TopCub

Hi Any of you guys have Jim Richmonds stol kit? I have his BLR vortex generators and believe they add a bit of safety to my cub at low airspeeds,but would like to know more about the drooping ailerons from someone who has them. When I had the cub rebuilt I installed the vortex gen. had flew it for many hours without and after a couple hundred with I would not go back.

CC PA-18-180

Heard the FAA was going to give Jim Rischomd (Cub Crafters) a type certificate for the 180hp PA-18 so he could make an end run around Piper. Hmmm... Read CC lititure on their "Top Cub" drooping ailerons mod on their web site. They say "this kit is not for everyone". I have never flown them but have talked to two different high time Alaska guides that flew them on two different planes and both said they were down right dangerous in a cross wind. Crash

stol

Thanks for the input crash,stands to reason.

Crash,

Just to clarify, you are talking about the drooping alierons not the VG's, is that correct?

Thanks.

sj

Yes I am asking just about the top cub stol kit. I have had the Blr vortex generators and strakes on my cub since new rebuild and think they are worth it to me.

SJ, I think he is talking about the drooping ailerons. I have heard the same comments from others.

Steve

Would anyone land in a strong crosswind with full flaps? No! Knowing that how should a reasonable pilot came to the idea to lower the ailerons in such conditions?

For idiots flying is dangerous, but idiots we are not. Hopefully !

Hans

Strong Cross Winds

Swiss Bush Pilot: I would hold off calling high time Alaska bush pilots idiots until you come fly with us in 30MPH + (thats 41 kilometers to you) crosswinds and land with, ... FULL FLAPS. Yes Steve I ment drooping ailerons. Crash

drooping ailerons

I don't have experience with cubs with drooping ailerons but do have experience with Cessnas with Robertson's stol drooping stuff. Really resricts roll control making it interesting in gusty crosswind conditions. I'm not the greatest stick but I seldom or never used full flaps in the Cessnas in gusty conditions.

About 30 Mph crosswinds and cubs. I can't park mine in a 30 + crosswind and keep it rightside up unless tied down. I almost always use flaps landing a cub, regardless of the wind. Problem I've had is not in the landing but keeping the cub landed. Bad feeling having the upwind wing suddenly start flying when you thought you landed 5 seconds before. I'm thinking of modifying my flap system and when dumping the flaps having 40 degrees up flap to hold her down and keep her from skipping out in the brush.

The Alaska guys are good. From experience, they land in lets say interesting places. The winds up there can be brutal, but they have alot of money and bending airplanes is not a big deal. Right!! Unlike the Alaska guys, I've found winds too strong for me and my plane and found other places to land.

:lol: Don

Yeah, just for fun, let's say that ALL Alaskan Cub pilots are "good".

Kidding aside, yes, full flap X-wind landings.

Back to the CC aileron droop system:

It's always on, and if you select flaps, you've drooped the ailerons, every time. This is not good for a turbulent air day.

Jerry Burr has a set-up that he can incrementally adjust to provide 0 to full aileron droop with flap actuation. It's a simple system that weighs 5.6 pounds. And the beauty is that non of the changes are in the wings, except for the removal of the aileron horn-stop mounted on the center aileron hinge bracket.

Check out this system, and you'll not even consider the CC.

Sure, the CC and Robertson droop systems work for higher lift at slower speeds, there's no question. But they lack flexibility due to their "always on" or "full-time" operation. And as for the Robertson on the Cessnas, They add weight, take a bunch of time and parts to install, must be rigged VERY accurately and maintained carefully...And have you considered, oh Robertson-equipped Cessna driver, that on flap-motor-equipped Cessnas, the left flap AND the aileron are being driven by ONE thin cable that is required to be tensioned FAR!!! above the stock Cessna spec., and the flap motor is now driving the whole trailing edge. Lots of guys LOVE their Roberston system, other guys think it's not worth the compromise.

Back to personal opinion, just like always.

Dave Calkins.

Very interesting to hear that not the same aerodynamic laws shall apply on the other side of the Atlantic. As lowered ailerons as I know them can only be moved a fraction the way they would be able in the up position, I guess it is quiet obvious that the aircraft cannot compensate for the same amount of crosswind in the down configuration. In Addison the plane will sit down at a slower speed and therefore the influence of the crosswind factor will be increased. As every pilot must know this, one can not say that such a STOL kits are to dangerous in crosswind conditions. Dangerous can only be not to take this in account.
That?s what I wanted to explain in my first statement. Maybe my English is not good enough that this was clearly stated and understood.
And of course I do not predict that Crash will crash ahead of me in the tiny steep uphill glacier spots I am used to land on here in the Alps just because I do not like his statement about my skills either.

a all in all friendly Hans

Since Americans were the first to accomplish powered flight as the world knows it, we also hold the right to make the aerodynamic laws.

That sounds quite pompous, though it's a joke, and not ALL Americans are the jerks that foreigners think they are. Why don't foreigners think ALL French are jerks???

If a pilot doesn't desire to touch down slowly, crosswind or not, that's his choice. But he'll still have to deal with slowing down through the landing roll-out.

I claim the right to choose slow or slower touch-down speed, by using full flaps, even in a X-wind. And then dump them off upon touch-down.

If I had an ON/OFF droop aileron system, I'd choose to turn it off for x-wind and/or turbulent air operations. Good roll authority is more important in those situations. That's another good reason for VG's. There's no question that they enhance slow-speed aileron authority greatly from that of the un-VG'ed wing.

The point I want to make is that the droop aileron system will decrease roll authority, and that's a problem on a turbulent day. And that's a problem with an x-wind.

Landing slow, with flaps, in an x-wind is NOT a problem.

Dave Calkins.

Swiss Cub, what altitudes do you generally operate at, on glacier?
What's that orange Cub weigh?
Fernandez ski's?
Do you ever go on straight skis? What type/manufacturer?
Ever dink a Cub? Or would that put you out of the rental pool? Or are you one of the lucky few with means to own a Cub in Europe AND be able to pay for fuel?

Thanks in advance for your answers, It's nice to get input from a different perspective.

And, your english is fine, just consider carefully how you word your statements, as we Americans should be careful with our statements.

Yes, we have glaciers in Alaska, too. Some big, some SMALL. Yes, some of us ARE idiots, but from what I know, Crash is NOT one of them.

Dave.

Hans

Sorry Hans; I didn't mean you couldn't fly and I amended my previous post. I just don't like to called an idiot for landing in crosswinds with full flaps. A 20,000 + hour guide that dosn't have an auto, but flys his PA-18-150 when he needs to go somewhere (lives in the Bush) handed this tecnique down.

Even though my handle is Crash, I have only wrecked one plane (six snowmobiles and three cars, but they don't count) and it was not knowing how to handle a crosswind when I first started. The nose low, full flap, drive it on hard and drop the flaps works for our winds here in Alaska. The Swiss Alps might have a different type of crosswind that the "float it in" method might work better on. You do have socialized medicine there, no? Crash

Crash

I am fine. I not ment that landing full flaps is idiotic in any case. Think it can work to a certain extent. I myself would rather not lower the ailerons in extreme wind conditions due to restricted control over the longitudinal axis in heavy gusts. Unfortunately the systems I know have flap setting and ailerons lowering combined. In that respect one has to be very careful. I personally think that the limitations of a STOL kit like that is not worth the benefit.

Hans

I was wondering how much the drooping ailerons helped in a landing, It seems most all mods have a trade off. Also the Dakota
cub has a leading edge slat. (or is it slot I get them mixed up) Has any one had any experience with either one? The Sherpa has a fowler flap and it seems to me that it would produce the most performance for the money.
Although I have been flying since 73 I have only been interested in super cubs that past year. This web site has been the best learning tool I have found on the web. Thanks in advance.
Ed

Wish Jerry Burr would chime in here.

I'm guessing he would say something like...."increasing the camber of an airfoil will increase it's low-speed lifting capability, as long as the aileron in this case isn't drooped more than 30 degrees...". And it's a tradeoff worthwhile for the ultimate STOL operations.

Jerry also has something to do with the Dakota Coyote, of which there are pictures in the gallery section of this website. This "Dakota Coyote" has a leading edge slAt.

Dave Calkins.

Droop Ailerons.

Hi. So far, Dave is bang on. And there is little more for me to add. I've been flying with the droops for 16 years now and wouldn't get rif of them for anything. I will answer some questions that I am always asked as I know they will come up. If you are going to have droops, it is best to have them tied into the flap system in some way, and to be able to adjust the droop from all to none when the flaps are deployed. A lever for the ailerons has been tried and is not cool. The droop ailerons cause an adverse nose down pitching moment when applied by them selves. Just as the flaps cause the nose to pitch up. If you have two levers, it is just not workable. When the aileron droop and flaps are applied together the pitching moment is cancelled. 0 to full flaps with no trim required. My response to the full flap debate in a cross wind is that it depends entirely on my weight. If I am very heavy, I can use full flaps, and no droop. If I am very light which is most of the time, I use 1/2 flaps (which allows a good speed reduction and also good control) drive it on and when the flaps are then dumped it will leave me below flying speed instead of at flying speed . (Where I would be without any flaps). If the Swiss Cub tends to be on the heavy side , full flaps probably work fine for him. I enjoy Mr. Potts writings. Just remember he is dealing with a stock wing. Any time that I am landing into a decent wind ( 80% of the time) I use full flaps and 15 deg. of droop. I am slow enough that the tires don't even squeak if on pavement. (At that time the {up} aileron is level with the rest of the wing). At 26deg.of droop the aileron never comes close to being level with the wing. (used only in emergency or competetion). In that situation, the roll control is minimal and directional control has to be watched closely. But that condition is only used 4-5% of the time. In my opinion the benefits far outweigh the 5lbs of weight. Yes I also use the same flap aileron condition (full and 15 )for every takeoff. For manuvering over your favorite rack, 15 deg of flaps and 10deg of ailerons will just park you there and you don't have to circle. ( most ailerons are rigged at 3/8" droop. It gives good control and little loss in speed. Rig them 1/2" high and you gain speed but loose control authority. BUT if you lower them 1/2" aka droop. You gain condiderable aileron control at a minimal loss of speed that you don't care about anyway.) The droop makes the ailerons a lot better for a long time before it starts to make them worse. I agree with Dave. The Top Cub kit has a serious problem. The last time I was at Dan's in Anchorage, he had 3 or 4 kits laying in the corner of the shop, that had been removed. Like any other Mod. If you don't NEED it don't even consider it. It can get you into trouble if used improperly. Just like your Cub. Jerry.

Fowler.

Hi Eddie. I thought It would be better to address the Fowler in a different post. They are a great flap on a wing designed for them. I know of three Cubs with the C-182 type fowler. The first was the Thompson Cubby in Anchorage, then Gary in St. Maries Idaho, then John in Hood River Oregon. The latter two were built as heavy haulers. They have (lots) of extra power and do what they were built to do. They can operate out of an average S.Cub strip safely. And carry monsterous weight. The Cub wing with it's wimpy rear spar was just not designed to carry the strain of this type of flap. Byron Root worked on this problem for years. And he built some very wild Cubs. He pretty much decided he was not going to get there from the Cub wing. That's why the Sherpa. It was a total new design built around a gigantic Fowler assembly. I'm not saying it can't be done on a Cub, but it is not praticable for the average Cub builder. If you read the bad press given to a 4 inch extension to the inboard end of an existing flap. Imagine what a fowler does. Jerry.

David, I don't know as much about aerodynamics, aeronautics, or cubs as Jerry does (I'm much impressed with Jerry's expertise), but I thought I'd pitch in on this subject. You can use the principle of superposition to predict the performance of drooped ailerons. After doing so, you will get a slight drop in efficiency due to the vortex spun off at the juncture between the flaps and ailerons, but that juncture and vortex is usually there anyway. Also, for those who may not be familiar with it, Mark Drela's XFOIL is superb at calculating the performance of airfoils. Earlier versions of XFOIL are available as freeware.

Has anyone considered the use of an airfoil similar to the Selig S1223 or S1223rtl for a high lift cub? It is a pretty draggy section, but the CLmax is truly remarkable, even when unflapped (about 2.1 to 2.2 without flaps).

Re the French, I made my first trip to France September before last to give a talk at Toulouse on automatic gust load alleviation in the azhdarchidae. I was much impressed with how friendly and considerate everyone in France was. I didn't meet a jerk the whole time I was there.

Like Jerry, I also think you're pretty much spot on.

All the best,
Jim Cunningham

There are some pictures of the Dakota Coyote with slatted wings elsewhere on this site, but whatever happened to the postings and information about the leading edge slats on this aircraft (posted by Jerry Burr and others)??

Hans

Slats.

Hans. Wayne Mackey built the slats on the Cubs in the photo album. Denny Martels Cub ( Dark Red and White with long gear ) and the Dakota Coyote Cubs. He plans to market it as a kit. Contact him at stolmaster@earthlink.com or 406-232-1370. He is just north of Miles City Montana. I can't wait untill someone has the money to put the slat on a Dakota Cub slotted wing. It should haul the freight. Jerry.

droop ailerons

This is for Jerry Burr, do you have a diffrent system for drooping the ailerons than the top cub kit? If so how can I find more out.

Droop.

Yes my system is different than the Top Cub kit. In my airplane it weighs 1/3 as much and is (on demand) . Most of the info is posted above. Wayne Mackey is using my system on the Dakota Coyote and others that he is building. It takes some changes to use it in the -18. I call it a closed loop system. It is not mechanical/cable like the Top Cub kit. Contact Wayne at the above post or me at flycubs@pioneernet.net Jerry. P.S. Mine is not STC'd. It has field approval.

top cub

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droops

i forgot to say never install droop ailerons w\out vg,s.this will greatly increase your lost aileron authority with drooping ailerons.it will not make them normal but will help.

Sleep

Hey. If you aren't interested, for gosh sakes don't read it. Try Strobes or Spin on oil filters. Keep looking untill you find YOUR thread. Jerry.

I've got to say this is interesting stuff.

There is a question that just begs to be asked, though.

With all the mods you guys are putting on your planes to make them fly so slow, land so short, and under such good control... WHY ARE YOU LANDING IN A CROSSWIND?? Why not just land ACROSS the runway?

You mention problems taxiing in strong winds. WHY NOT JUST "HOVER" TO YOUR PARKING SPOT? Then you don't have to taxi!

Just kidding.

There is some GREAT information on this site shared by knowledgeable folks who show that they really know how to make the Super Cub perform.

Reply.

Hi Longwinglover. You don't have to kid. Both of those are exactly what we do. The crosswind landings are a problem when there are trees on the downwind side of the runway. As far as parking, you just land on the spot and throw a shoe on the ground behind the tire to hold it untill you can jump out and tie it down. Many times I have recieved tower permission to land on the runway exit. If you land at 45 deg to the exit, you can handle a real bad 90 wind. I have also taxied downwind to a beautiful fuel truck to parking. I thanked God he was a pilot. X-country sometimes demands tougher choices. Jerry.