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Thread: Leading Edge Cuff

  1. #41
    nanook's Avatar
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    cuff

    Nome? Who's in Nome? Diggler are you hearing voices again?

  2. #42

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    delete

  3. #43
    Steve Pierce's Avatar
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    Thanks Jerry. I think I now understand what the airflow is doing. Reminds me of a 1950 Bonanza I annualed just before the new speed restricting AD came out. The guy I did the work for sold it and over a year later the new owner was hanger flying with some old timers with the speed restriction thing came up. The old timer thought it was ridiculous so they went up to prove it. They proved it all right. Twisted the tail around and tweaked the rt. wing. They were lucky and got it on the ground. The call was made because some how when the insurance company came to call the log books disappeared and he wanted me to tell them I annualed it after the date that I did. Nah

    Other side of the coin though, I have learned many things from the old timers over the years. I guess you have to use personal judgement and consider the qualifications of the person talking. I for one trust Jerry's advise and it appears he has the test flying data to back up everything he has taken the time to post on this site.

    Everybody knows about opinions and that everyone has one and they are entitled to them. Don't understand why you have to poop on someone elses.
    Steve Pierce

    Everybody is ignorant, only on different subjects.
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    Thanks bda thanked for this post

  4. #44
    Gary Reeves's Avatar
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    I have had a running argument wih myself for several years about frost stalling you quicker. It all started with one of those 10,000 plus in the bush pilots telling me that it would. Well, if Howard said that it did, I believed that it did, but why.

    The only data that I could relate too was the equivalent sand grain roughnesss data on flat plates. The drag goes up and goes up fast as the roughness increases. The adverse pressure gradient does the same. This results in a tendency to stall sooner at the same angle of attack, and sooner at increased levels of roughness. I don't think any of us need to consider the too smooth parts of the data.

    Air just does not see the same wing that our eyes see and frost changes the aerodynamic characteristics faster than it changes the physical shape.

    So - I felt comfortable that once again conventional wisdom had a basis in fact and I could find a logical theory to support it.

    ADD THE CUFF

    Now would the frost effect be enhanced by addition of a cuff? The cuff provides pressure distribution peak more toward the leading edge and raises the overall negative pressure effect on the lifting surface. It also makes the fight against the adverse pressure gradient occur a bit further foward on the wing ( a good argument for having vgs when you add a cuff). If you add roughness to the suction surface the same things happen with or without a cuff. You stall sooner at the same aoa. The question is then- does the cuff with frost stall sooner than a nonmodified wing with frost. I suspect that under some conditions it could, since the aerocharacterists are those of a wing at higher aoa anyway.

    BUT, I don't feel comfortable with the theory. I dont have to worry since I have an unmodified leadinig edge, but if I did, I sure would spend more time making sure the frost was gone and really make sure the vgs under the tail were free of ice.

    GR

  5. #45
    cubdrvr's Avatar
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    Since I started flying everything I learned was DO NOT TAKE OFF WITH FROST. I have to believe that everyone else was taught the same thing.
    I would like to hear from the guys who, unintentionally or otherwise, have experience with takeoffs and frost.
    Before the days of wingcovers or the luxury of a hangar we did it all the time.......if it was really bad we'd run a rope across most of it. Maybe we were lucky, but I have never had frost on a cub make a real noticeable difference. Is frost that much thicker or heavier in AK?
    "Sometimes a Cigar is just a Cigar"

  6. #46
    Dave Calkins's Avatar
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    Frost can take many forms. It can be different from day to day in the same location. "Alaska frost"?? Maybe it's different up north. Nooky, you got an answer for that?

    I was taught, as we all were, to never try to fly a frost-covered airplane.

    Subsequently, I learned through another's experience, and then my own, that a moderately loaded Cub flies fine with a bit of smooth Frost.

    I would never take off without first wiping down the big hoary crystals. Those things usually just fall off with a bit of wind, but maybe I'm still supersticious about frost, so I smooth them first.

    I'd be intersted to hear from you aerodynamicists how much more critical a Cessna airfoil section and wing are to frost, rain, bugs, etc. than the Cub section. I have my ideas.

  7. #47
    Crash's Avatar
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    Cuff

    I like Nooky's point about addign this then adding that and in the end you have a big heavy pig that flys poorly, you have a ton of money in it and nobody will buy it bacause it's so screwed up. I have seen a few of these.

    I was taught to make sure the front 12" and back 12" are absolutly clean of frost, the middle you just knock down. The airfoil attaches in the first 12 inches and seperates in the last 12 inches first when you stall, so these areas must be clean. My old guide friend was talking about getting up morning after morning to fly out clients and gear with 3-4 Cubs. The stock winged Cubs they would just hit the front and back as I said above. On the cuffed winged Cub, for some reason, just would not get off well without the wing being really cleaned. There might have been other reasons. Having been around both types of wings I have not seen the difference, or should I say "not enough" to make me want to do it. Crash

  8. #48
    Cub Kid's Avatar
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    Quote Originally Posted by diggler
    aoiergalknv;ljhgnLSdh;alwigh;lsnvLKSdj';liejlk

    Whats the elevation of Nome and average temp?
    About 36 feet at city field, and 24.9 F yearround average if memory serves me correctly

    Bill

  9. #49
    nanook's Avatar
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    cuff

    When I said "idiotic test pilot BS" that was not directed at jerry. That statement meant, that anyone who choses to fly with contaminated wings is a test pilot. There are too many variables to deal with. I once watched a CE-206G loaded with triple packs (pop,mail) run off the end of the runway, first flight of the day, frost on the wings, the 206 would barely fly in ground effect and wouldn't climb past the end of the runway. You can do the same in a cub if you load it up enough. Who cares whether it has stock, cuffed, VG's, extended this or that. That CE-208B that just went in to Lake Erie w/10 souls on board landed in freezing drizzle loaded up and took off with crap on the wings and heavy, they made it less than a mile. In Dillingham a couple of years ago same thing with 10 souls, got high enough before he stalled to kill everyone on board. Same thing in Barrow 4yrs. ago took off with contaminated wings and a fuel imbalance, hit the ice covered ocean off the end of the runway and killed 8. Same scenario every time, in too much of a hurry to deice and killed everyone on board.

  10. #50
    Jerry Burr's Avatar
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    Ice, Frost, and Stuff.

    Hellow again. I'm happy to say that I can agree at least 50% on what Crashes friend says. The leading edge is vitally important in terms of ice and frost. The trailing edge on a -18 is a different matter. The trailing edge on a -18 goes turbulent at very low angles of attack. It is caused by a poor design on the wing trailing edge. False spar if you will. I posted a video a while back showing exactly what I am referring to. The -12 false spar was a great improvement in that area. Presence or absence of frost in that area I believe is minimal. As far as testing Cub or Cessna wings with frost, I think it would have to be done with artificial frost. Similar to the artificial rime ice that NASA used to test T tails. It would be the only way to get back to back tests. I tried a few stalls during my icing tests just to see if there was a way big difference, and the only thing that was readily apparent was that the ice quickly started building on the bottom of the leading edge. Which brought in a (transition) factor which would junk any serious test results. I also agree with Nanook in that a speed airfoil will always be exponently more affected by (stuff) on the wing than a lowspeed lightly loaded high lift airfoil. Aviaiton has enough pitfalls and there is always the (Murphy effect) waiting around the corner to trip you up. There is really no reason to take additional chances with the likes of ice or frost. ( No, I wasn't referring to you Murph).. Jerry.

  11. #51
    Gary Reeves's Avatar
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    Jerry Burr said

    The leading edge is vitally important in terms of ice and frost.

    Dave Calkins wondered about bugs.

    I have come back with so much bug goo ( I think the green stuff is aphids) on the leading edges and prop that it would make the frost seem smooth. I assume that this build up provides the same risks as frost.???

    I picked up a product called Rejex X or something like that at Fun n Sun last year and applied it to one wing. Fewer bugs stuck and they were easier to get off, but then last year was a low bug year at our place.

    Sooo, what about bugs Jerry?

    GR

    Cessna wings- I was under the impression that the 4 series NACA airfoils lkie the 2412 on 172s were designed about the Clark Y which is very tolerant to crap.

  12. #52
    Jerry Burr's Avatar
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    Leading Edge.

    Sorry Gary, I'll try to be more precise. The leading edge is vitally important as it is the only (Flying) portion of the wing as the stall is approached. The entire wing from the front spar rearward is completely stalled and the airplane is supported by the leading edge only. Which is why the forward mounted V.G.'s work so well at high AOA and or wing loading. Bugs / Ice / Frost can also work as V.G.'s. The problem is when the thickness or placement of the junk becomes more detrimental than beneficial. I have only studied the 35-B mod. and cannot speak to the other airfoils. Jerry.

  13. #53

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    Thanks everyone for the input. I am amazed by the diverse opinions everyone has on this subject and may others for that matter. I don't understand why the cuff is the best thing going for one person and the next guy says he would pay to take it off. I guess with everything else, people have different experience levels. I have noticed that approximately 75% of the people on this web site are what I would call traditionalist and think nearly any mod to the standard cub deters its performance. I am not a traditionalist, I like to experiment.

    While I am sort of venting, I have always wondered why people dislike the 180 HP conversion? For the life of me, I can't understand why anyone would want a 150 or 160HP cub when they could have a 180HP. obviously cost is a factor, but don't put the 180HP mod down just because you can't afford it. Sure, you say put high compression pistons in a 0-320 and you have a 180. Well, put high compression pistons in a 0-360 and you have a 200. The 0-360 is the lightest horsepower gain for the weight than anything going. I know some of you think the 0-360 burns more fuel than the 0-320, this is not totally true. My experience has shown that at the same airspeed the fuel burn is nearly equivalent. Others say the 0-360 vibrates too much, balance your prop. I have had all three versions and there is no comparison!

    Sorry for my outlash, I wish we/I would post our thoughts more objectively with actual data like Jerry Burr rather than everyone being so subjective

  14. #54
    Jerry Burr's Avatar
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    To weight or not to weight.

    I like Nooky's point about addign this then adding that and in the end you have a big heavy pig that flys poorly, you have a ton of money in it and nobody will buy it bacause it's so screwed up. I have seen a few of these.
    Crash.
    I have a question for you Crash. It concerns the Pig Effect. If you add a lift device to a wing that weighs 2lbs while sitting on the ground, I call that static weight. If in the air that same device adds 8 lbs of lift to the wing, it is lifting 6 more pounds than it weighs. It's a net gain of 6lbs dynamic lift. BUT because it is mounted on the WING it then becomes "Pig Effect" according to your theory.
    On the other hand if you add: A. Dodge folding seat. Airframes unbreakable lift struts. P.S. Engineering IC w/stereo w/ external input. HD gear + three inches. Rear seat storage container. Metal extended baggage with metal on the floor, sides, and roof. 29" tires. Pilot side door. (Your equipment list according to your posts) This is all static weight and adds only to gravity. Yet because it is added to the fuselage, and not the wings it doesn't become fair game for the Pig Effect.
    Please explain the basis for your Pig Theory. Thanks. Jerry.

  15. #55
    Bill Rusk's Avatar
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    As Jerry has pointed out the more critical the airfoil the more susceptible it is to contamination. This mostly applies to the laminar airfoils with very high Reynolds numbers. The soaring community and the glass slipper folks (Lancair, Glasair, etc) are very familiar with this concept. The air stays attached much further aft than on our low performance airfoils but has less energy and so will separate much sooner with a massive increase in drag. Correspondingly, when the airfoil is in the drag bucket it has much lower drag and so goes faster.
    When Burt Rutan was in the initial design phases of the Varieze he had a great, but very critical airfoil, on the canard. When the aircraft flew through rain it would descend because the rain contaminated the canard airfoil and caused a loss of lift. Ie it would not hold the nose up. By redesigning the airfoil, he got a little more drag and a little less lift in normal circumstances but it was no longer as susceptible to contamination.
    If the cuff makes the airfoil more critical (logic would seem to support that as nothing comes free in aerodynamics) then it would be more susceptible to contamination, HOWEVER, as Jerry Burr also pointed out, without wind tunnel testing in a controlled environment you really don't know and it is all speculation. Too bad John Roncz does not frequent this forum. (Quite possibly the premier airfoil designer alive today)
    If you are asking a lot from the airfoil, ie max gross, short strip then you are going to need all she can give and that requires a clean wing. If you are really light, such that you are not demanding max performance from the airfoil (surpluss of lift) then you might get away with some contamination. As the carny barker says "you pays your money and ya takes your chances, step right up"

    Bill

  16. #56

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    i think rutan found that by adding vgs to his canard he could make it fly in the rain, or keep producing lift, ask jerry on this one.

  17. #57
    Bill Rusk's Avatar
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    To All

    Confession time. Egg on the face and all that. Dave Calkins caught me on my last post. I should have said "low reynolds numbers" rather than high. In a nutshell the closer to the LE that the boundary layer goes turbulent the lower the Rn # all other things being equal. Rn = Vx/v where V = velocity(Airspeed) x = distance back from LE and v = kinematic viscosity.
    Since the low performance airfoil boundary layer goes turbulent much closer to the LE than a slick laminar flow airfoil that gives us a smaller value for x and hence a "LOWER" RN.

    Boy do I feel like an idiot. Thanks Dave for setting me straight.

    tempdoug
    Putting Vg's on would re-energize the boundary layer and might keep it attached longer which would probably have worked. Note what Jerry Burr was saying about the Vg's attached close to his LE cuff and reattaching the airflow there.

    Bill

  18. #58
    Cub Kid's Avatar
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    Re: To weight or not to weight.

    Quote Originally Posted by Jerry Burr
    I have a question for you Crash. It concerns the Pig Effect. If you add a lift device to a wing that weighs 2lbs while sitting on the ground, I call that static weight. If in the air that same device adds 8 lbs of lift to the wing, it is lifting 6 more pounds than it weighs. It's a net gain of 6lbs dynamic lift. BUT because it is mounted on the WING it then becomes "Pig Effect" according to your theory.
    On the other hand if you add: A. Dodge folding seat. Airframes unbreakable lift struts. P.S. Engineering IC w/stereo w/ external input. HD gear + three inches. Rear seat storage container. Metal extended baggage with metal on the floor, sides, and roof. 29" tires. Pilot side door. (Your equipment list according to your posts) This is all static weight and adds only to gravity. Yet because it is added to the fuselage, and not the wings it doesn't become fair game for the Pig Effect.
    Please explain the basis for your Pig Theory. Thanks. Jerry.
    Jerry,

    You didn't mention one of the most important ways to help lighten your airplane...Lighten up the pilot. With doctor approval, I highly recommend diet and running, as many pilots can afford to lose more than enough weight to offset almost any mods they put on. I personally enjoy distance running at around 5 am, as there isn't much traffic (i don't like breathing exhaust, as that is kinda counterproductive). It also has the side benefits of added health, and coupled with a weight training program helps improve asthetics, which the women seem to like.

    Bill
    Likes bda liked this post

  19. #59
    Cub Kid's Avatar
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    HMMMM I think my last post might be a little off topic.

  20. #60
    cubdrvr's Avatar
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    Re: To weight or not to weight.

    I personally enjoy distance running at around 5 am
    You have my utmost respect Bill.... :P ...unless there is something to shoot or catch I don't know what 5 am is............
    "Sometimes a Cigar is just a Cigar"

  21. #61

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    Naah, it was directly on topic. Shedding 50 pounds would be one of the cheapest mods I could do, albeit one of the most difficult to 'install'. Thanks for reminding me.

    " Putting Vg's on would re-energize the boundary layer and might keep it attached longer which would probably have worked. Note what Jerry Burr was saying about the Vg's attached close to his LE cuff and reattaching the airflow there"

    They wll also trip the flow to turbulent if it is not already so. The advantage being that the trip is often to turbulent attached flow, rather than turbulent seperated flow. Generally, I'd rather have an early trip from laminar to turbulent attached flow than a later trip from laminar to turbulent seperated flow.
    JimC

    JimC

  22. #62
    Jerry Burr's Avatar
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    Weight

    Hi Kid Cub. I couldn't agree with you more!! One year I lost 17 lbs to compete at Gulkana. I couldn't take any more off the airplane so I was next in line. At my last physical the Dr. told me to gain 3 or 4 lbs. Don't hear that too often. I run 30 to 45 miles per week. Keep up the running. Jerry.

  23. #63

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    Just wanted to add my .02 worth. I let Charly Center talk me in to putting leading edge cuffs on my 18 after I put it on its back following one of my "wish I would have looked over that landing area better" landings on a Montague Island beach.
    This was 17 years and 2000 hours ago. I never could notice a difference other than it made it more difficult to put the wing covers on, due to the stall fences which are part of the mod. Maybe if you really fly your cub on the edge all the time you would notice a difference, but the way I fly I couldn't discern any.
    As far as frost, I try to use covers and not fly with frost on the wings. The few times I have I couldn't tell much difference from the wing I had before the mod
    Bottom line-- I wouldn't Put this mod on unless someone was holding a gun to my head!!

  24. #64
    nanook's Avatar
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    cuff

    I'm with you on that point Rock. Most of the cub drivers in the North are using their cubs to get themselves and friends out to hunting and fishing spots. Many are trapping or spending weekends out at the cabin or camping/ skiing. In other words we aren't parking in the hangar every night like our more civilized brethren to the south. The got to have every lift or power mod. crowd don't have to deal with some of the practicality issues that we do in the North. Lightweight cubs are the way to go. I could care less about Gulkana and how many mods that you can put on your cub to get off the ground faster/shorter, some people seem to be obsessed with that whole scene. I don't like the way a cub flies with extended wings. In the forward CG range(180hp) the tail becomes less than effective at slow airspeeds. I'd rather land at minimum airspeed without having to carry a bunch of power.
    > ksecub says we would all have 180hp. cubs if we could only afford them. Man are you clueless or what. I've yet to fly or see a lightweight 180hp.cub. It's an oxymoron. ksecub when you get that 1300lb(after you empty it) pig stuck in the snow by yourself out in the middle of nowhere, you might begin to understand what I'm talking about.

  25. #65
    Crash's Avatar
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    Jerry Reply

    Jerry: This is a reply to your previous post, or should I say attack called "Pig Theory". Lets get one thing straight. I fly a late 70's Piper PA-18 Super Cub. You fly a modified 1930's J-3. They are apples and oranges as far as comparison. The "Gold Standard" I use to base my comments on is the factory 150 hp Piper PA-18 not your "one off", super modified J-3. This site is called "SuperCub.org" not "Modified J-3.org". Back to your comments:

    1) The Atlee Dodge folding front seat adds ZERO weight.

    2) I use Northland Mfg. 1/4" birch plywood floor boards, the same thickness and weight as Piper, only better quality and better looking.

    3) I use .016 2024 T3 for my interior panels, Piper used .020 S.O. with a heavy tar based product sprayed on the back side for sound proofness. They are twice as heavy as mine.

    4) I remove the vacuum system and all the heavy instruments, filter, regulator, hoses etc. that go with it.

    5) I replace the starter, alternator, and oil cooler with all the light stuff.

    6) I gut all the wiring and use basic electrical and breaker swithes in the panel.

    7) All of the above removes about 45 lbs from the original PA-18.

    8) Then I believe in adding some extra horse power to get the crate quickly moving so the wing will produce the required lift in the shortest distance possible.

    9) I don't use my plane to impress the ladies with how short I can get off. I haul moose, gear and people in mine. When was the last time you hauled a moose plus 300 lbs of gear, 450 miles home in one trip?

    I respect your knowledge on short take off, special use wings and if I needed a set I'd come to you. We use our planes for different purposes and live in different environments so we will never see eye to eye. I will leave it at that. Best wishes to you always. Crash

    P.S. My post was just agreeing with Nooky from Nome, why didn't you get on his case, after all he was the one stirring up the big VG debate.

  26. #66

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    Wow Nanook I feel the love! This is a great country, everyone can express their opinions freely and everyone can disagree.

    Nanook, I know you are a Husky lover so you might appreciate my new wing project. I am putting Husky flaps on my PA-18 wings. However I am extending the wing and adding droopy ailerons. I know, I am ruining another perfectly good set of Cub wings. I am a disgrace to Super Cubs.

    Nanook, I think a stock cub is great, its just fun to experiment. I get tried of watching sitcoms at night. I need to do something to entertain myself.

  27. #67
    Jerry Burr's Avatar
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    Pig Theory.

    Hi Crash. You want to get it straight. I want to get it right. My Cub is a 1947 J-3, and at one time it had a stock 150hp S.C. wing on it.
    The (Pig) theory was from your post. And it was not intended to be an attack but a question. Which I still don't believe was answered. A couple of questions. How heavy is your Moose that you are hauling with 300lbs of gear? And what is your empty weight? Thanks Jerry.

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    Crash's Avatar
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    Moose

    Moose weight: I wieghed one with about a 60" rack and it came in at 580 lbs. The rack is around 50lbs. Crash

  30. #70
    Jerry Burr's Avatar
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    History

    Hi Nanook. Thanks for all of the interesting information about you Alaska Bush Pilots. Maybe you have forgotten that I was flying for Fish and Game on the chain in a Super Cub when I first heard about Gulkana. And yes the Super Cub had a Cuff and long wings. Jerry.

  31. #71
    nanook's Avatar
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    cuff

    ksecub: Husky lover? I'm more partial to German hunting dogs, huskies are kinda dumb, they won't bring the bird back they just eat it. I hear you on the sitcoms, TV has gone down the tube.

    > Jerry: and your point is? (besides being old like me.)
    On the Chain? I'm sure you mean the AK. Pen. No one with a brain would fly a cub out the Chain.

  32. #72

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    Re: Moose

    Quote Originally Posted by Crash
    Moose weight: I wieghed one with about a 60" rack and it came in at 580 lbs. The rack is around 50lbs. Crash
    How do you lift a 580 pound anything into a supercub. Or is a "moose" a another local colloquialism term for a big woman and she actually climbs up into the plane herself?

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    delete?

  34. #74
    Crash's Avatar
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    Moose

    Diggler, you forgot the half rack of beer I took along to drink on my flight home.

    It was no GW kit, just a mile long F-15 (abandon airbase) runway. I know a guy that flys gas out to is lodge. Get this... 2 Dodge tanks = 61 gallons, an old Sorsen 80 gallon belly tank and 30 gallons in fivers on the back seat. That is about 1,100 lbs plus plane and pilot. Takes him the entire Birchwood runway to get off.

    Last fall I hauled two Caribou (300#), my 160lb son, our entire camp and gear plus about 40 gallons of gas out of Iliamna in the PA-14. It got off in about 400' with a 10mph wind coming down the runway. These Cubs will haul a load if you let them. Crash

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    Has anyone done any testing before and after install of the cuff to see what if any increase in AOA is achieved or if the power on stall speed is reduced. Perhaps Jerry can comment on this.

    I am guilty as most of us in making multiple mods at once during rebuild and not being able to distinguish which mod generates the most effect. In a perfect world we would all make one mod at a time and evaluate the results before adding another, but this is not always practical.

    I am getting ready to redo my experimental wings and I can't make up my mind on which leading edge device to put on if any. So far my choices are Wayne's slats, cuff, or nothing. I will put VGs on what ever I do. I have Waynes droopy ailerons and will be putting extended (110") Husky slotted flaps on the wing. The ailerons will be full length out to the squared tip. I also have Sullivan's tips. I welcome your comments and suggestions.

  36. #76
    kase's Avatar
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    I was in Sioux Falls last weekend and flew a 160 hp PA18 with Dakota Cub Slots on a Square wing.. Flaps are 90 1/4 in and standard length aileron moved out to the tip. Took off and landed in 150 ft grass area with 375 lbs of people and 36 gal gas, 10 kts wind. I would pull full flaps before I thought it would fly and every time it popped off the ground and with the slot you can climb as steep as you want. Its the 3rd aircraft I have flown with the slot and every time they really impress me. I think Waynes slat would be the way to go for you ksecub.

  37. #77

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    Kase,

    Thanks for the reply. With the slotted wing, did you feel like you had to fly at a higher angle of attack in order to fly slower? Everything I read about slots and slats indicate that the coefficient of lift does not increase until the angle of attack increases beyond that of the stall of the plain or flapped wing. This to me means that the takeoff distance will not be shortened unless you have some means of increasing you AOA by longer gear or other means. I have 3" extended gear and 31" BW with the zero thrust line mod and don't really want to reduce my over the nose visibility any more. As far as landing goes, I guess you can tip the nose way up and fly slower, but I question how short I will really be able to land over an obstacle like a river for example when touching down on a gravel bar. I had a Husky once and I think I could get it to land shorter than a cub if I really tipped the nose up and did not care were I touched down. I could always land a cub shorter when coming over an obstacle because I had visibility and I could hit my spot better with confidence.

    I really want to put the slat on but this visibility issue really concerns me. I have thought about adding incidence to the airplane by changing the wing attach points on the spar. I can increase the incidence by a degree or so this way which should help a little. According to the books I have been reading, the sharp increase in lift is a result of delaying the stall by increasing the AOA by approximately 10-15 degrees. Do you think a person could get used to flying at these large deck angles and still be able to hit your spot accurately.

    As I said before I really want to put the slat on, if nothing else to experiment. It looks like a blast to fly. I would be interested to hear what people thing about it in a real bush environment, not just as a show plane.

  38. #78

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    i think the fact that you get to fly slower means you land shorter and can get stopped much sooner. so its safer and even if you misjudge the spot some you still are stopped shorter. maybe. i think getting used to flying nose high is what it takes as you still can look to the side. taking off is another issue as you say as its harder to get the high angle for best efficiency. with the helio you arent totally flying nose high with the slats.
    i like the idea of slots on a wing for slow flight, and am considering building up a set for something super cub like.

  39. #79
    kase's Avatar
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    ksecub,
    I dont know if I can really answer your question. You do need a higher AOA for the slot to work. This cub was on standard gear with 26 in tires. I was just coming in and doing a normal short field landing like I would in my cub. I felt like the longer flaps were making it take off and land short more so than the slot, because of the standard gear . I would like to fly that cub some more and then put on 3 in gear with 31 tires and try it.

    I flew Dakota Cubs Pacer with the slotted wing and it has really tall gear. It comes off the ground way before you think it should, and thats with a 150 Lyc. It flys exactly like a super cub.

  40. #80
    StewartB
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    ksecub,
    I looked pretty hard at Storch kits for awhile. Slats, high AOI, spectacular (reported) STOL performance, but really slow in cruise. Maybe the Storch specs can help you decide.
    SB

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