FAR rules on "ground-effect" vehicles?

Does anyone here know if / what-section-of FAR rules govern the operation of
"ground effect" vehicles? Specifically, how high can a machine fly AGL before
its technically classified as an aircraft and not a hovercraft,
hydroplane-boat, Ecronoplan, etc.? Is there a loophole for a powered airplane
that can't climb to more than 5' AGL?

Second question: If a machine has tricycle gear with nosewheel steering, wings
and 3-axis control, and is solely propelled by thrust from an engine/propeller,
BUT CANNOT FLY, how is it classified? Trike motorcycle?

NOTE: Both of these questions relate to a proposed machine that will weigh
more than 254lbs dry, i.e. not Part 103 legal.

Serious responses please. I'm looking to find and verify a specific FAR rule,
as the correct answer to this question is critical for legal, operational, and
insurance purposes.

Thanks,
Harry Frey
Wright Brothers Enterprises

Does anyone here know if / what-section-of FAR rules govern the operation of
"ground effect" vehicles? Specifically, how high can a machine fly AGL
before
its technically classified as an aircraft and not a hovercraft,
hydroplane-boat, Ecronoplan, etc.? Is there a loophole for a powered
airplane
that can't climb to more than 5' AGL?

Second question: If a machine has tricycle gear with nosewheel steering,
wings
and 3-axis control, and is solely propelled by thrust from an
engine/propeller,
BUT CANNOT FLY, how is it classified? Trike motorcycle?

NOTE: Both of these questions relate to a proposed machine that will weigh
more than 254lbs dry, i.e. not Part 103 legal.

Serious responses please. I'm looking to find and verify a specific FAR
rule,
as the correct answer to this question is critical for legal, operational,
and
insurance purposes.

Thanks,
Harry Frey
Wright Brothers Enterprises



Do an internet search on hovercrafts, WIG, Wing in Ground effect etc etc....

I dont remember the exact sites, but IIRC as long as it CANNOT get and stay out
of ground effect, ie KEEP gaining altitude...it AINT an aircraft...and it can
wiegh what ever you want....though its still a good idea to keep it
light.....(though high hops that utilize the vehicles kinetic engery, trading
off temporary altitude for speed are allowed)....its considered an ocean going
vessel and you actually have/should register it with the coast guard....and if
you do you'll probably be one of only a handful of people on the planet that
has such a registration.....

Now if you fly it over land I have no idea who you talk too....but besides
Groom lake i dont have a clue where youd fly such a thing over land....

here is one site I happen to have:

http://www.se-technology.com/wig/index.php

take care

Blll

On 01 Apr 2004 22:57:17 GMT,
(Wright1902Glider) wrote:

Does anyone here know if / what-section-of FAR rules govern the operation of
"ground effect" vehicles? Specifically, how high can a machine fly AGL before
its technically classified as an aircraft and not a hovercraft,
hydroplane-boat, Ecronoplan, etc.? Is there a loophole for a powered airplane
that can't climb to more than 5' AGL?

Second question: If a machine has tricycle gear with nosewheel steering, wings
and 3-axis control, and is solely propelled by thrust from an engine/propeller,
BUT CANNOT FLY, how is it classified? Trike motorcycle?

NOTE: Both of these questions relate to a proposed machine that will weigh
more than 254lbs dry, i.e. not Part 103 legal.

Serious responses please. I'm looking to find and verify a specific FAR rule,
as the correct answer to this question is critical for legal, operational, and
insurance purposes.

It can't fly the FAA doesn't care, however your state and local regs
most likely will. That varies widely from state to state.

In Michigan it could be a nightmare if you operate on land and water
as it'd most likely be considered an all terrain vehicle (ATV)
requiring state stickers if used off your own land AND it would
probably require registering as a water craft if operated on water
AND then there would be operating in and along the edges of the Great
Lakes which requires additional schooling/training for the
operator(s).

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com


Thanks,
Harry Frey
Wright Brothers Enterprises

Hi,

found a few old WIG links last night....

these have pics of WIG hovercraft flying....

http://popularmechanics.com/outdoors...ts/print.phtml

http://www.hovercraft.com/

http://www.se-technology.com/wig/index.php


I used to have one pic showing a WIG hovercraft about 10 feet above the ground
doing a "hop"....bet it felt like a hundred feet to the operator though!

WIG hovercraft appear to have many problems....airborne stability for
one....another, dealing with mirror contacts with ground or water (waves)
without it turning into something resembling that bad landing they used to show
at the begining of the 6 million dollar man episodes....

Another problem is variation of weight.....you need to make sure you CANT get
truelly "aircraft" airborne at minimum load, yet you still want to be a decent
height above the surface at maximum load....so it may make more sense to NOT
make the thing as light as possible as you would an aircraft....so that the
percentage difference between min load and max load is significantly smaller
than that of a true typical aircraft....

which aint neccessarily bad...becuase if I built one of those suckers I'd put
in a heavy duty roll cage that protected me, my neck, and ensured that I
floated upright and intact when (not if) I wrecked the thing and it ripped
apart in spectacular fashion!

Sure, that way the drag is more than if you made it as light as possible, BUT I
bet you would still be going alot faster with much less energy than you would
in an equivalent boat! And the ride would be smoother...at least until you
crashed....

The CD reduction is .8 at height = .25 wing size, .6 at .15, and .5 at .10 the
wing size...where IIRC size = chord...though it could be span....and at height
above ground effect CD = 1.0

So you can see you need to get pretty close to the ground for the WIG effect to
help much...

I'll email you the graph I have

take care

Blll

Let me make a clarification to my original post:

The machine that I'm considering is NOT GOING TO OPERATE FROM/OVER WATER. It
is not a flying-boat / hydroplane / Skycar / UFO thingie. It was designed as a
land-based aircraft and looks something like an untralight. It had wheeled
landing gear, wings, control surfaces, engine & prop, etc. However, it never
flew very well or very far... if it ever flew at all. There is no photographic
proof that it ever could or did leave the ground. Eyewitness reports lead me
to believe that it never flew out of ground effect, and never flew more than a
few hundred yards before being retired.

Now here's the rub: all of the flying Wright 1903 Flyer replacas that I know
of are considered (and are) true aircraft, thus requiring a PPL, N-numbers,
etc. They rely on sound aerodyamic principles and would be capable of flying
for miles at altitudes in excess of 10' AGL, given a very good pilot.

The machine that I'm researching does not benefit from any sort of aerodynamic
wing design. Its ribs are flat. If it flew, it was because large ammounts of
power were used to shove it into the air for a few hundred feet.

SO, is there a difference in the eyes of the FAA? And if so, what part of FAR
would govern such a machine? I realize this is a very unusual question, thanks
for your help.

Harry

SO, is there a difference in the eyes of the FAA? And if so, what part of
FAR
would govern such a machine? I realize this is a very unusual question,
thanks
for your help.

Harry

If it doesnt fly why should the FAA give a hoot?

The FAA doesnt regulate hovercraft or airboats and those use airprops for
forward propulsion...


Of course I dont know diddly about FAA regs either...

I hope you have some smoothhhh, softffff ground and that you are going pretty
darn slow when you do your flight tests at 3 ft AGL....

take care

Blll

Bill,

I was hoping that the FAA already had a rule or subsection on the books
governing WIG's. That way I could redesign the aircraft I'm considering so
that it would meet the rule. Unfortunately, it looks like the FAA has never
addressed this subject. However, they were adament about regulating ALL of the
reproduction Wright Flyers built last year. Even though the flight envelope of
those craft are very similar to the one I'm considering.

Since I do not currently have a PPL, clasifing the aircraft experimental is not
really an option. It might still be possible to go Part 103, but that won't be
easy. Right now my calculations put the plane at least 100 lbs. overweight.
This is the case for most turn-of-the-century aircraft. They are too slow and
primative to fly like modern airplanes, yet too heavy to be considered
ultralights. So far, I've managed to avoid the FAA problem by building kites
and gliders. But having to wing-walk / push my glider 7 miles around an
airfield last year convinced me that I want power on the next plane I build.

If anybody does happen to find an FAA subsection that specifically mentions
WIG's, please let me know.

Thanks for your input,
Harry

(BllFs6) wrote in message ...
Hi,

found a few old WIG links last night....

these have pics of WIG hovercraft flying....

http://popularmechanics.com/outdoors...ts/print.phtml

http://www.hovercraft.com/

http://www.se-technology.com/wig/index.php


I used to have one pic showing a WIG hovercraft about 10 feet above the ground
doing a "hop"....bet it felt like a hundred feet to the operator though!

WIG hovercraft appear to have many problems....airborne stability for
one....another, dealing with mirror contacts with ground or water (waves)
without it turning into something resembling that bad landing they used to show
at the begining of the 6 million dollar man episodes....


I am not an expert on this topic but I have seen WIG hovercraft in
operation and talked to their designers.
The idea behind this design is that the aircushion makes final
break-away from the surface easy, with very little drag at the
transition. Also, touch down is very smooth.
As for wing tip contacts with water, it does not seem to be very
upsetting. The tip shapes dictate that the contact is only with the
trailing edge.
These things are cool to watch but they are mostly just a stunt,
in my humble opinion because they are slower than the hovercraft they
are derived from. Plus, they are naturally more wind-sensitive than a
hovercraft.
One reason that the hovercraft community keeps looking at WIG
technology is that light hovercraft start to fly away from dynamic
lift effects around 55-65 mph. That has been an upper speed limit,
unless one is willing to pile on weight. High performance hovercraft
can accelerate to 60 mph from a dead stop in under 10 seconds (
precise measurement is nearly impossible. Maybe with a calibrated
video camera)
That performance comes from having static nearly equal to empty
weight.


Another problem is variation of weight.....you need to make sure you CANT get
truelly "aircraft" airborne at minimum load, yet you still want to be a decent
height above the surface at maximum load....so it may make more sense to NOT
make the thing as light as possible as you would an aircraft....so that the
percentage difference between min load and max load is significantly smaller
than that of a true typical aircraft....

which aint neccessarily bad...becuase if I built one of those suckers I'd put
in a heavy duty roll cage that protected me, my neck, and ensured that I
floated upright and intact when (not if) I wrecked the thing and it ripped
apart in spectacular fashion!

Sure, that way the drag is more than if you made it as light as possible, BUT I
bet you would still be going alot faster with much less energy than you would
in an equivalent boat! And the ride would be smoother...at least until you
crashed....

The CD reduction is .8 at height = .25 wing size, .6 at .15, and .5 at .10 the
wing size...where IIRC size = chord...though it could be span....and at height
above ground effect CD = 1.0

So you can see you need to get pretty close to the ground for the WIG effect to
help much...

I'll email you the graph I have

take care

Blll

WELL, this certainly has turned out to be an interesting thread...

Let me make a few more clarifications:

First, I was not trying to infer anything about a Wright 1903 or later machine.
Not the point... not even close. 1903's, 1904's 1905's, etc are definately and
emphatically airplanes.

Second, the original "flying machine" that I am thinking about reproducing was
built in 1907. At best, a reproduction would be limited to straight-line
demonstration hops of less than 1,000 linear feet down a runway, closed road,
cow pasture, etc.

Third, I was reminded not so long ago that the original designer's son asked me
not to try to fly an accurate reproduction of this machine if I ever built one.

Therefore, I think I have found my angle... Its got 3 wheels, it does not use
public roads, and it will not fly. Therefore, it SHOULD be possible to
classify it as an ATV, rather than an aircraft, even though it does have
"wings". That takes 1/2 of the fun out of it, but maybe I could compensate by
making the engine louder or something.

Sorry that this thread wandered so far off-topic.

Harry

(Wright1902Glider) wrote in message ...
WELL, this certainly has turned out to be an interesting thread...

...

Therefore, I think I have found my angle... Its got 3 wheels, it does not use
public roads, and it will not fly. Therefore, it SHOULD be possible to
classify it as an ATV, rather than an aircraft, even though it does have
"wings". That takes 1/2 of the fun out of it, but maybe I could compensate by
making the engine louder or something.


Well if you find out that your state regs on ATVs are too burdensome
then maybe you can get the FAA to classify it as an experimental.
It surely won't be the first experimental aircraft to not get out
of ground effect. I'm sure lots never got off the ground at all.

--

FF