AND enjoy)
> commuting.
> No?
> --
> Jim in NC
>
>

Yes.
Saving time would be nice.
Independence (not relying on a taxi, etc) is the key factor for me.
Still being able to fly, but then after landing, still being PIC of my craft
would simply be cool.
Being able to go anywhere I want, whenever I want, without relying on anyone
else... that's my personal goal.
Flying *almost* gets me that.
That's why I originally made the post.

I've been looking at some designs out there.
Some are complete crap.
Others seem feasible.
I don't believe for a minute that it is not technically possible.
Some big problems areas have been raised.
Like most problems, though, it will be solved if someone throws enough money
at it.


Adam
N7966L
Beech Super III

[mindenpilot]

"Morgans" > wrote in message
...
>
> "mindenpilot" > wrote
>>
>> It seems that we have identified about five areas to focus on:
>> 1. propulsion (caged prop, pusher prop, ducted fan)
>> 2. ground handling
>> 3. tires
>> 4. brakes
>> 5. acceleration
>
>>
>> I'll have to think about each of these a bit before trying to attempt
>> possible solutions, but now I have some things to think about.
>>
>> Adam
>
> Eliminate the moving prop, as thrust for ground propulsion. Doing so will
> solve the acceleration problem. The dust it would throw up will make it
> very unpopular, if not outlawed. The guard would have to have bars close
> enough together to keep even a finger from getting into it, and most
> likely
> even hair. I don't have my OSHA book with me, but I'm certain the regs on
> the guard are very restrictive, and will keep the prop from being used on
> the ground. *If* you got around the problems of using the prop on the
> ground, the airflow restriction would be high enough to make it unusable
> for
> air propulsion.
> --
> Jim in NC
>
>

Again, you're right. Some of the more feasible designs I've seen use a
secondary method of propulsion while on the ground. This seems to be the
way to go. You're starting to sound like a believer ;-)

Adam
N7966L
Beech Super III

[Morgans]

"mindenpilot" > wrote

> Again, you're right. Some of the more feasible designs I've seen use a
> secondary method of propulsion while on the ground. This seems to be the
> way to go.

> You're starting to sound like a believer ;-)
>
> Adam

Nope. Once you are headed down the only road to do it, you will start to
understand the huge obsticales in your way. The weight to make it road
worthy will kill its chances of flying well. (or at all)
--
Jim in NC

[mindenpilot]

"Morgans" > wrote in message
...
>
> "mindenpilot" > wrote
>
>> Again, you're right. Some of the more feasible designs I've seen use a
>> secondary method of propulsion while on the ground. This seems to be the
>> way to go.
>
>> You're starting to sound like a believer ;-)
>>
>> Adam
>
> Nope. Once you are headed down the only road to do it, you will start to
> understand the huge obsticales in your way. The weight to make it road
> worthy will kill its chances of flying well. (or at all)
> --
> Jim in NC
>
>

I'm wondering what it needs to be road worthy that will be so heavy.
I may be wrong, but I keep going back to the golf card theory.

Adam
N7966L
Beech Super III

[Chris W]

Morgans wrote:

>Eliminate the moving prop, as thrust for ground propulsion. Doing so will
>solve the acceleration problem. The dust it would throw up will make it
>very unpopular, if not outlawed. The guard would have to have bars close
>enough together to keep even a finger from getting into it, and most likely
>even hair.
>
I don't know, if you were to go the ducted fan route you could have the
inlet and outlet of the duct far enough from the prop that the guard
wouldn't have to be all that restrictive and it could be easily removed
for flight. Also the ducted fan would provide more thrust for the same
horsepower if I'm not mistaken. If it is a constant speed fan, I bet
you could get acceptable acceleration out of it. However the dust it
would throw up and noise would probably be big down side. You may be
able to minimize the dust problem by mounting the fan high on the
vehicle. But the noise would be pretty bad still.

I really don't like the idea of having 2 power plants but if you are
going to drive the wheels I don't see that there is a practical
alternative.... or wait.... maybe hydrostatic drive off the same drive
shaft as the prop. A lot of research is going into hydrostatic
transmissions these days. The can be pretty compact but are generally
heavy. Since you only want around town slow driving capability, maybe a
compact light weight engine with low gearing would fit the bill. If you
could make some use of that power plant during flight, so it wasn't
completely dead weight that would be nice..... maybe have it drive all
the engine accessories for flight and ground use.


--
Chris W

Gift Giving Made Easy
Get the gifts you want &
give the gifts they want
http://thewishzone.com

"They that can give up essential liberty
to obtain a little temporary safety
deserve neither liberty nor safety."
-- Benjamin Franklin, 1759 Historical Review of Pennsylvania

[Corky Scott]

On Mon, 7 Feb 2005 18:51:59 -0800, "mindenpilot"
> wrote:

>It seems that we have identified about five areas to focus on:
>1. propulsion (caged prop, pusher prop, ducted fan)
>2. ground handling
>3. tires
>4. brakes
>5. acceleration

Like others, I don't think using the prop for ground propulsion makes
sense. Too much danger in FOD, not to mention the noise factor and
the prop blast. Some kind of declutchable drive should be used and a
transmission. But this requires a driveshaft and differential as
well, unless some kind of engine driven generator is used to drive
perhaps on wheel with the rest of them non driven.

This brings up the possibility of a three wheeled vehical with the
driven wheel being the single wheel. It eliminates the need for the
differential, thus saving weight. But you'll still need some sort of
transmission.

Corky Scott

[Paul Sengupta]

"Morgans" > wrote in message
...
>
> "CryptWolf" > wrote
>
> > Most twins and some larger singles could handle the weight of
> > a motorcycle and perhaps even a passenger. Getting it through
> > the door might be a problem on many models.
>
> There you go! Much better solution than an aircar, made of unobtanium!
>
> Some of the small scooters are smaller, and lighter, which should help
> loading singlehanded.
>
> The way around the door size issue and the seats, ect, is to go
> experimental. You can do pretty much as you please, modification wise. A
> number of designs could handle the loading and weight requirements.

http://www.diblasi.com/

Paul

[Big John]

Don't laugh.

Anti Gravity has been demonstrated in the lab.

Long way from the market but remember when the transister first came
out and people said what can you do with that.

Big John
`````````````````````````````````````````````````` ``````````````````````````````

On Mon, 7 Feb 2005 08:35:09 -0800, "aluckyguess" > wrote:

>Anti-Gravity ?
>If there is a will there is a way. I think the only thing keeping it from
>happening is the cost. There is no way to make it cost efficient at this
>time.
>

[Peter Duniho]

"Big John" > wrote in message
...
> Don't laugh.
>
> Anti Gravity has been demonstrated in the lab.
>
> Long way from the market but remember when the transister first came
> out and people said what can you do with that.

No, they didn't. By the time the transistor had been invented, vacuum tube
had already been proven VERY useful in a wide variety of applications. A
transistor is just a very compact vacuum tube (minus the empty space, of
course :) ), at least in terms of function.

But even if that had been the case, the issue with anti-gravity isn't that
people say "what can you do with that?" I think pretty much everyone can
see lots of applications for anti-gravity. :) The real problem is that,
unlike the transistor, any theoretical demonstration of anti-gravity has
been in a context with no hope of real-world application.

The only real problem with a roadable airplane is practicality. Even cost
isn't insurmountable, since plenty of people spend plenty of money on plenty
of luxuries. There's obviously a size point at which a roadable car would
work; after all, in the worst case you just build an airplane large enough
to carry a car (which has already been done, of course).

The practicality problem comes in with respect to the fact that even people
who spend lots of money on luxuries don't like spending more money to solve
a problem than they really need to. And no matter what you do, it will
"always" be less expensive to hire a limo at your destination than to fly an
airplane that can turn into a limo at your destination. :) ("Always" in
quotes because, who knows?, maybe limos will get REALLY expensive some day).

Pete

[Kyler Laird]

"Morgans" > writes:


>"CryptWolf" > wrote

>> Most twins and some larger singles could handle the weight of
>> a motorcycle and perhaps even a passenger. Getting it through
>> the door might be a problem on many models.

>There you go! Much better solution than an aircar, made of unobtanium!

http://www.pilatus-aircraft.com/2_ga_commercial/images/img_interior_3.jpg

--kyler

[stuart]

This one has been solved. Dedicated equipment is the best and most
convenient. I have enough trouble getting an airplane, however a rental
car is pretty easy.

If you are just commuting, leave a beater at the airport.

I would start with a backpack powered parachute and a bicycle and work
your way up.

Stuart

mindenpilot wrote:
> OK, you have to humor me on this.
> I'm not talking about anything unrealistic (like Moller's skycar, etc).
> But what would prevent a design (even low performance/ultra light to start)
> that would allow a pilot to fly into an airport, then fold up his wings and
> cruise down surface streets at 45mph?
>
> It doesn't sound that complex. I bet a homebuilder could do it with parts
> laying around his garage.
> The only serious issue I can think of is having a spinning prop on a city
> street.
> Even so, couldn't you "disengage" the prop and then couple the engine to the
> mains somehow?
> I realize that is a bit more complex and would mean some kind of
> transmission.
> I'm just throwing out ideas here.
>
> It sure would be nice not to rent a car or get a taxi!
> It also seems that there would be a MUCH larger interest in GA if people
> could potentially commute this way.
> For example, I would consider working in Reno and living in Minden if I
> could fly into Reno, then commute to my work.
>
> I'm serious about this, but I'm ready for the flames ;-)
>
> Adam
> N7966L
> Beech Super III
>
>

[Montblack]

("stuart" wrote)
>> But what would prevent a design (even low performance/ultra light to
>> start) that would allow a pilot to fly into an airport, then fold up his
>> wings and cruise down surface streets at 45mph?

I would start with the car - assuming not a motorcycle. What is the lightest
car you can build, that is street legal, will fit your mission and can
cruise at 50 mph? From there design your plane around THAT.

http://www.goldenwingsmuseum.com/Aircraft%20Pages/Aero%20Car.html
http://www.goldenwingsmuseum.com/Photo's/Aero%20Car-2.jpg
At Golden Wings Museum: (ANE) Anoka-Blaine Airport, MN

Good luck.

Montblack

[Richard Thomas]

On Mon, 7 Feb 2005 18:14:33 -0800, "mindenpilot"
> wrote:

>Once more, I am not proposing anything pretty or elegant at first, just
>something that will work.
>Hell, a mini-MAX will work right now (aside from street-legal issues).
>It will fly, the wings come off in 10 minutes, then you could taxi it.
>
>Let's make it more elegant from there...

Motivation wise, you might consider an electric motor. Electric motors
have great torque all the way from the bottom so you could effectively
do away with a gearbox which would have been extra weight. For very
short distances, you could run it from the battery. Since you can't
afford the weight of a big battery pack, if you want to go a little
further, you would need to run the engine to keep it charged which
would mean you would need to be able to disconnect the prop. That
would either mean a clutch or perhaps removing the prop when you
remove the wings.

Something else that occurs to me is that the triangular arrangement of
the landing gear is (presumably) to somewhat absorb the impact of the
landing. Since this is not required on the road, you might want to be
able to widen the triangle to provide extra stability from a broader
wheelbase and a lower center of gravity. It might be possible to add
this without too much extra weight...

Rich

--
An animal so poor in spirit that he won't even fight on his own behalf
is already an evolutionary dead end; the best he can do for his breed
is crawl off and die, and not pass on his defective genes.
--R.A.Heinlein