is it someone deep out there in the country that got some news about STOL-Stinsons modifications?

I HAVE A BRAND NEW AEROMATIC PROP SETTING AT MY A&P's SHOP SOON TO BE PUT ON MY PA18-95, CAME FROM TARVER'S PROPELLERS INC. FOR INFO. GO TO WWW.AEROMATIC.COM

Hi Everyone ;

I am considering buying a run out 108-3 and then doing a resore to it and convert to the super stinson technology with an 0-470 engine ?

I wanted to ask you guys if you can steer me in the right direction and give me some insight into the do's & don't's of a project like this undertaking ?

I have been a pilot since 1988 and although I have limited A/p knowledge .... I do know my way around a wrench and shop ?

let me hear what you think ?

Best holiday Wishes ,
Mike

Stinsoner,

If you believe the "percent reduction in stall speeds" that Micro puts out in their advertising, I have a really nice bridge I'd be willing to sell you as well .

Call Micro, and ask them specifically how they verified those data to the FAA for certification, and if indeed those numbers have been flight tested and verified, why do they not require re-marking of your airspeed indicator???

Those numbers are sales pitches, pure and simple.

MTV

I own a Stinson 108-3 and fly it almost exculsively off airport - wheels and floats. Mine has the 220HP Franklin and and 84 inch Hartzell CS prop. You do not need to do anything to this aircraft to make it STOL. I would not bother with vg's. The leading edge slats from the factory give you terrific aileraon controll all the way through the stall. Once you have some horsepower in a Stinson, and don't fill it up with all kinds of avionics and other heavy junk, the only thing that will make it a better STOL aircraft is the pilot and lots of practice. These birds will land and takeoff in very short distances, even with a good load in them. As for rebuilding, I would probably not put the 0470 in a Stinson. While they give great power, they are also heavy and need more fuel. In the Stinson application they add about 115 pounds of weight on the nose, as compared to the 220 Franklin or the IO 360 Continental (210 hp). The mandras tips- from all accounts I've read from people that have installed them- are an absolute nightmare to install, and don't do much for you. Honestly, these planes will fly and land very slow. I'm touching down at 45 mph with a decent load. They will also take off in a few hundred feet with the big motors. Slow speed handling is great. The big flaps would be impossible to get approved anymore, and honestly, a Stinson comes down like a rock when you shut off the power, so I don't see the need. Maybe some bigger tires - 8.50's just to get prop clearance. Otherwise don't mess with it, just fly it and get good at it. These planes are way more capable than 90% of the pilots that fly them. Stinson got it right the first time.

Found this on Barnstormers
http://www.barnstormers.com/classified_ ... Specs1.doc

I think this will still require some work, but a lot less headaches
than doing a complete engine conversion.

If I were going to go with a Cont O-470, I'd
use a runout to do the conversion and get the paperwork
completed and then send it to PPONK for conversion to
there O-470-50 Super Eagle.
http://www.pponk.com/HTML%20PAGES/O470_conversion.html

Thats a whole lot of money eihter way

What mtv said!

Rhyppa wrote:......Otherwise don't mess with it, just fly it and get good at it. These planes are way more capable than 90% of the pilots that fly them. Stinson got it right the first time.

This is true of a lot of airplanes, most are more STOL-able than the pilots flying them. ( Present company excluded of course. )

Go on the international stinson website and you will find all the info you need to make a decision. You can also try Hangar 9 aeroworks website. The gentleman who runs it is absolutley fanatical about gathering information on stinsons. I have a '46 108-1 with the 150 franklin and always have a ball in it. If the parts weren't so hard to get I'd put a 220 frank in mine when overhaul time came around. There are stc's for engines from 180 hp all the way up to 300, both lycoming and continental. As mentioned before, engine weight does become a factor. Lead has to be added to the tail posts on some of these mods. The battery and the engine mounts have to be redone. I also agree that VG"S seem to be a bit redundant for these planes. You have full aileron control down through stall. I bought mine with a climb prop on it and that thing could climb out of a shoe box if it was lightly loaded.
Good luck and have fun
Mark and the yellow stinson

Hi again over there!

Well, after reading all this it will be no Vortex-generators on my wings. For sure.

Instead I starting to make a good decision about the prop; its a wooden prop 74/56 in the front of a IO-360 (180 hp).

The cruise is very good, about 120 mph with full trottle, but I prefer to fly short, low and slow. So what kind of a prop would be the best buy when it comes to a very short take off distance?

/the stinsoner, still in

A climb prop on stinson should run static rmp of up to 2500, my md7456 run the bare minimum 2350 (PS YOU MUST CHECK WITH AN OPTICAL TACH THERE ORIGINALS ARE USUALLY HORRIFICALLY OFF) If you took it down to a 52 I belive this will give you close to 2500 static as per the stinson type certificate. I want a 49 degree prop as to use on floats with my 165 thought it might be to much and over spin. I do have the vg's however I have not installed them yet. On the stinson web site most who have the vg's agree that they make a significant difference when in a conventional gear taxi and takeoff position which is what vg's are supposed to do at those angles of attack it makes the airflow separation stick to the wing vs deflecting off the leading edge, I will let you know how I like the vg's once I get them on.

Mike

I had a sensinich 76CG53 on my stinson when I first got it. The redline for the engine is 2650. I had to keep a close eye on it to keep from pegging it on takeoff. I like the wooden prop especially for franklins since metal props cause a harmonic vibration between 2100 and 2300 RPM. And they look cool too. I have a falcon mid-range wooden prop on right now and it gets me 15-20 more mph in cruise with only about 100-200 more feet of takeoff roll. Falcon is not in business anymore and this particular prop is in limbo. It is an Olle Phalen design and has gone through several owners. If you can find one they need to be inspected pretty well. I don't have the specs for it here but if you're interested I could look it up. Look up bobcat conversions out of Oregon. They have a pretty good system for converting to 180 lycomings. They're getting some very impressive numbers with their setup.
Good luck
Mark and the yellow stinson

Hi , yes your right you have a great airplane. Why add mods one may ask. Why fix what is not broke? When it comes to mods you can make a great airplane better. One is to add more power. The reason for this is to climb faster then the train. Get out of a tight space and increase cargo payload. Alot of people will tell you once you add power you also add in fuel burn. That is true, but remember Time + speed = distance. A 165 hp. Franklin will burn more fuel then a 0470 in a 230 power motor. Another is to add the drop tips if one can find them. They add in the stability of the plane and increase lift. Another is to add the Vortex generators ( VGs) This adds in to reducing the stall speeds and to increase lift. All of this dose add in to making a great plane , even better. Another is to increase the size of the flaps. This is something that is helping to increase lift on takeoff and also to reduce speed on landing.. Here in Alaska I have a Stinson and have all of the mods mentioned. My plane is one that will not stall. So when someone says they dont help, they are quite wrong. It all adds up. Befor one dose the mods, you need to ask your self what kind of flying are you going to do... I also have the 31 inch Alaska Bush wheeles.. Happy flying and be safe.

If you want the pilot to be able to get more STOL performance out of the Stinson airplane, with a greater amount of safety at the same time, contact me offline or via private message.

stinsoner wrote:Hi friends!

Ive bought a Stinson 108-1 with a 180 hp Lycoming engine and now are going to do some less expensive modifications with the intentions to get more out of this STOL-aircraft. (Ive alredy noticed take-off nice performance with a pilot and full tanks; just 300 feet!
I think the Micro Aerodynamics vortex generator kit would be nice, but what more is possible to do?
Ive heard in the past about some wing-tip installation, but its not in production any more? What about flap-gap sealing? Would a carbon prop be better? 3-blades? Bigger is better? Etc.

regards
the stinsoner in Sweden

Stinsons in there STOCK form are pretty capable "Stol birds" .Stinson 108's were designed in the 1940's as personal transportation for 4 or less souls into or from cow pastures. We didn't have these massive concrete runways with flashing neon lights --- just some old dirt cleared off pasture .The idea of more power is ok but it's the wing that carries the load >> 108's have a GREAT wing with those slots .Never mind getting VG's .The only thing VG' do for your airplane is make it easier and positive CONTROL at lower airspeeds. 165-180 hp Franklin (or Lyc) is more than enough to launch out of your nearest open field. Madras (Ace Demers ) droop tips help a lot . I've seen 0-470's as well asO-540's being used. Aeromatic Props are
great for 180 hp birds. The weights for stock 108's are light and carry as much as a 180 Cessna . Controls are light and smooth -- " Cadillac of the air ". AZ50 has a whole flock of
108's flying .I go there once or twice a week to see whats happening and fly .

182 STOL driver wrote:....
.Never mind getting VG's .The only thing VG' do for your airplane is make it easier and positive CONTROL at lower airspeeds. ..... .

Yeah, who would want more positive control at low speed? That was the whole idea behind the original Micro VG kits for twins: lower single engine Vmc. As for STOL, it's hard to make a slow short landing in other than perfectly calm conditions if your airplane responds sluggishly to control imputs. That's why I'm considering adding VG's, for better low-speed control -- any reduction in stall speed is strictly a bonus.
But as far as a Stinson goes, isn't the slotted leading edge supposed to do the same thing as VG's-- keep airflow attached for better control authority and (maybe) lower stall speed? Seems like slots AND vg's are like a belt & suspenders- ya should only need one or the other, not both.

Eric

"There's no substitute for cubic inches", or, "ther's no replacement for displacement". I've seen 108's modified with O-360 and IO-360 Lyc's, 220 Franklins, 470 Continentals, & 540 Lyc's-- it seems like the 6-cylinder, 210 horse IO-360 Cont does as well as any of them, is relatively light for the horsepower, and smooth-running. One drawback is that it's not approved for cargas-- that may or may not be a moot point for you, or for all of us soon for that matter, but it is a valid point for me at this time.
A cheaper but effective alternative to a bigger engine may be proper wing & control rigging, an airplane weight-loss program, a bigger and/or flatter prop,and some simple mods like aileron/elevator gap seals (if applicable) and things like that.

Eric

Eric.

I just added VG's two weeks ago to my 108-2 and the increased aileron control was very noticeable. The slats help, but adding the VG's helped as well. I can fly comfortably around at 45mph and there is no lag in aileron response. But, VG's only slowed me down a few mph (I stall 42-43mph Vso), no really noticeable change as far as takeoff and landing distance goes. With some big tires and a diet my 108 should be ready for anything I want to fly into or out of.

Lot's of good info in this thread. The Stinson is a real joy to fly and a comfortable and stout backcountry plane.

VG's aren't supposed to be confused with STOL kits...... as mountainmatt stated, they improve control at low speeds. The slight benefit is a somewhat lower stall speed on most applications. They do work great on a Stinson, and are well worth the money.
The O-470 is a great engine for the Stinson..done a few. Right now, I'm doing one that gets the Lycoming IO-360 and an MT prop.. that one's going to be interesting to see.
The very best STOL mod to the Stinson is Crosswind's kit, that never has been pushed all the way through approval by the FAA. The performance is incredible! If someone has time and wanted to, they could maybe talk Charlie Center into working with them on final approval.
Overall, I think the Stinson is the biggest "sleeper" out there... excellent performance and reliability with a still small price tag.......
JH

The VG's will also improve STOL performance to one degree or another, because (as advertised) they add energized air into the boundary layer which keeps the flow attached to the wing at slightly higher AOA than otherwise possible. The slots will also do this same job (as mentioned), but on a Stinson the slots are only on half of the wing. So you should still see a noticeable benefit by installing the VG's, even if the half-span slots are already there. Even if the VG's don't do anything the slots don't already do (arguable), the VG's will be on the whole span which the slots aren't. Although I do not have any personal experience with Stinsons, I would expect there to be some measurable reduction in stall speed and max Alpha with the VG's.

Although definitely NOT do-able on a certified airplane without a bunch of testing and an official approval... adding the VG's likely would allow you to remove half or 3/4 of the twist (washout) on the Stinson wing... because the VG's are now there to get rid of that softened aileron control and tip-stalling problem which the twist was intended to solve originally. Having the wing flat instead of twisted would give you better STOL performance, at the cost of the airplane being less idiot-proof at low speed. Also, you would theoretically have to reduce your maneuvering and gust speeds because the twist lessens the loads on the wing during gusts and hard maneuvering.