Folding wings

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

"Morgans" wrote in message
...

"mindenpilot" wrote

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


http://cgi.ebay.com/ebaymotors/ws/eB...sPageName=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

"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

"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

"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

"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

"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

"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

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

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