Another tailwheel discussion

[av8rps]

Welcome to the forum. This is a great resource, especially as you get further into your Kitfox ownership.

I think learning how to fly in a Kitfox, especially an early one, will make you a better pilot as they are a control sensitive and somewhat unstable compared to your average Piper or Cesna. After putting more than 2,000 hours on Kitfoxes and Avids, and flying a bunch of other general aviation aircraft over the years, I personally find the Kitfox a bit harder to fly than many other taildraggers, but it is not the raging monster some claim. However, some Kitfoxes and Avids have had really bad luck when using the Maule tailwheel (as in wrecked) which will make it nearly impossible for ANY pilot to fly, UNLESS it is set up correctly. (I know this from first hand experience - a master flight instructor that specializes in tailwheel put an Avid on its back because of a Maule tailwheel. And this guy knows how to handle tailwheel airplanes)

So if you have a Maule tailwheel on it we should talk before you get into your training in it. That could be the reason for 6 previous owners?

Paul


Hello all. I completed ground school this spring and want to get my SP ticket. I searched ALL summer for an affordable Kitfox to use as a trainer. The closest facility to me with a LSA for training is about 65 miles distant. I don't know when I decided I HAD to have a Kitfox but I did. I finally found a decent one about two weeks ago. It is currently in the warehouse where I work. I want to get to know this Beauty intimately before I get a waiver to use it for my SP training. I've been lurking on this and the Avid forum for some time. I have certainly gleaned a great deal of knowledge from those forums. Thank you all for an education and your thoughts. Lou

[KFfan]

Thanks av8rps!

I thinks part of the attraction to the KFII is the relative "instability" of it and the challenge of a tailwheel. I have read many posts, here and elsewhere, that mention if one can attain the tailwheel endorsement one can handle most any other.

Please don't think that I am overly confident. I just have a good handle on some of the things to expect and my own abilities when learning new skills in other aspects of my life.

Included with the plane is a new Matco wheel with a Carlisle 4ply 9X3.5-4 tire.
Oops! I'll have to watch where I land. It states "NOT FOR HIGHWAY SERVICE"! :D Any thoughts on this wheel? I have not yet mounted it.

I have ordered the history from the FAA. I should have it tomorrow. Hopefully it will be clean. I did search accident/incident files and was not able to find this ship there.

[cgruby]

Welcome to the forum. This is a great resource, especially as you get further into your Kitfox ownership.

I think learning how to fly in a Kitfox, especially an early one, will make you a better pilot as they are a control sensitive and somewhat unstable compared to your average Piper or Cesna. After putting more than 2,000 hours on Kitfoxes and Avids, and flying a bunch of other general aviation aircraft over the years, I personally find the Kitfox a bit harder to fly than many other taildraggers, but it is not the raging monster some claim. However, some Kitfoxes and Avids have had really bad luck when using the Maule tailwheel (as in wrecked) which will make it nearly impossible for ANY pilot to fly, UNLESS it is set up correctly. (I know this from first hand experience - a master flight instructor that specializes in tailwheel put an Avid on its back because of a Maule tailwheel. And this guy knows how to handle tailwheel airplanes)

So if you have a Maule tailwheel on it we should talk before you get into your training in it. That could be the reason for 6 previous owners?

Paul

Hi Paul

I caught your comment about Maul tail wheels. How about elaborating a little as to what are some of the pit falls regarding this tail wheel and a Kit Fox. I've got one on my Type III, but haven't found any reason why I would remove it. I've als flown several other airplanes with that tail wheel and other that a lot of slack in them, they work as good as a small Scott.

You really got my curious up.

[Av8r3400]

The main issue with Maul wheels is their propensity to prematurely unlock, going full swivel, if not set up perfectly.

In an early Kitfox (1-4), if the tail unlocks when you aren't expecting it, the plane will come around (ground loop). That is a guarantee. Especially with an inexperienced pilot. These planes are short coupled and quick on the controls.

It is highly recommended that until you gain a good level of experience, you remove the unlocking cam plate off the wheel keeping it locked to the steering chains.

I kept the cam off until I had 100 hours in my plane. By then I felt I had enough experience to handle it. Last summer I still looped my plane (luckily at a slow speed with no damage!) when the wheel unlocked unexpectedly.

[kmach]

I have a Matco 8" dual arm tailwheel , the lightweight one.

It has worked flawlessly for over 300 hrs.

It is much better than the solid 6" that was originally on it!

[TahoeTim]

Is the tailwheel on the S7 an issue?

[cgruby]

The main issue with Maul wheels is their propensity to prematurely unlock, going full swivel, if not set up perfectly.

In an early Kitfox (1-4), if the tail unlocks when you aren't expecting it, the plane will come around (ground loop). That is a guarantee. Especially with an inexperienced pilot. These planes are short coupled and quick on the controls.

It is highly recommended that until you gain a good level of experience, you remove the unlocking cam plate off the wheel keeping it locked to the steering chains.

I kept the cam off until I had 100 hours in my plane. By then I felt I had enough experience to handle it. Last summer I still looped my plane (luckily at a slow speed with no damage!) when the wheel unlocked unexpectedly.

I see your point. I've been slowly becoming acquainted with my Type III with a Maul TW. I have to admit, I've made some really spectacular landings, some bordering on almost an what some might consider an aerobatic maneuver. Allowing the airplane to yaw unchecked, will most certainly result in a GL, however, when everything else fails, there's always brakes. I have never considered removing the cam, I guess I like the full swivel capability too much.

Part of TW training is learning to deal with the monster. When I was a 16 year old kid, flying a Cub, I made a lot of crazy landings, but all my 60 years of flying, I've never ground looped one yet. I can't even phantom an experienced instructor putting an airplane over on it's back due to a tail wheel becoming unlocked.

Cheers,

[av8rps]

What Larry is saying here describes the problem well. The only thing I disagree with is that with experience you can learn to overcome the problem. You can't. You cannot train enough to be able to handle this problem.

I have flown airplanes with that tailwheel when it unlocked in flight (unknown to me at the time). And I will tell you even with a COUPLE THOUSAND HOURS in this type of an airplane, and mentally being on top of my game because it was a test flight, I was very lucky to get the plane back on the ground in one piece. Remove the swivel option by taking that cam out of the tailwheel as Larry described so well, and those same airplanes became extremely easy (by comparison) to fly.

So what's so wrong with Maule tailwheels? I'm not really sure, and maybe nothing if set up correctly (although I do have to admit that Maule aircraft are known quite well by insurance companies for ground loops....hmmm?)

Anyhow, on the Kitfox it is relatively easy to see if they are set up properly. Just put a sawhorse under the tail of the airplane until it is level and the tailwheel is hanging with no weight on it. Then while having one person by the tail, have another person go in the cabin and push the rudder pedals back and forth full deflection, while the person at the tail checks to see if the tailwheel unlocks (or will swivel freely). The tailwheel should NEVER unlock without weight on it...

It should only unlock when there is weight on it and inertia is applied one way or another to make it unlock. In other words, only on the ground. (aside from wanting it to swivel to push backwards into a hangar, or to turn 180 degrees really sharp into a parking space, why else would you want a tailwheel to fully swivel?)

Typically when I've found them to unlock without weight on them they unlock left more than than they do right. I'm not sure why that is, but it's not good either way when you are coming in for a landing and unknown to the pilot the tailwheel is now deflected 90 degrees from the direction the airplane is going. You can bet as soon as that tail hits the ground that you are going to go hard left (or right) just as if you had the rudder pedal to the floor and a brake locked. And because the Kitfox is a relatively short airplane, you will find yourself going off the runway at a 90 degree angle to the direction you were traveling just a second ago. If you're really lucky and very proficient, you might be able to fly away across the width of the runway (with lots of power). But much more likely, you will find yourself in one hell of a ground loop, typically burying the outboard wing into the ground while twisting and tearing at the rest of the airplane, which many times results in everything, the wings, the struts, the tail, and the fuselage being bent and twisted from the violent forces associated with such a quick direction change.

I'll fly a Maule tailwheel, but only with the swivel feature disabled. And if it isn't disabled then I will do a thorough check to see if it can be unlocked without weight on it.

Unfortunately because many Kitfox owners have never had a problem with their Maule tailwheel (they're blessed in my opinion), they can't understand how so many guys can groundloop their airplanes? And for those that have, they probably are questioning their own abilities as a tailwheel pilot, when it is probably more likely there was something wrong with their airplane.


The main issue with Maul wheels is their propensity to prematurely unlock, going full swivel, if not set up perfectly.

In an early Kitfox (1-4), if the tail unlocks when you aren't expecting it, the plane will come around (ground loop). That is a guarantee. Especially with an inexperienced pilot. These planes are short coupled and quick on the controls.

It is highly recommended that until you gain a good level of experience, you remove the unlocking cam plate off the wheel keeping it locked to the steering chains.

I kept the cam off until I had 100 hours in my plane. By then I felt I had enough experience to handle it. Last summer I still looped my plane (luckily at a slow speed with no damage!) when the wheel unlocked unexpectedly.

[KFfan]

I'm glad the subject surfaced.

"av8rps"
Thanks for a detailed, complete and graphical explanation. Yet another example of the insightful information freely given on this Forum!

Any known shortcomings for the Matco gear, anyone?

[Greensuiter86]

I too have the mauled set up on my model II. The previous owner put 600 hers on it with no issue, but I have a matco on my RANS and liked it so I bought another one (thanks Jay S!) But haven't installed it yet. Sounds like I probably need to. I'm also interested in any issues with the Matco setup? I'm not aware of any so far.

Jay P
N627C
KF II/ 582

[Av8r3400]

Another factor with the early planes is the rudder/brake peddles. As you push the left rudder peddle the brake on the right side comes toward the pilot making it possible to be pressing the right brake without wanting to. This works the opposite way also.

I've had this happen as well. The only solution is to recognize this right away, center the rudder and apply both brakes to stop the aircraft. Yes, very scary. Especially when you're looking at the trees on a narrow grass strip.

[Av8r3400]

I took this discussion out of KFfan's intro thread to stand on its own...

[KFfan]

WOW
I am going to look at that phenomenon tomorrow when I make my daily check. Have to make sure she didn't kick the covers off overnight....

[Greensuiter86]

So Larry, any particular negative experience with the Matco? I have a couple hundred hours on my old one with no issues but not on a Kitfox which is an entirely different bird all together.

Thanks

[av8rps]

(Moderator: I didn't mean to hijack this thread for our new member, so maybe if possbile the posts about the tailwheel issues could be peeled off and put under a new title labeled; Groundloops & Maule Tailwheels?)

Hey Chuck,

I can't help myself from commenting about your post here as it is such a good example of the point I was trying to make. Sorry about making it a novel, but I felt this was worth a good explanation. So here goes;

I learned how to fly in a J3 Cub in my teens. I didn't learn how to fly a tricycle gear until I was in my mid 20's. So it is safe to say I grew up on a tailwheel.

Consequently, it was a real blow to my ego the day I am test flying a friends' show quality Avid Flyer (that flew perfect) when I am beginning to think after 4 botched landing attempts that I am going to roll his beautiful labor of love into a ball. No matter what I did, I couldn't land it without losing control of it (full opposite rudder and brake were useless as it was all happening too fast to do that, and had gone too far left to try and turn it 90 degrees to the right before going off the runway). But finally, after countless go-arounds.... I managed to get it on the ground in one piece. The builder was there, so we looked at everything, tire pressure, how tight the bungees are, toe in and toe out of the main gear, etc, etc. And after regaining my composure, with slightly different air pressure in the tires and another wrap on the bungees, I tried it again, only to find out it was still impossible to land :eek::eek:. Again, after a bunch of almost ground loops that I managed to fly away from, I got it back on the ground. Now completely frustrated (and scared) I told my friend (who was not a pilot at that point) that I was afraid if I kept flying his plane that I was going to wreck it. Most confusing was that I had already flown more than 40 hours off this plane on floats, and all we were doing was trying it out on wheels so a local tailwheel flight instructor could start teaching him how to fly in his own airplane. So I knew this particular Avid well. Just not on wheels. And honestly, I had hundreds of hours in my own Avid as a tailwheel plane, as well as on wheel penetration skis, and never did I have an issue being able to land it. Also, fwiw - Just 3 weeks earlier I had completed 28 hours of instruction in an S2 Pitts biplane and was complimented for my ability to handle the airplane.

So I was feeling pretty beat up having this little Avid Flyer kicking my butt. As a last ditch effort to figure out what was wrong with his plane, the builder suggested that there was a cam on the tailwheel that if removed would stop the tailwheel from swiveling, which he thought might help the situation? Admitting that I knew nothing about his Maule tailwheel, I very reluctantly agreed to try it just one more time (:eek::eek::eek:). And the only thing I can say about that experience is that it was absolutely amazing to see what one little screw holding a small aluminum cam plate on a tailwheel could do for an airplane. That little Avid Flyer went from a raging monster to a really nice handling, predictable tailwheel airplane that handled like it should. It was much nicer than the Cub I trained in, or the Citabria my other friend let me fly occassionally. I could hardly believe it could be that simple.

The rest of that story goes like this; Now that the Avid was handling properly (but we didn't know what was wrong with the tailwheel so I told the owner to never put that cam back in unless he wanted some real excitement), I proceeded to teach his flight instructor how to fly the Avid so he could in turn train the builder how to fly in his own airplane. That instructor and I had a blast flying the Avid together for about 4 hours. He had never flown an Avid before, but after putting that one through the wringer, the more he flew it the more impresssed he became. I can't tell you how many take offs and landings we did, but there were a lot of them. He was extremely complimentary of the ground handling of the Avid compared to the "sloppy feeling J5" (his comment) he was instructing in at the time for tailwheel endorsements. After he was done with my dual, he did a bunch more hours on his own to satisfy his insurance company and then started training the builder towards his license.

All was going extrememly well with the training until one day when the instructor asked the builder why the tailwheel wouldn't swivel? The owner explained to him our previous situation, but the instructor said he should put it back in as he was confident he could handle whatever it was doing. So the builder did.

It was later that afternoon while they were practicing landings, the student lost control of the airplane just as the tailwheel touched, and they found themselves going across the runway sideways, 90 degrees :eek:. The instructor said he hit WOT (again no time for full opposite rudder and brake) as there was no saving it so he attempted to fly away crossways on the runway to avoid what he knew otherwise would have been a monstrous groundloop :(. The Avid having a high power to weight ratio did fly, but not soon enough. It was mid winter and there were high snow banks on the edges of the runway, and even though the Avid was beginning to fly out of trouble, the main gear wheels hit the top of the snowbank, flipping the plane completely on its back. The Avid was so severely damaged it needed wing repairs, strut replacement, and a new fuselage.

I am pretty convinced that if the instructor didn't have a father that is known as a extremely thorough aircraft mechanic, that instructor today would still believe that he had just screwed up that day by not saving the situatiion from the student. And so would have I. Heck, the whole local aviation community was critical of the instructor for his "screw up". (reminder to self; never be so judgmental, especially of your friends)

But his father found the problem after the NTSB left by just leveling the fuselage and inspecting operation of that tailwheel. And sure enough, with that cam reinstalled it unlocked with no weight on it. He knew it should require inertia and weight while on the ground to unlock it. So the instructor, the builder, myself and the father checked and rechecked that tailwheel with the cam in and out until we were all convinced that it was the problem. Avid at that time was consulted, but denied others having the problem. So we talked with Maule only to learn that they want the pivot pin on the tailwheel to be level, not canted forward or back when the aircraft is level, and for the rudder not to have so much throw that the deflection impact on the tailwheel arm can "shock" the tailwheel mechanism, unlocking it.

Now personally, I don't think any tailwheel should unlock in flight, regardless of how you have it "set up". So I'm not overly fond of Maule tailwheels for that reason. But again, some work just fine on some of our Kitfox fleet. But I feel sorry for the guys that have either wrecked their Kitfoxes because of that, or think of themselves as failures because they just can't fly a tailwheel. I know that has been the case with many over the years, and this is truly sad knowing there was probably a high percentage of those planes just had a tailwheel problem.

I agree with the comment about liking a swivel tailwheel feature. And in fact, there shouldn't be any reason you can't have a tailwheel that will swivel only on the ground. But when it breaks loose in the air, and you don't know that happened, you're not likely to have a good day.

There's a reason some airplanes use a tailwheel that locks in a straight position. In a Pitts S1 if you land on a narrow runway and your tailwheel is at all crooked, because the airplane is so short coupled and lands fast you will be off the edge of the runway before you will even have time to react. So many install a locking tailwheel to avoid that issue.

The Highlander group has learned that they don't like Maule tailwheels either after experiencing problems like I desribed (A friend just sold his Highlander with a Maule tailwheel to a guy who is using a tailwheel instructor for his transition training. The instructor ignored my advice about the Maule, but after scaring the bejesus out of himself with the Maule, that Highlander is now sporting a nosewheel...what a shame when it was easily fixed while still keeping it a tailwheel airplane :o) . Now the Highlander group recommend a tailwheel that is fully lockable (Jim Pekola tundra tailwheel as I recall). Ironically, when its not locked it doesn't even use chains to connect to the rudder for steering. Rather it centers on a detent in the air, and on the ground you have to apply brakes to make it turn left or right. I've flown one and I liked it. Other people that have flown it say it is almost as easy as a trike, and I mostly agree. It will always be a taildragger, but it is a really easy one with that tailwheel.

So, a Kitfox should not be a difficult to fly taildragger. Yes it is short coupled and quick compared to some other aircraft. But it shouldn't be a handful. If it is, check your tailwheel over closely. Especially if it's a Maule. And try it with the cam removed to see if the plane handles better. If it doesn't, then either there is something else wrong with your Kitfox, or you may need more training. But never just think it is you without first verifying the tailwheel working properly.

Paul



I see your point. I've been slowly becoming acquainted with my Type III with a Maul TW. I have to admit, I've made some really spectacular landings, some bordering on almost an what some might consider an aerobatic maneuver. Allowing the airplane to yaw unchecked, will most certainly result in a GL, however, when everything else fails, there's always brakes. I have never considered removing the cam, I guess I like the full swivel capability too much.

Part of TW training is learning to deal with the monster. When I was a 16 year old kid, flying a Cub, I made a lot of crazy landings, but all my 60 years of flying, I've never ground looped one yet. I can't even phantom an experienced instructor putting an airplane over on it's back due to a tail wheel becoming unlocked.

Cheers,

[Av8r3400]

Paul - This was turning into a very good, very informative thread on the merits of tailwheels. I wanted to make it something that can be searched for, for future reference.

S'all good. :)

[metalman]

Very interesting thread, I've got a mate with a KF and he has the cam removed on his maule TW ,he gave me a real rev about mine and as I'd never heard anything about them I just figured he'd made a bad landing and got a scare. As it is I have never really like the maule wheel on mine and have a new matco double sided pneumatic for my aircraft, hopefully it works well

[N981MS]

Just to give a voice to those with Maule tailwheels that "behave".

I have had 2 and not had any problems. Just got lucky, I guess, since I did not know I needed to check them.

One on a Maule M7 235 (about 150 hours).

One on the KF for 700 plus hours now without any problem.

I bet I'll check mine at next annual.

[av8rps]

Just to give a voice to those with Maule tailwheels that "behave".

I have had 2 and not had any problems. Just got lucky, I guess, since I did not know I needed to check them.

One on a Maule M7 235 (about 150 hours).

One on the KF for 700 plus hours now without any problem.

I bet I'll check mine at next annual.

That's what makes this subject so difficult, as some people have had good experiences with it, and others didn't.

Unfortunately most that had trouble with the Maule probably didn't even know the tailwheel was the fault of their problem.

Worth mentioning, I have a Highlander that has a Maule tailwheel. A friend of mine that flies bush planes for a living was leary of flying that very Highlander from hard surface because it was so squirrely, yet he's flown taildraggers his entire life. When I bought the plane the first thing I did was to pull that cam off the Maule tailwheel. Flew it home just fine, then tested it by leveling the fuselage, and sure enough, with the cam in place it would unlock with no weight on it. I'm still flying it with the Maule, but will probably put a Matco on it before I sell it.

Paul

[jrevens]

I'm not a big fan of Maule 6" tailwheels, but they have been used successfully on many different aircraft types for decades. It was the failure of a Maule tailwheel that preceeded the death of Ken Brock , a friend & well known aircraft builder, pilot, & parts manufacturer out of California. I don't like them, for that & a couple of other reasons, but the locking mechanism doesn't have anything to do, directly, with weight on the tailwheel. It is similar to several other designs in that it "breaks" at a specific angle of rotation. If set up properly - proper ratio between full rudder deflection & deflection of the tailwheel, along with proper spring tension - it won't break without some sideways force (i.e. - application of brake) while deflecting the rudder fully. This causes the wheel to rotate a little further (against spring tension) to the point where it breaks into full-swivel. Doesn't matter if weight is on the tail or not, although weight will usually decrease spring tension due to the geometry of a tail spring & the control horns on the rudder. Aviation Products, Lange, & some others work similarly. Scott & Matco work a little differently. I may not be clearly understanding what you're explaining, Paul, but set-up does definitely make a difference. Additionally, all bets are off if your wheel assembly is worn out, just like many things mechanical.

[jrevens]

I forgot to mention that my buddy Stan (Sourdostan) has flown over 2000 hrs. in his mod. IV Speedster, literally all over the USA & Canada, with a 6" Maule tailwheel. I never heard him complain about it. I know he's flown & landed in wild crosswinds many times - the wind does blow around here occasionally. Just sayin' FWIW.

[metalman]

Just fitted the new matco today, to early to tell if it's very different to the maule ,but the big difference is the pneumatic tyre, very nice ,on pretty rough gravel you can't feel the the tailwheel touch down ( I usually wheel it on) at all , now I just have to get the brakes working better, they only just hold at 3500 rpm , and sometimes they won't hold to do a tight turn,,,,,,

http://i40.photobucket.com/albums/e242/mattyw1966/Skywolf%20pics/imagejpg2_zps0ea8528a.jpg (http://s40.photobucket.com/user/mattyw1966/media/Skywolf%20pics/imagejpg2_zps0ea8528a.jpg.html)

[Dave F]

I forgot to mention that my buddy Stan (Sourdostan) has flown over 2000 hrs. in his mod. IV Speedster, literally all over the USA & Canada, with a 6" Maule tailwheel. I never heard him complain about it. I know he's flown & landed in wild crosswinds many times - the wind does blow around here occasionally. Just sayin' FWIW.


Same here -- no problem with the Maule for me.

I think follks like to blame things for their own issues
-mis aligned
- hard to handle
-some just do not have the feet to eye co-ordination either.

I see it all the time - thousand of dollars spent on tailwheels
landing gears etc etc
converting to trigear

I never had a issue with tube gear or Maule tail wheels

[airlina]

I have used the Maule tundra tailwheel on my Series 5 for 700 hrs and have never had any issues with mine as well. I do the required maintenance annually and keep it lubed well. So far so good. Bruce N199CL

[t j]

No problems with my Maule tail wheel unlocking except when I want it to. I had no tail wheel experience when I built my Kitfox and the tail wheel was a mystery to me. A friend with lots of tail wheel hours showed me how to rig it.

First couple flights My kitfox was one of those "Squirrley as all He..." tail draggers. Aligning the main gear cured that and it became one of the tame ones.

To unlock it I need to to be moving slowly forward, push the rudder pedal all the way, and "Stab" that brake just as the pedal hits the stop.

A couple years ago I found this short video on tail wheel rigging. It confirmed what my tail wheel friend had showed me.
https://www.youtube.com/watch?v=QtokU8mIDQk

[KFfan]

https://www.youtube.com/watch?v=QtokU8mIDQk

Thanks t j
I had seen that video but could not find it in my "bookmarks".
It is there now!

[n85ae]

I'm with Maxwell ten years on my Maule and NEVER had a problem, and I
don't see why I would either. It is a bone simple device.

I'm a skeptic about Maule Tailwheel as Problem.

Regards,
Jeff


Just to give a voice to those with Maule tailwheels that "behave".

I have had 2 and not had any problems. Just got lucky, I guess, since I did not know I needed to check them.

One on a Maule M7 235 (about 150 hours).

One on the KF for 700 plus hours now without any problem.

I bet I'll check mine at next annual.

[av8rps]

Ok, so again, this is why this my point about maule tailwheels is so hard to get across. I specifically said that I know some have had really good luck with them. But others haven't been so lucky.

Case in point; I have a Kitfox project in my garage that has been seriously damaged in ground loop accidents 4 times. The guy that bought it last ground looped it right after purchase bad enough to mess up the wing and the fuselage, ironically had flown a Luscombe for years before buying tbe kitfox. And the guy that sold it to him had a decathalon and a Pitts, and told me that kitfox was the hardest tailwheel airplane he'd ever flown. He was able to get rid of it before ground looping it, but the original owner wrecked it the three other times (severely enough to need to replace horizontal stab and elevator, wing tips, struts, etc). But ironically, no one ever changed the tailwheel from the original maule. So when I got it the first thing I did was to check it to see if it would unlock with the fuselage on sawhorses. And sure enough, full pedal either way unlocked it easily. Very easily. Oh, and the springs were not too tight.

So using just that Kitfox as an example, were all three of the pilots just not skilled enough to handle this little ol' Kitfox? You can think what you want, but I know what I think. I've experienced a messed up maule tailwheel that made an Avid Flyer pretty much impossible to land (described in detail in my previous post). But by just removing the swivel feature of the tailwheel, that same Avid became easy to land. Oh, and I'm not afraid to defend my tailwheel skills either as I have flown a lot of different tw aircraft in my lifetime and essentially grew up on them. And fwiw, I have never ground looped one. So I know when I can't land a docile little taildragger without the risk of wrecking it, there's something wrong with the airplane, and not me.

For those of us that aren't having issues with the Maule to even subtley imply it is probably poor pilot skills causing the problems others are having I believe is doing a disservice to our fellow flyers.

So rather, how about we do an experiment to get to the bottom of this? How about the guys that have had no issues with their Maules on their Kitfox put the tail up on a stand and see if they can break the lock to swivel by just pushing the rudder pedals full defection left and right (simulating as if you are landing in really gusty crosswind conditions). And also, if they don't unlock with just rudder pedal movement, tell us how tight or lose you have your springs set up.

I'd love to get to the bottom of this, as after searching the net I discovered there are other aircraft types having similar issues with the Maule tailwheel.

[t j]

I am going to do the saw horse test. My plane is folded up on the trailer right now but condition inspection is due soon so I need to get it done.

I have friend that completed building a Model 2 Kitfox a couple years ago. He is an accomplished tail wheel pilot but has problems with his kitfox. He has ground looped it several times and always says he doesn't know why it happened. I keep telling him it is because he isn't paying attention to keeping it straight. I'll check his maule tail wheel when I get a chance.

[n85ae]

A lot of Kitfox's have incorrect tailwheel angle, and compensate for that with
chain tension, and end up probably with all kinds of poor behavior. I milled a
wedge to adjust the angle of my tailwheel on my spring and that helped a lot
with basic handling, and allowed me to run with reduced chain tension.

There's a lot more to tailwheel than just the "Brand", I think you could set
up a Scott poorly, and spend a lot more money to boot, than a Maule ...

I still think the Maule is a fine tailwheel, and I don't buy the poor design
idea at all. I think more likely any fault of Maule tailwheels is that they
were simply not setup correctly in the first place by whoever built the
plane.

There is also the issue that a lot of "fine" tailwheel pilots, aren't, and when
humbled by a groundloop it's easy to blame something. I'm not saying this
is the case exactly here, but I don't buy the Maule tailwheel as simply
being bad.

I run mine with the anti-shimmy friction springs removed, and my chains
are "just" taut, but with no tension on the chain springs. My rudder pedal
pressure is light, and that I've NEVER had the tailwheel bust loose from
an inadvertent unlock.

Oh, but indeed I HAVE groundlooped the plane, and did a spectacular 270
degree tire screeching turn on 8.50x6's tires right in front of the airport
restaraunt at lunch time on a Saturday as well. Which was my fault and
not the tailwheel. I'd be tempted to blame the tires, but I'd rather just
suck it up and say - I screwed up.

Jeff

[jrevens]

Ok, so again, this is why this my point about maule tailwheels is so hard to get across. I specifically said that I know some have had really good luck with them. But others haven't been so lucky.

Pilots have had bad luck with every kind of tailwheel made. I was always a great fan of the Scott 6" wheel (34B/2000), but I had one bite me once when it unlocked on takeoff roll with a strong crosswind. The tailwheel was worn out and I was stupid for not paying enough attention while exercising my superior piloting skills. :rolleyes: The Maule will not unlock when you don't want it to if it isn't worn out & if it is set up properly. By set up properly, I mean that full rudder deflection doesn't make the wheel reach the angle where it releases, and it requires sideways force to move it a small amount further to the unlocking point. On some airplanes that might not be possible without changing the amount of rudder travel or the control arm lengths on either the rudder or the wheel. You need to be set up so that you do not reach that break-free angle with full rudder deflection. If you get a bad wheel that doesn't break at the same angle each time, then you should rebuild it or return it for a good one. The Aviation Products tailwheel, as it comes from the factory, breaks at too small an angle for my set-up, so I machined the groove that the locking key runs in a little larger, increasing that angle. I don't care for the Maule because I think that the quality of manufacturing has not always been good... that is my opinion. The one that failed during the fatal accident with Ken Brock broke apart - the arm that the axle is attached to broke. I have heard that they may have had some bad parts at some particular time. Additionally, the wheel is kind of heavy & hunky. Again, that is just my opinion. I'm not trying to belittle anyone's abilities as a pilot, but you have to monitor it's condition, be aware of how the wheel works and set it up properly, whatever that takes.

[Greensuiter86]

Ironically, I flew to a newly found friends grass strip yesterday to find out he lost control of his newly acquired Mauled M5 and went thru some of his high tension fencing, caught the wing and horizontal stab on a fencepost $$$ ouch! No human damage, but the plane will require a significant rebuild. He thought he just "lost it a bit" on landing, but when I asked if we could check his tail wheel he obliged. It's a Scott, and go figure it unlocked with rudder deflection... btw, he flies for one of the big cargo airlines and has several thousand hours in all types of airplanes to include tail draggers. Just goes to show even very experienced pilots that may not be familiar with the "nuances" of a particular setup or model can get bit just like the rest of us...and be left questioning his or her piloting skills. When the problem really lies in preventative maintenance and knowledge. Another reason to credit this forum for being a great source for discussion and expanding ones knowledge base freely! Great resource!

[jrevens]

With the Scott 6" wheel you have to maintain spring tension on the arms to keep it locked until it reaches the angle where one of the arms is forced back, causing it to unlock. Loose springs are not good with a Scott. That's the 6" wheel - I'm not sure how the 8" wheel works.

[N981MS]

All of this discussion is quite interesting and enlightening.

Something that I previously assumed must not be true. I assumed that if the tailwheel were to break free and be sideways on landing that it would not be an issue. I assumed that it would snap to attention and straighten up immediately on touching down on the runway.

Also, I think I remember watching some bush pilot videos in which they intentionally had there tailwheels setup to be always "unlocked". Maybe they wheel land to a full stop or it is only on a specific airframe they can do that.

FWIW

[n85ae]

If the tailwheel angle is correct (i.e. the vertical axis of the pivot) THEN
the tendency of the tailwheel is indeed to self-center, if it isn't then the
tailwheel wants to keep on turning, which is exactly why with a tailwheel
with incorrect angle you have to run tight springs to eliminate chatter
and if it unlocks you are going for a ride.

Jeff.


All of this discussion is quite interesting and enlightening.

Something that I previously assumed must not be true. I assumed that if the tailwheel were to break free and be sideways on landing that it would not be an issue. I assumed that it would snap to attention and straighten up immediately on touching down on the runway.

Also, I think I remember watching some bush pilot videos in which they intentionally had there tailwheels setup to be always "unlocked". Maybe they wheel land to a full stop or it is only on a specific airframe they can do that.

FWIW

[jiott]

Herman Pahls, if you are following this discussion you might chime in. I believe you told me that you have flown an earlier model Kitfox for many years with the tailwheel fully castoring (no chains at all). Also I believe you mostly do wheel landings. What brand tailwheel was it?

[av8rps]

Ironically, I flew to a newly found friends grass strip yesterday to find out he lost control of his newly acquired Mauled M5 and went thru some of his high tension fencing, caught the wing and horizontal stab on a fencepost $$$ ouch!.....snip, snip....... Just goes to show even very experienced pilots that may not be familiar with the "nuances" of a particular setup or model can get bit just like the rest of us...and be left questioning his or her piloting skills.... Snip

I completely agree that any pilot can have a problem like your friend had in his Maule. I have a friend that had a beautiful 170 Cessna tailwheel that he flew actively for 26 yrs, and one day right after the runway at his local airport was repaved he landed and the tailwheel caught the edge where the two halves of the new asphalt came together, causing the tailwheel to shimmy uncontrollably and off the runway he went ending up in a groundloop that totaled his beloved 170 :( So that's another good example, as well as a good reminder, that it can happen to any of us.

But going back to the basis of what I posted earlier about that Avid Flyer with the brand new Maule tailwheel that I couldn't land UNTIL we disabled the full swivel feature; Here we had an airplane that was so difficult to land that every attempt made me think more that I was going to wreck the airplane just getting it back on the ground (I tried a couple dozen times over a period of about 3 hours - and each time it was just as scary as the first), so it wasn't like it was just a botched landing approach. It was every time I tried to land it. But by just disabling the tailwheels' ability to full swivel, it went from impossible to easy (or like an Avid or Kitfox should land). Saying the change was dramatic would be an understatment.

Now I really don't mean to belabor the point about this one particular airplane, but it makes a really good example of the problem I'm trying to explain our fleet may have (at least some may have) as it was the same airplane on the same day, with the same pilot, and the same tailwheel. The only difference was not allowing the tailwheel to full swivel. So that's why I'm so suspect of the Maule tailwheel.

But that's not to say that another tailwheel can't have the same problem. I personally think that any tailwheel capable of swiveling can have this problem, especially if not set up properly.

But as we are probably all learning here, setting up a tailwheel properly can appear to be some sort of a special art or science. I've not found the manufacturer (Maule in this case) to be offering us readily available, well described set up instructions. But maybe I'm missing something? I did a web search for such and all I found was people having problems with Maule tailwheels, many similar to my experience. I did find some information from individuals giving their opininon, but in reality I learned more from this thread than any of that (more proof that this forum truly is great!).

But what about the poor guy that has built a new kitplane and just bolted on his tailwheel and wants to go fly? Is he supposed to know that you may have to re-invent / re-engineer the thing if you want it to work properly? Is he expected to know all the things we have discussed here relative to privot angle, spring tension, rudder throw specifics, etc? I don't think the average guy building an airplane would begin to know all that. He's just trying to build an airplane and then go fly it. And honestly, it shouldn't have to be this difficult. IMHO, you should be able to bolt it on and go fly. Unfortunately that's not the case for many, as some work that way, and some don't. For the poor guys that aren't lucky (like my friend with the Avid wasn't), I wonder how many have wrecked their airplanes, or just scared them off from ever flying any kind of a taildragger?

It just shouldn't be that hard to sort this thing out in my opinion. But I am really glad to see people sharing their knowledge by posting to this thread. At minimum this can help those that have found this forum and are struggling with their airplane. But it sure would be nice if there was an easier way to get the information to them before they have to experience the problem, or wreck their airplane, and their confidence.

Paul

[Greensuiter86]

Paul I think you hit it on the head. My buddies Sky Raider was damaged in shipment from California, when all was fixed I became the guinea pig as I had the most experience with flying taildraggers...(and the largest set of testicals not connected to brain matter). Taxi was great, but on the runway it was a nightmare. I checked the mains to find out the right gear was toed out over an inch. When that was fixed the owner ground looped it and collapsed the gear. Partly from his inexperience and wanting to "jump in and go" expecting it to behave like the champ he'd been taking instruction in. After flying the Champ for comparison I let him know how much different they really are, (the flight also cemented my disdain for heel brakes cable or hydraulic). I think the combination of heal brake AND a potentially poorly set up or worn tail wheel is a recipe for disaster for new pilots. And let's face it LOTS of new and prospective pilots are attracted to this model aircraft for all the right reasons. But IMHO and many others, these are great little planes as long as you have some experience with lightly loaded short coupled aircraft. In my own admission I was oblivious to this potential hazard, and have been what I consider "lucky" that I've been able to fly so long without a major tail wheel incident. Like others here, I just assumed the plane came with it mounted and it worked. Yes I did some research when I changed from stock to matco on the Rans, but only was aware of the basic setup instructions, not of how potentially devistating it could be if it were to unlock in flight. Color me educated...thanks guys! Stepping of soapbox now...

Jay
N627C

[jtpitkin06]

Just what is the mysterious force that allows the tailwheel to unlock in flight then swings the tailwheel 90 degrees forward into the slipstream, and how does this mysterious force prevent the tailwheel from going into trail and centering at the moment of touchdown?


Just curious.

John

[jtpitkin06]

(http://www.matcomfg.com/TailWheelSteeringFlashVideo-idv-3740-13.html)
Matco's recommendation on tailwheel release. On and off the ground.

http://www.matcomfg.com/TailWheelSteeringFlashVideo-idv-3740-13.html

http://www.matcomfg.com/TailWheelGroundReleaseFlashVideo-idv-3741-13.html

[t j]

Just what is the mysterious force that allows the tailwheel to unlock in flight then swings the tailwheel 90 degrees forward into the slipstream, and how does this mysterious force prevent the tailwheel from going into trail and centering at the moment of touchdown?


Just curious.

John

Forward slip with rudder pedal to the stop could unlock it if not rigged correctly. Not sure what happens in the air but on the ground I have to use opposite brake and swing the tail to lock it back up.

[av8rps]

(http://www.matcomfg.com/TailWheelSteeringFlashVideo-idv-3740-13.html)
Matco's recommendation on tailwheel release. On and off the ground.
(videos)


Unfortunately, the video doesn't show how the swivel reacts to just moving the rudder pedals alone. But then again, I can't imagine why any manufacturer would want a tailwheel to unlock in flight.

I agree that it seems somewhat mysterious that a tailwheel will cant to one side or another, rather than following the airflow. But it will. I'm guessing that sometimes it will follow the airflow, so nothing is noticed out of the ordinary. But when it doesn't follow properly and ends up canted in one direction or the other, you'll know it as soon as the tailwheel hits the ground. I'm thinking when the tailwheel does flop over one way or another, it might just be moving because the airplane is tipped /banked one way or another, causing the weight of the tailwheel to flop over in that direction. But that's just my idea of what might be happening.

I have noticed the tailwheels that are operated unchained by back country pilots typically have a lot of resistance, which I think keeps them from flopping over in flight. Or it might just be that they can get away with what the normal guy can't because they land so much slower, and almost exclusively use wheel landings in an effort to protect the weakest part of their planes (the tail).

In consideration of all this tailwheel discussion, here are two videos that challenge the typical tailwheel ideology;

http://vimeo.com/61152184

http://www.youtube.com/watch?v=ucdb0TKu3rk

[t j]

I did the sawhorse tail wheel breakaway test today. I am one of those that has had no problems with my maule tail wheel breaking loose except when I want it to. To break it loose I need to be moving slowly and push the rudder pedal all the way and "Stab" that brake when the pedal hits the stop.

Doing the sawhorse test the tail wheel does not break loose in either direction when the pedal is pushed to the stop.

Then I pushed the rudder with one hand while pushing hard sideways on the wheel with the other hand. It broke loose in both directions when the rudder horn was about 1/16" from the stop.

I looked back through my builders manual and notes. The manual says to file the rudder stops to get 30 degrees deflection in each direction. At about 25 degrees the cable on the opposite side would hit the stop so I called the factory. He said 25 degrees would be fine. I filed the front of each rudder stop to clear the cables and left it at 25 degrees.

Tail wheel breaks free with side pressure here
7741

Front of rudder stop filed down to clear cable on opposite side
7742

[tomec]

7753 no more trouble

[cap01]

what is it ? did it have a fairing at one time , is that what the holes in the yoke are for ?

[tomec]

locking tailwheel, I do have fairing for it but not going to use it:, land like a trigear

[cgruby]

I just can't stand it any longer. Although I don't consider myself the Bevo Howard of tail wheel airplanes, a few thing I have observed in the 60 years I've been flying. Tail-wheel airplanes that are "squirely" on landing can usually be attributed to:
1) a very aft cg
2) misaligned landing gear (personally I like the wheels adjusted straight ahead)
3) crappy brakes , such as my KF.

I have never flown an airplane with a properly position main gear that ever exhibited uncontrollable characteristics. I've flown full swivel tail wheels which required brakes for steering, with no big problems.

If you want squirelyness, try an N3N Stearman with a misaligned gear and a non-lockable tail-wheel. You had better have good brakes and you really need to use 'em sparingly.

I don't know the answer to all the points brought out here, but I'm inclined to question gear alignment and lackluster brakes as ranking pretty high on the list.

I'm relatively new to the Kit Fox and am still trying to find the sweet spot in all my landings. I have made some real zingers, but have never felt the airplane was going to ground loop. You can't be afraid to get on the brakes if you run out of rudder control, but use 'em sparingly. Anything is permissible to maintain control.

Just my $0.02 worth.
Cheers,

[jrevens]

I sure do agree with you, Chuck. I've only been flying taildraggers for 40 years, and the one time a crappy tailwheel got me was because I screwed up and didn't use the brakes quick enough.

Wheel alignment is a huge factor. When I test flew my Thorp T-18 24 years ago, I wasn't sure I was man enough to fly the thing again. It was a beast! I rechecked the wheel alignment and corrected it to straight - no toe in or out. I knew better but somehow screwed up when I set it the first time. The difference was amazing - made a *****cat out of it. In general, everything happens a lot slower in a Kitfox, & I'll make sure the wheels are straight on mine!

Yep, CG makes a big difference too. Good points!

[av8rps]

TJ,

Thank you for taking the time to do a test on one that doesn't have an issue. Your results are what I would have expected. But I also find your comments and photos about rudder throw very interesting, as it further reinforces what I have suspected all along...

While the NTSB was investigating the crash of that Avid Flyer I previously referred to, even though they initially claimed it was just pilot error (always the default I think), collectively everyone agreed if there was a mechanical issue with the airplane the crash was "probably" caused by too much rudder throw, which may have caused the tailwheel to unlock before touchdown.

So after the NTSB left we tested things further and verified that if the rudder throw was reduced the tailwheel would not unlock (originally it had more than 30 degrees of throw). The builder insisted that Avid didn't specify the travel amount, so he felt that more rudder throw was better.

But knowing what I know today, more rudder throw is not better. It's most likely worse. And your explanation about how your Kitfox was set up makes that much clearer, knowing that they only wanted 25 degrees rather than 30. Maybe that is another reason why some of our planes are ok with the Maule, and some aren't?

But the other thing I've always wondered about that Avid crash is if the tailwheel springs weren't too tight? That Avid tracked on the ground really nice and positive, much tighter feeling than most taildraggers. Understanding more about how these tailwheels need to be set up, I'm now suspect it was a bit too positive (tight).

So maybe the combination of too much rudder throw coupled with springs that were too tight was the problem with that airplane. Unfortunately, at that time none of us were sure about any of this, so the airplane was taken away for rebuilding before we could completely get to the bottom of the problem.


Paul


I did the sawhorse tail wheel breakaway test today. I am one of those that has had no problems with my maule tail wheel breaking loose except when I want it to. To break it loose I need to be moving slowly and push the rudder pedal all the way and "Stab" that brake when the pedal hits the stop.

Doing the sawhorse test the tail wheel does not break loose in either direction when the pedal is pushed to the stop.

Then I pushed the rudder with one hand while pushing hard sideways on the wheel with the other hand. It broke loose in both directions when the rudder horn was about 1/16" from the stop.

I looked back through my builders manual and notes. The manual says to file the rudder stops to get 30 degrees deflection in each direction. At about 25 degrees the cable on the opposite side would hit the stop so I called the factory. He said 25 degrees would be fine. I filed the front of each rudder stop to clear the cables and left it at 25 degrees.

Tail wheel breaks free with side pressure here
7741

Front of rudder stop filed down to clear cable on opposite side
7742

[n85ae]

Tailwheel Caster Angle:

Even if the tailwheel is unlocked, if the caster angle of the pivot is correct,
THEN the airplane will will land perfectly normally ... Since the correct
caster angle will make the tailwheel straighten right out.

It would only ever have a tendency to make the airplane turn, if the
caster angle is incorrect.

So I would assert that if an unlocked tailwheel is causing the plane to
go off course, then the caster angle of the tailwheel is incorrect.

The exception to this is if you are countering a strong crosswind on the
ground with the tailwheel, then it unlocks and rudder alone cannot keep
it straight.

Jeff

[av8rps]

You know Jeff, that makes a lot of sense. I think that might be another piece of this puzzle.

Personally, I am beginning to believe the issues some of us have experienced were probably related to caster angle, spring tension, rudder deflection, gear alignment, or any combination of all of the above.

More and more I'm starting to think that someone really needs to make it much clearer to builders and flyers just how critical any or all of these things can be to sucessfully operating a tailwheel airplane...

It would be nice to see the tailwheel manufacturers do a better job at providing that information proactively, rather than to let some learn the hard way...:confused:



Tailwheel Caster Angle:

Even if the tailwheel is unlocked, if the caster angle of the pivot is correct,
THEN the airplane will will land perfectly normally ... Since the correct
caster angle will make the tailwheel straighten right out.

It would only ever have a tendency to make the airplane turn, if the
caster angle is incorrect.

So I would assert that if an unlocked tailwheel is causing the plane to
go off course, then the caster angle of the tailwheel is incorrect.

The exception to this is if you are countering a strong crosswind on the
ground with the tailwheel, then it unlocks and rudder alone cannot keep
it straight.

Jeff

[Av8r3400]

The reason for my ground loop was tailwheel shimmy, which caused the wheel to unlock.

The shimmy was induced by a sagging tail spring, which caused the king pin on the wheel to have an excessive positive caster.

Look at this helpful photo…

http://pierceaero.net/techdata/tws.jpg

[KFfan]

A quote from Matco site:

"The assembly should be mounted on the flat spring so that the pivoting axle is as close to vertical as possible when the plane is loaded".