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DW
11-17-2009, 06:23 PM
Does anyone have photos of the droop aileron system pulley layout, cabin controls, and the workings in general?

Cubus Maximus
11-17-2009, 09:42 PM
http://www.supercub.org/photopost/data//512/medium/DSC00222.JPG

http://www.supercub.org/photopost/data//512/medium/DSC00223.JPG

http://www.supercub.org/photopost/data//512/medium/DSC00224.JPG

http://www.supercub.org/photopost/data//512/medium/Drooped_Aileron.jpg

When the camera shows this L-21 from directly above you can see the aileron droop system pulleys:

http://www.alaskaaerials.com/video/super-cub-anwr/

Steve Pierce
11-18-2009, 07:35 AM
Dennis you need to pay Jerry Burr a visit.

Iflylower
11-18-2009, 10:57 AM
I think DW would be interested in Helicopters as long as they had big tires!

:D :D :D :D :D

tw172
11-18-2009, 09:23 PM
I am building an experimental/Pacer. Where can I get the technical details of the drooped aileron system?

gander
11-18-2009, 10:17 PM
D&E has a drawing of a droop system using the pacer style set up. From what i remember it is a whole lot simpler than the cub style. If i were doing a droop system on a cub i would use the 12 style controls and reroute cables, you could build your own bell cranks and add a additional arm on them to operate spoilers for positive control at low speeds something that is missed on all cub modified systems i have seen so far except for the highly modified 12 that calkins and erikson did. It all sounds heavy to me.

bob turner
11-18-2009, 11:03 PM
How is the low speed roll control on this bird?

Robertson had to reduce the droop for roll control. At full droop, low speed control was barely adequate on the 180/185.

Dave Calkins
11-19-2009, 12:03 PM
How is the low speed roll control on this bird?

Robertson had to reduce the droop for roll control. At full droop, low speed control was barely adequate on the 180/185.

Bob, if you are asking about what Gander called "...highly modified 12 that calkins and erikson did..." , the roll authority with the coupled roll spoilers is excellent. The roll spoilers will become a standard on a good-flying drooped Cub, in my opinion. Others without roll-spoiler have scared a few pilots, as they need a full boot of rudder when down and dirty to affect a course change...so I am told.

Gander mentions "...it all sounds heavy...". An aileron droop system is not heavy. A roll-spoiler system is not heavy.

DW
11-19-2009, 12:22 PM
Dave can you tell me what a roll spoiler is and does anyone have a pic of one?

thanks
DW

cubflier
11-19-2009, 12:27 PM
Gander mentions "...it all sounds heavy...". An aileron droop system is not heavy. A roll-spoiler system is not heavy.

How much did that highly modified 12 weight? It would be nice to see it perform some day.

Jerry

Dave Calkins
11-19-2009, 12:53 PM
Dennis and Cubflier, Hello.

Yes, I can tell you what it is, and yes, I have a picture of one.
The "Custom Cruiser" is heavy. It is a Smith PA-12 replica with 5, count 'em, 5 doors, aux tanks, full metal headliner and interior, 4-Atlee long steps, etc............................................... .................................................. ...etc............................................ .................................................. ......etc..................... performance-wise, you would be blown away that a heavy "Cub" would fly like this. It proves that the aerodynamic mods on it are working. This aircraft will turn around on its wingtip when slowed-up.

First, the picture, showing an inboard and an outboard spoiler. The outboard spoiler is coupled proportionally to the ailerons only when the aileron-droop has been selected. Also, the inboard and outboard spoilers are both deployed simultaneously and symmetrically on both wings as a descent spoiler system, which is aLOT of fun.:

http://www.supercub.org/photopost/data//500/medium/IMG_1856.JPG

This roll spoiler system mimics the Helio Courier "lift interrupter" system in shape of the blade. The blade is about 29 inches in span and deploys about 3 inches above the wing upper surface.

It is molded carbon fiber to save substantial weight over the aluminum/steel Helio-style blade-assembly. It deploys through a slot in the upper wing surface about 6 inches aft of the front spar and is situated to take advantage of "spoiling" a portion of the high-speed air coming through the Wayne Mackey slats.

The spoiler both creates drag and interrupts lift on that portion of the wing, assisting in bank and controlling adverse yaw (adverse yaw is why we have rudders, to help keep a turn coordinated).

The roll spoiler provides very good roll authority with an aileron droop system and a Wayne Mackey slat system, with everything hanging out and the a/c at minimum controllable airspeed.


Another factor on this modified Smith PA-12 replica is that the PA-12 aileron belcrank geometry was significantly changed to provide greater differential ('up' aileron goes up more than the 'down' aileron goes down) in order that with full aileron droop selected, and the control stick racked all the way over, the 'down' aileron doesn't go any further down, but the 'up' aileron actually does go up.

This differs from some recent iterations of the droop aileron system.

mvivion
11-19-2009, 01:30 PM
For years I've wondered why someone hasn't installed spoilers on a Cub. Interesting description, Dave, thanks.

MTV

behindpropellers
11-19-2009, 01:41 PM
For years I've wondered why someone hasn't installed spoilers on a Cub. Interesting description, Dave, thanks.

MTV

Tim Allen's 2+2 has spoilers. I think it was built 20 years ago.

gander
11-19-2009, 01:46 PM
perhaps a more efficient approach may be larger flaps like 12 plus feet and shorter ailerons but use spoilers maybe even deeper frise style ailerons like on a helio, they would require counter balancing. It would be easier to build vs the drooping ailerons plus spoilers and results would probably be the same. I still think the more you put on the heavier it gets and is the pay back in performance worth it????? But it sure is cooool.

cubdriver2
11-19-2009, 01:47 PM
Taylorcraft L2 also 60 + years ago

Glenn

cubflier
11-19-2009, 03:08 PM
The ideal droop system for me would be on that has an on/off capability and is light. I don't think I would need a ton of droop either. Maybe a couple of inches or so max.

Has anyone ever weighed a specific droop system? Not much sounds great but I'm just wondering what they really add.

Jerry

DW
11-19-2009, 03:30 PM
Wayne said his weighed about 3 to 4 Lbs and you can pull it on or off as needed.

skywagon8a
11-19-2009, 04:41 PM
What ever drooping system that you use, you should not have it mechanically tied to the flaps. It becomes a problem in a crosswind when you need all of the up aileron that you can get. The spoilers as seen above, or something like them, should solve this problem. The flap/aileron link is the problem with the Robertson.

gander
11-19-2009, 06:47 PM
Droop systems with out spoilers are a compromise, if you add spoilers to a droops system or large flaps and small ailerons with spoilers you can have your cake and eat it too.

bob turner
11-19-2009, 07:29 PM
So the answer is that, without spoilers, drooped ailerons are not a good idea. That is what I was thinking.

I love the idea of spoilers and Fowler flaps, and Mackey leading edges. That sounds like a winner!

I fly an L2 Taylorcraft with spoilers, and they convert it to a moderately fast Piper Cub - when you get established in the flare, you pull the spoilers and land. Not legal, but sure beats sailing down the runway in full flare mode. They are truly neat!

skywagon8a
11-20-2009, 06:56 AM
So the answer is that, without spoilers, drooped ailerons are not a good idea. That is what I was thinking.

This is not an accurate answer. I have had drooped ailerons on my 185 for many years and would not want to be without them. I just don't use them in strong crosswinds or when landing. Without them, I would not be able to get out of the water, on amphibs, while indicating only 37 knots. They need to be able to be operated independently of the flaps.

palhal
11-20-2009, 10:48 AM
I have drooped ailerons on my SC and I have made them to droop 1/2 of the flaps just like the German Storch. I can select flaps only with out the droop also.

With ailerons drooped 1/2 of flaps still allows me to weave around the trees on short finale.

You have to learn to fly the aircraft with the droopys. If you don't have an aileron disconnect you approach with a little flap and as you get closer you apply more and on very very short finale you pull all of it.
You have to be ready to use rudder on the flare to control roll.

Also if you fly the airplane on short finale and cut the power to glide in like most pilots do, the droopys don't control roll very good.

If you make your approach by hanging it on the prop, the droopys work a lot better for roll control.-----Take care

Dave Calkins
11-20-2009, 11:35 AM
perhaps a more efficient approach may be larger flaps like 12 plus feet and shorter ailerons It would be easier to build vs the drooping ailerons plus spoilers and results would probably be the same. I still think the more you put on the heavier it gets and is the pay back in performance worth it????? But it sure is cooool.

Long flaps/no droop..............Perhaps. I believe we will have an answer this spring. (Wayne Mackey never sleeps).

I believe you are "...leaving some performance on the table..." when you don't camber the entire wing trailing edge (TE). We have discovered that roll spoilers allow us to have authority and also camber the whole TE.

Long flaps/no droops easier to build? maybe.

More you put on.................adds weight, no argument! Some things are worth it, some aren't. I don't see a need for 5 cabin doors and a baggage compartment you can drive a jeep on.......................BUT my Cub will have slats and selectable droops (though I never turn off the droops since the roll spoilers work so well on the Custom Cruiser).....after my C180 flies and my Bartender floats.

One beauty of the droops is the deck angle with them is 5 to 10 degrees less.....in other words.....Fly along with the flaps out and slowed waaaayyyy down, then droop the ailerons, and the nose will come down, yet the a/c doesn't gain speed..it only gains over the nose visibility..........................worth pure gold!

I believe Tim's 2+2 is set up with descent spoilers.

Dave Calkins
11-20-2009, 11:50 AM
The ideal droop system for me would be on that has an on/off capability and is light. I don't think I would need a ton of droop either. Maybe a couple of inches or so max.

Has anyone ever weighed a specific droop system? Not much sounds great but I'm just wondering what they really add.

Jerry

I no longer turn the droops off................up to a gusty 18MPH 45degree crosswind. I have not tested it beyond that with a crosswind landing or takeoff.

D

Ak
11-20-2009, 10:04 PM
Does any body no if the top cub kit will work with atlees under seat battery tray?

RMEAV8R
11-21-2009, 11:46 AM
Anyone have drooping ailerons, slats and vg combination? I read on another post that vg's and drooping ailerons work pretty good on 12's , anyone have an 18 with that combo?

Dave Calkins
11-21-2009, 12:01 PM
Anyone have drooping ailerons, slats and vg combination? I read on another post that vg's and drooping ailerons work pretty good on 12's , anyone have an 18 with that combo?

Wayne Mackey has been recommending VG's one inch behind the slat. Probably a lot more -18 based aircraft than stuff like Ron Kakeldy's Custom Cruiser ehich utilizes the slat/vg/droop configuration.

PS The wing incidence on the custom cruiser has been increased. It is NOT a PA-12, nor an -18 either.

gander
11-21-2009, 12:02 PM
Dave, i still believe just having large flaps with short ailerons with the spoilers inter-tied to then is probably the way to go. When you start putting handles in the cockpit all over to control ailerons and another for spoilers it gets more complex and heavy and there is not that much room in a standard 18 style fuselage. This is coming from a everyday flyer, hunting, spotting alaska usable working plane approach. The less gadgets to deal with the better.

aktango58
11-21-2009, 12:14 PM
The pitch angle entices me!

For a certified plane, how much does it cost to do this mod, (while in rebuild), and how much total weight?

Thanks

George

DW
11-21-2009, 04:19 PM
George
Which mod configuration are you looking for? There's been several discussed here.

Dennis

Dave Calkins
11-21-2009, 09:21 PM
For a certified plane,,,,,,,,,,,,,,
Thanks

George

haahahahahahahahhahahhahah :lol: What does it cost to get an STC? multiply that and testing costs x3 and add the cost of an aircraft with the mods. .....uh, um, uh, you do the math.


Gander, of course simplicity is best. "....The less gadgets to deal with the better...." But if nobody played with this stuff, it'd keep us in the 35 HP J-3 era. You wanna be in the 35HP J-3 era, the Helio era, or what? Guys have tried very short span ailerons on Cubs with long flaps.......ain't good. I'm sure there is a balance somewhere, but doing a Helio-looking Cub wing has been tried and failed. Works for the Helio, but not the Cub. I personally think Jerry Burr is onto something with his short flaps (stock flaps in the propwash), and long, drooped ailerons.

There is something coming down the pike that oughtta be very cool. I can't let it out of the bag. John, I believe you know. We will see.

gander
11-21-2009, 10:08 PM
I would disagree with you dave. I sure wont have too many bells and whistles on my plane, but that is what is great about exp planes. I think there is also much to be gained in airfoil choice and modification. It seems most are just using prepurchased ribs which limits them, perhaps if a better airfoil was used there would not have the need for such complex mods. It would nice to see more people make there own ribs and play with where the center of lift on the wing is vs the fuselage i bet these foils that some say are inferior would excell in max gross performance. most foils that people say didnt work you must look at how it was matched to the fuselage and whos ribs they were using is a limiting factor, we need more fabricating and less assembling.

aktango58
11-21-2009, 10:28 PM
For a certified plane,,,,,,,,,,,,,,
Thanks

George

haahahahahahahahhahahhahah :lol: What does it cost to get an STC? multiply that and testing costs x3 and add the cost of an aircraft with the mods. .....uh, um, uh, you do the math.


Gander, of course simplicity is best. "....The less gadgets to deal with the better...." But if nobody played with this stuff, it'd keep us in the 35 HP J-3 era. You wanna be in the 35HP J-3 era, the Helio era, or what? Guys have tried very short span ailerons on Cubs with long flaps.......ain't good. I'm sure there is a balance somewhere, but doing a Helio-looking Cub wing has been tried and failed. Works for the Helio, but not the Cub. I personally think Jerry Burr is onto something with his short flaps (stock flaps in the propwash), and long, drooped ailerons.

There is something coming down the pike that oughtta be very cool. I can't let it out of the bag. John, I believe you know. We will see.

Is there an STC for the droop aileron???

I thought there was. That mod was the one I was wondering.

gander
11-21-2009, 10:30 PM
Cubcrafters use to sell one but i believe they no longer doo.

Dave Calkins
11-22-2009, 01:07 PM
I would disagree with you dave.

Disagree on which point?

Also, I said earlier that Long flap/very short span aileron has been tried and failed. I must say that I don't recall that a roll-spoiler was incorporated, nor do I know what airfoil section was used.

Also, a very good flap system may void my whole argument...........but as soon as you have a 'better mousetrap' (better flap), wouldn't it make sense to use it on the whole trailing edge (droop ailerons) and gain high lift/slow speed performance over the whole wing?

About gadgets......again, we could all be flying souped up 35 HP J-3's. "...WOW, you got a 65HORSE in that thing? Must be like a rocket!!"

Dave Calkins
11-22-2009, 01:13 PM
My whole reason to care about stuff like this is to have a VERY slow flyer.

You could look at Valdez last year and make some assumptions that we've found the limit on Cub slowflight. Greg-Mauleguy in his stock round tipped winged-experimental "Bridge"(...uncovered tail) VS MikeO's RedneckCub with lots of bells and whistles and they were pretty close........

........there are several elements that each has left "on the table", that were not incorporated and that promise better slow flight performance.

.....We haven't seen the slowest flying Cub-type aircraft yet!

gander
11-22-2009, 01:18 PM
Your right Dave, lots of unknowns and not everybody has the same purpose with a plane. Some want the Valdez contest style and some want a working plane that is more simple. Both are great and as we all know we are splittin hairs on these mods because a stock lite weight cub will go most any where a modified machine will go.

DW
11-22-2009, 01:32 PM
Thanks everyone for your input it's great to have this forum to discuss all the options, pros , cons, :agrue: and then be able to build a wing for your mission with some confidence that it will work for your application, I have made a decision on what I will build, but of course it will probably change, but for now I'm off and running thanks again everyone.

DW

Dave Calkins
11-22-2009, 01:54 PM
because a stock lite weight cub will go most any where a modified machine will go. If you assume that, then you will discover that you are mistaken. And I haven't mentioned how the new ideas will positively affect float-performance, not just Valdez-style. Working, Standard-category airplanes? Please, let's not argue the application to that. The application is valid even if not yet STC'ed, and there are lots of 'certified' Cubs running around 'technically unairworthy', and/or just 'ratty' if you want to argue that. If you want simple, simply limit yourself to it.

DAVE

PS, until a couple years ago, I thought I had flown, owned and been around enough Cubs and Cub-Drivers to have a pretty good idea of what a Cub can do.

Around the same time I got the chance to fly the WORST flying stock -18 I've ever flown, and also to fly and develop a highly-modified airplane that exhibits the best in-flight maneuvering and slow-flight ability I have experienced, with plenty of avenues to develop more performance left in the design.

These are the reasons I maintain my position.