Does anyone know what airfoil is used on the Mountain Goat?

Cool airplane. Saw a couple around lake hood.
http://www.bushplanes.com/specifications-and-performance.html

And an older thread on the cub site:
http://www.supercub.org/forum/archive/index.php/t-23076.html

aktahoe1,

thanks, I seen that thread and the web site. I guess my fundamental question is this; is there an airfoil that has as much lift but less drag (i.e. better lift to draft ratio) than the cub airfoil given the same wing area? In the years since the cub or taylor craft wing was designed a lot of work has gone in to airfoil design for gliders and other aircraft. I'm thinking if I were to build an experimental I might want to go with an improved airfoil shape.

I'm sure there are more modern airfoils that offer a better compromise between high-lift (but slow), and laminar flow-fast, (but marginal climb). While these two attributes seem to be diametrically opposed, there are compromises that should oughta work well.

The airfoil used in my Husky seems to have a fairly broad envelope, able to get into short strips (though not quite as short as a super cub) while delivering decent "high speed" cruise efficiency with the MT paddle turning slow <2000 rpm, 55%, and 5.5 gph, it purrs along at 103 - 105 knots w/26" rubber.

aktahoe1 wrote:Cool airplane. Saw a couple around lake hood.
http://www.bushplanes.com/specifications-and-performance.html

And an older thread on the cub site:
http://www.supercub.org/forum/archive/index.php/t-23076.html

Actually, there has only been one of them, and it was wrecked a while back. He made a lot of noise about the airplane, but it's performance was no better than a cub, if that good.

MTV

MTV,
Actually I think there were at least one or two others built. If I remember correctly it is in PA. Don't quote me on that but I remember corresponding with the owner at one time.
Found it! http://shellenberger.net/goatworks/mtngoat2.htm
It is named on its registration as: Goat Works Inc and its in Sharon, PA.
Not sure if it is still flying or not but the owner at the time had good things to say about it.
Keith

While we are on that subject, let me sorta hijack the thread for a bit.
The Riblet wing (airfoil) which is promoted as the cat's meow in this area?
True/not true? Feedback please?

lc

yea, DE which uses the Ribblet airfoil says it has a camber on the bottom which give more lift than the cub airfoil but may lose a couple miles per hour in cruise. That does not seem to be a hugh difference.

I flew in a pipistrel trainer and was impressed by the performance of a 80hp light sport. with 1000lbs we got off the ground in 300ft, stall was 35 knts and cruise was a legitimate 120mph. It got me thinking about airfoils, etc.

Don't think you'll find what you're after in the glider realm, as that's a whole different ball game.

I have and ASH26E (50 to 1) self-launch. And while it only has 50 hp, it has a span of 59 feet, and of course a high aspect ratio wing. At 5 - 8K density altitudes I'm seeing not much more that 400 fps climb with the engine during launch. Like most modern gliders, the wing is optimized for minimum drag, minimum sink, and best L/D in a band of about 50 to 60 knots, while trying to preserve a decent L/D at higher speeds (90 knots, where L/D falls of to maybe 30 to 35).

Schleicher goes overboard in trying to keep flow attached, with amazingly smooth wing surfaces and little blow holes to keep flow attached under the wing etc.

The span alone precludes any serious consideration of this sort of wing for back country use, and if one were to simply make it shorter, wing loading would go way the heck up.

For out purposes shorter wide cord (hawks and eagles) is better than long and narrow (albatross).

WWhunter wrote:MTV,
Actually I think there were at least one or two others built. If I remember correctly it is in PA. Don't quote me on that but I remember corresponding with the owner at one time.
Found it! http://shellenberger.net/goatworks/mtngoat2.htm
It is named on its registration as: Goat Works Inc and its in Sharon, PA.
Not sure if it is still flying or not but the owner at the time had good things to say about it.
Keith

Keith,

You're right. I'd forgot that Montaigne sold a "kit" to that gent. The "prototype " wore a few different wings and other features over the years, but I believe that was the only one he built.

That airplane was around for a few years, and I don't know anyone who saw it fly who was very impressed with performance, thou it did okay, but no better than a lot of other planes.

MTV

MTV- am I wrong by saying this aircraft looks very much like a Rans 7s? Lpoking through my photos and could swear there was a blue and white at lake hood maybe 10 years ago or so. I remember my pops bagging on it and talking about how the maker was an ass. Don't want to add speculation. Did the company ever get off the ground?

aktahoe1 wrote:MTV- am I wrong by saying this aircraft looks very much like a Rans 7s? Lpoking through my photos and could swear there was a blue and white at lake hood maybe 10 years ago or so. I remember my pops bagging on it and talking about how the maker was an ass. Don't want to add speculation. Did the company ever get off the ground?

aktahoe, Listen to your pops.
This thread from Jan. 2011 viewtopic.php?f=47&t=6757&p=86986&hilit=dirtstrip+mountain+goat#p86986

dirtstrip wrote:

EZFlap wrote:

dirtstrip wrote:
The two seater of my dreams was the Montaigne Mountain Goat STOL.
Specs and performance here. http://www.bushplanes.com/specification ... mance.html Unfortunately not in production yet.

IMHO do not hand any money over to Bill Montagne, and whatever you do definitely do not fly in or behind anything he builds until you have been physically present at a structural load test ! If you go to a load test, stand outside the test cell. If the load test is in an engine test cell, stand outside the county line.

I apologize for hijacking this thread. I have first-hand experience with this guy maneuvering for money, and I have second-hand knowledge of his workmanship having the potential to hurt somebody. If the forum admin. specifically allows it I will offer an explanation.

I never pursued the 2 place dream. My requirements were for a four place. In my posts to this topic I have been careful to recommend checking out company support, present customers and flying the plane, and not to fall for the company specs of a plane because in dream shopping thats where many start and thats all the farther I got with this one. Got to admit it is seductive in the numbers. Thanks for the Dangerous Undertow Warning. The waters looked good on the surface.

Not to put too fine a point on it, but the guy has mentioned in a few places he invested 'million$' in the design and development of the plane, along with some other real quotable gems, like improving the L/D ratio by a factor of 4 ("...half the drag, while doubling the lift...").

Sounds like you're looking for a Kitfox.

Ribblet airfoil, 30 kt stall, 110 kt cruise, 80 hp Rotax sipping 3gph. Mine weighs 650# so under lsa rules I have a 670# usefull load...

Littlecub wrote:While we are on that subject, let me sorta hijack the thread for a bit.
The Riblet wing (airfoil) which is promoted as the cat's meow in this area?
True/not true? Feedback please?

lc

Av8r3400 wrote:Sounds like you're looking for a Kitfox.

Ribblet airfoil, 30 kt stall, 110 kt cruise, 80 hp Rotax sipping 3gph. Mine weighs 650# so under lsa rules I have a 670# usefull load...

The Dream Aircraft Tundra is a four place and uses a modified Riblett 660.15 airfoil. It has an under camber to the lower wing skin. 1450 empty 2550 max takeoff. With full Fowler flaps mine stalls a little over 30 mph well mannered, but with a high sink rate, cruise 120 fixed prop or 140 constant speed. Takes off and lands both in 400 ft. I don't know if the Riblett airfoils are any better than NACA but in the right crowd they sure cause a lot of discussion. To the best of my knowledge the Riblett airfoils seem to be found only on experimentals.

aktahoe1 wrote:MTV- am I wrong by saying this aircraft looks very much like a Rans 7s? Lpoking through my photos and could swear there was a blue and white at lake hood maybe 10 years ago or so. I remember my pops bagging on it and talking about how the maker was an ass. Don't want to add speculation. Did the company ever get off the ground?

He undoubtely had the prototype at LHD at various times.

And, always listen to your father.

MTV