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Experimental Cubs & Extreme Stol Devices, Flaps,slats,sl

My flaps are 94" long with 4" added in the cord with 55 degrees and .020 no problem.
 
Lowrider, the flap ribs on my Bearhawk are .025 2024 T3 and they go to 50 degrees. I think .032 would be overkill for your LSA.

Dave
 
Yes Sir...you guys are right on rib thickness for flaps. I had a long talk with my IA guardian angel today and he's with you....020 is fine for the flap ribs too. I have a tendency to over build so please let me know if I go astray.
 
Hans, Yes i think the slat will work with any practical airfoil. It is attached to what
looks like cub aileron hangers that bolt to the spar. A helio has a wing that is not
that different from ribblet or tailorcraft. Even most of the big jets. It just keeps the
air laminaled to the wing at lower speeds. The spoilers work well with the slot or
slat because you don't have to change attitude to desend. The angle of attack is
where you get the slow speed. My self I am going to link the spoilers with my
ailerons. They are small because of the big flaps. They will deploy only at the very
last of the stroke on aileron movment. Only when you need the boost, slow speed
in the wind. Wayne

Wayne, do you know if anyone has tried your slats with a Riblett wing, and if so how they worked compared to the USA35B?
 
Since we are back on this thread, the combo that is working really good is the Mackey slats, Keller double slotted flaps, and VG's. The VG's installed behind the slats and on the bottom of the stabilizer. I had a better gain with VG's on the tail than with CubCrafters gap seals.
 
This is a great discussion. FWIW, I am still trying to successfully persuade the local university to allow some test time on their wind tunnel, but I am having a hard time to get a student to bite on the idea to test some mods I have been working on... I´d like to see slats like the one on the Highlander on a USB 35B, 35B-Modified (piper) and the Riblett... I hear many great things on the Riblett, but still no hard data...

BTW here is an interesting thread hat I found that could add some color (or Colour depending on your english :)) to the discussion (link)
I don't see where Mackey is getting the stall speeds they advertise or, at least, talk about, except by dropping out of the sky (his landing technique).
Are Slats really better than Vortex Generators?

Pls, don´t shoot the messenger :peeper
 
Low rider: There is an excellent article in the new Kitplanes mag on the LSA Patrol FWIW.

Couldn't find it in the current on-line mag but did read about the Belite Ultralight...kinda neat idea.

I'm building a modified Riblet wing and I threw out the idea of the slats because it didn't look to me like they would be worth the weight (and potential cruise speed) to loose a few MPH on stall speed. I still don't know whether VG's would be worthwhile but I'm open to the idea once I get the bird in the air. Using a 0-320 and flaps should get me a little better take-off performance and the landing distance (yet to be determined) should not be affected to any great degree...I think.
 
BTW here is an interesting thread hat I found that could add some color (or Colour depending on your english :)) to the discussion (link)


Pls, don´t shoot the messenger :peeper


I would venture to say the dude on CC forum (RanRan) that made that statement has never flow with slats. The slatted wing will deliver as advertised. Also another point, at max gross weight the slatted wing is still extremely maneuverable at very slow airspeeds. If you remember way back when Penny Nixon did some various flight testing with the Dakota Cub slotted wing, Micro VGs, and BL VGs; he said the slotted wing out performed the VG equipped wings. A slatted wing is like a slotted wing on steroids. As I said perviously I like the VGs installed behind the slats for the very best performance.
 
Randy, I would like to know what is the slowest ground speeds you are seeing on your GPS with the Keller double slotted flaps with your SQ2 with no wind, at different altitudes and weight configurations, if you don't mind sharing that with all of us!
 
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Randy, I brought this up for the purpose of discussion and was not my own statement. My only experience (flying) in the VG vs Slatted is on the CH 705, I was privileged to fly this airplane backwards, that is it was build with a full size airfoil no VG to go a little faster from point A-B, Then, VGs where added and it made a tremendous difference on STOL performance at a minimal cost of cruising speed. Then one day a Slatted 705 showed up, and we had some fun with it! I can tell you, having tested the boundaries of the VGs on the one plane, then getting on the slatted, the approach was darn terrifying the first couple of times, by the time I solo the airplane that day, I can tell you that the Slatted wing was just amazing, it was nearly impossible to stall the airplane as the prop provided enough air s to hang that thing on the air!!!! Then there was a small burst of air on one of the demonstrations form the owner on a slow and ultra low flyby (sudden tail wind) and it fell on it's tail, it was so slow that the damage to empenage ruder and horizontal was very minor, it stopped fying only for a week or so jut to have a look inside and replace the bent metal. So as you can see, I am sold on the idea of the Slatted wing from a fun factor, but you do loose cruising speed and like everyting in life nothing is free :D.

Can you share your data on what sort of performance you are seen on the slats and double flap combination? What is you AoA at that perf?

Thinking out-loud, why not put a jack screw and change the angle of incidence of the entire wing on slatted airplanes? This was you can change the AoA of the wing while maintaining visibility :p haha!!
 
Thinking out-loud, why not put a jack screw and change the angle of incidence of the entire wing on slatted airplanes? This was you can change the AoA of the wing while maintaining visibility :p haha!!

something like this that can change the incidence of the slatted wing for landing and takeoff is truly the next "..rabbit pulled out of the hat..". for short-field performance.

The slatted a/c will seemingly hang on the prop as long as the power setting keeps it there. As power is reduced, the slatted aircraft descends comfortably in the high AOA attitude.

Those who have not flown a (Mackey) slat, and those who have not found the edges of it's envelope seem to disbelieve pilots who have experienced it.

It is very fun to fly!
 
Thanks Dave, I am for it and sure it would work great on my scratch built 205 HP cub. I just have to find a way either build a set or go back to work to buy Wayne's.
 
I must agree the slat does a fantastic job on the low_end! VGs are NO comparison!
Question.. the tail (on our build) has stopped flying if power goes away when behind the power curve.. this drops the nose a LOT.
not real desirable if no room to dive and recover. Do others remain in a 'parachute mode' if power goes away?
The CG is running 12" with pilot and light fuel, it of course helps to place 20# at the jack screw, just haven't flown other slatted machines.
 
mountainflier...............below 20. Will not reveil exact incase I decide to fly this SQ2 at Valdez next year. Ask your bud Billings, he's flown them.

SpainCub............Great conversation visited again. Previous response was not geared at "the messenger". Just my input on the subject.
Wheel landings in mid to upper 20's at moderate weights. Much slower as AOA increases. I'm addicted to performance and use all that's available today. Mix in some wind and game on, it's nothing to hover or put her in reverse!!!!!

Little Cub...........As said before nothing is free. There is a little lose of cruise speed for a huge gain on the bottom end unless it's the retractable slats. It does take power to maintain extreme AOA. With larger tail feathers and a larger range of trim of the stabilizer the nose can be held up better at idle power. On a larger scale to parallel this, if Boeing did not use leading edge devices, VGs, and multiple stage fowler flaps to slow down all the airports would have to greatly lengthen the runways. Just saying since Boeing uses all the goodies too.

Clifford...........I have no plans for you, but I do know who can sale you slats ready to go.


Those who have not flown a (Mackey) slat, and those who have not found the edges of it's envelope seem to disbelieve pilots who have experienced it.

It is very fun to fly!

Dave.......... well said!!!!
 
Clifford- to my knowledge there are two sources..

1- Wayne Mackey (aluminum slat)
(406) 232-1370

2- Randy Apling (Carbon Fiber about 9#)
Plaschem
Randy Apling <carbonconceptsak@gmail.com>
(907) 376-7505

hope that helps-

frank
 
....something like this that can change the incidence of the slatted wing for landing and takeoff is truly the next "..rabbit pulled out of the hat..". for short-field performance.
...

I got it worked out in my head, quite simple... if anyone wants description to try to make it.... could even make it a bolt on affair to test with(no wing mod?) on a real cub etc....
 
I must agree the slat does a fantastic job on the low_end! VGs are NO comparison!
Question.. the tail (on our build) has stopped flying if power goes away when behind the power curve.. this drops the nose a LOT.
not real desirable if no room to dive and recover. Do others remain in a 'parachute mode' if power goes away?

The Helio uses a long high aspect ratio stabilator for it's tail. This gives it the power for low speed. Perhaps if you built a high aspect ratio (longer) stabilizer and elevator for your Cub you would not loose the control? It's certainly worth a shot.
 
Frank, all the Mackey slatted airplanes that I have flown will lower the nose if power is reduced.

A large surface area and undercambered stabilizer airfoil section would certainly make some difference and assist keeping the nose up with less propwash available to boost "regular" surfaces. I believe the "double-ender" is using this scheme.

On the other hand, lowering the nose as power is reduced seems like a good thing. ...and.........something needs to counteract the pitching moment of our airfoil and flaps and slat-boosted flow...........nothing is free or we'd all be using helo's.
 
Perhaps if you built a high aspect ratio (longer) stabilizer and elevator for your Cub you would not loose the control?

Frank, all the Mackey slatted airplanes that I have flown will lower the nose if power is reduced.

A large surface area and undercambered stabilizer airfoil section would certainly make some difference and assist keeping the nose up with less propwash available to boost "regular" surfaces. I believe the "double-ender" is using this scheme.

Thanks for the comments.. been considering more duct tape mods, should be pretty simple to try a flying tail and more area. Like Dave sez it's always that trade off but the weight added is a good thing back there if we can gain low end stability. Will give it a try.
 
I got it worked out in my head, quite simple... if anyone wants description to try to make it.... could even make it a bolt on affair to test with(no wing mod?) on a real cub etc....

Can we fold 'em at the same time please ;-)
Would love to hear your thoughts Mike..
 
I have flown 2 SQ2s that had Kellers stabilizer, 3" over size elevators (cord & span), and the longer jackscrew that did a nice job holding the nose up. But as with any airplane that I have flown, it takes power to reach the critical AOA.
 
Back when I was still thinking about using 750 slats I added 2" in cord to the elevators and rudder to get more authority at slow speeds. I have most of the parts for the Riblett wing but have not started working on it yet...Summer has too many distractions. I'm still fascinated with the slat idea, originally spawned by the Storch wing on a Cub idea. One of my big concerns with slats is that it seems to need power to keep the nose up at slow speeds, so what happens when you loose an engine and need to dead stick in somewhere? Do you run into the nose drop issue that Little Cub mentioned or can you overcome that tendency with additional airspeed by just pushing the nose over without power and land at a slightly higher ground speed?
 
As was said before, it takes power to hold that nose up. In fact, part of the thrust is "lifting" a certain amount of the aircraft's weight.

When that power is removed the nose will come down. If dead stick.....the nose will lower and you will fly it like a normal Cub.

Those nose high landings are not an "every time" operation.

The beauty of the slats, which is usually overlooked by the uninitiated, is the very sweet and solid and FUN handling when very slow. The Mackey slatted birds will do a 180 degree in barely a wingspan if slowed to very high AOA before initiating the maneuver.

The slatted airplanes act like every other Cub when the nose is kept at 'normal' angles of attack.
 
PS. When "little Cub" was talking about the "...tail has stopped flying..." he is talking about loss of the down force provided by his "up" elevator.......

.....in other words.........when the down force is lost......the nose drops.

...so you see......a slatted airplane acts just like an unslatted airplane when the power is not there to help provide elevator authority to hold the nose up.

I have yet to fly one of these with a CG far enough aft to maintain a "parachute mode" when the power is reduced. It might be a fearful prospect. D
 
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