Hey Phil If you have no tail wheel time, I would suggest you get some with an instructor. Tail draggers have a habit of swapping front and back. If you have the stock single rod to steer the tail wheel, change it to chains and springs like the big boys. As you put weight on and off the tail, it changes the steering. You can ask skyblazer what happens. They say these plane are too squirly to fly off pavement. They handle much better than my chief. Bit not with that single rod. Me and skyblazer always flew off pavement. Skyblazer had serious problems till he changed his. I had chains and springs from the beginning and never had any handling problems. There was one fellow on here that was terrorized to fly off pavement. It took me a long time to convince him. Then when it worked he told everybody how good his idea was, LOL. At least he fixed his plane. Bob
Bob, I have heard this said before too, but never really understood why keeping the rod is a bad idea. Is it because the rod has no spring in the linkage to modulate excessive steering inputs ? Thanks
I just moved this topic to a separate thread, so it does not mess up with Phil's build thread.
I have a steel rod ( 1/4 inch thick ) to steer the tail wheel. I used steel in place of Aluminum rod suggested in the build plans, mostly because there have been reports of these rods shearing and breaking in usage.
Yesterday while taxiing on the airfield pavement, ( had some cross wind too ), I found the tail wheel skidding over the pavement on rudder application at speeds of around 15 to 20 mph before tail was lifted. I am guessing the wheel was getting too much steer input from the rudder pedals and was skidding the pavement at an angle. May be there was no way for the excessive input to be dampened by the rigid steel rod.
After a few such skidding incidents, each indicated by a jarring sound from the tail wheel, I got down to inspect the tail wheel, and found its axle burning hot. Thats when I realized that I may need to change the set up to having springs on either side. I read some old threads on this too, but could not figure out why the springs may do a better job.
Hey Kieth No, the rod is not on the same plane as the pivot point of the wheel. As you add weight to the tail the tail wheel spring flexes and the rod pushes the wheel to the right. You in turn push left rudder, when the tail comes up, the plane shoots the the left because you have left rudder in to steer the plane straight. As you normally taxie the plane, any changes in the elevator position changes the load on the tail wheel spring. You end constantly making corrections. This could cause some serious problems at take off or landing speed. Anyone with a single rod having problems taxiing on pavement should modify it for 2 chains and springs. This little plane will taxie as straight as can be with a standard tail wheel steering setup. They are light enough so when you put in some rudder pressure it turns right then and goes exactly where you want it to go. My chief is a lot harder to taxie compared to a minimax. It is a standard tail dragger, LOL. I know there might b some out there that will want to argue the point, so b it. Been there done that and fixed it!!! Bob
Bob, thanks so much for explaining this. I am not sure I understood all of it, but since you recommend to instal the springs as shown in picture, I am going to do exactly that.
Learning to fly a taildragger without instruction is not that hard...I never had any. It’s a matter of developing a reaction with the rudder pedals without thinking about what to do. Always start with the wind down the runway then taxi at a slow speed while reacting to any yaw. At first you will think about any correction but will soon stop thinking about it and start reacting by what you see. After you are comfortable at slow speed increase the speed and practice at that level until you have complete control of the aircraft. This will take some time but you will be surprised at how quick you pick it up. I would not try crosswinds until you are in total control and comfortable with your skills. Of course if an instructor is available consult him.
Monte
Monte, Thanks, that was very helpful. This airfield ( code :18V) usually has some amount of winds even early morning. Direction is variable, but it is rarely straight down the runway. It keeps changing from 10 o' clock to 2 o'clock. I guess I will have to get used to it. There is a cross runway which is turf, but I avoid that due to the thorn issue.
Quoted from Bob Hoskins Hey Keith No, the rod is not on the same plane as the pivot point of the wheel. As you add weight to the tail the tail wheel spring flexes and the rod pushes the wheel to the right. You in turn push left rudder ( right rudder ), when the tail comes up, the plane shoots the the left because you have left rudder in to steer the plane straight. As you normally taxie the plane, any changes in the elevator position changes the load on the tail wheel spring. You end constantly making corrections. This could cause some serious problems at take off or landing speed. Anyone with a single rod having problems taxiing on pavement should modify it for 2 chains and springs. This little plane will taxie as straight as can be with a standard tail wheel steering setup. They are light enough so when you put in some rudder pressure it turns right then and goes exactly where you want it to go. My chief is a lot harder to taxie compared to a minimax. It is a standard tail dragger, LOL. I know there might b some out there that will want to argue the point, so b it. Been there done that and fixed it!!! Bob
Bob, I got what you explained above. Probably just the direction of rudder application in your note may need a change. When the tail spring expands/elongates, wheel turns right, so plane turns left, and you would probably be applying a corrective right rudder. And the opposite sequence when tail spring shrinks. But your explanation makes sense. Thanks
Hi Kieth The explanation is correct. As you put weight on the tail, like holding up elevator as a good tail dragger pilot would do (unless you were taxiing down wind). On take off the pressure on the tail increases, you push in more left rudder to keep the plane straight. You relieve the up elevator to lift off and the plane darts to the left! Them are the facts, LOL. With duel steering springs and chains the problem is completely eliminated. Don't forget we are talking about correcting a misaligned single rod steering system. I can see how it can be confusing. Bob
Bob, thanks for the clarification. I have ordered some parts , so the mod on my tail wheel is not yet done. Also I am looking for a 6 inch tail wheel that may have more traction than my presently installed 3 and 3/4 inch tail wheel. This wheel tends to crab at times when rudder is applied causing a rumbling sound. I also noticed excessive wear on the present tail wheel because of this.
This is just for academic discussion. Can anyone try to guess what happens if we attach the springs on the 2 tail wheel actuate cables, ahead of the steer bar pivot point, so that we still retain the 1/4 inch steer rod ?
Can anyone try to guess what happens if we attach the springs on the 2 tail wheel actuate cables, ahead of the steer bar pivot point, so that we still retain the 1/4 inch steer rod ?
That's an easy question: the tailwheel steering will become a bit less precise.
I wouldn't normally bother to make such a small point in a forum post. I will because it gives me a chance to bang on about how - in practice - there's nothing wrong with the existing Wayne Ison system! It works well.
If you want to experience squirrely steering try a DeHavilland Tiger Moth (I have). They don't even have a tail wheel - just a skid. It has to be said they were primary trainers but the military could have specified a tail-wheel. It shows that the military at that time thought teaching to think ahead is an important part of learning how to handle an aeroplane. Maybe the military had more aeroplanes to replace the ground-looped ones than we have, but I hope you admit there is a point there.
Maybe it was to teach the trainee ground mechanics how to repair an airframe....
I have heard & seen that (most ) just use the springs you can get at Home Depot for storm doors. Others like to spend extra money & get something more "Official" Thats just what I have seen & herd......YMMV....JMHO TTT
It depends which side you have the rod mounted as to which side the plane will turn to when the spring bends. So if yours is mounted on the left, then the wheel will turn to the left and try to turn the plane to the right when the spring bends. If your rod is mounted on the right then the wheel will turn to the right and try to turn the plane to the left when the spring bends.
Antoni,
My UK designated 88 was built from 1990 - 1994 by Barry Crick. It's fitted with the springs and chains, which were either specified by the plans, or by the UK LAA when they approved the design at the time. However, since then I know that the plans have changed, and now the 1030 plans show a single rod mounted to one side.
The reason I know the plans have changed is because on mine station 4 is the seat back, i.e. the back of the seat is fixed and a structural member, however, the 1030 plans now show station 4 as being separate from the seat back. Unfortunately a previous owner managed to lose all the paperwork from the build during a house move, so I can't refer back to the original plans for confirmation of the tail steering fitment, but the current plans show a single rod tail wheel steering set up. This makes me think that the original design had springs, and that the plans were then amended to a single sided rod.
The advantage of springs and chains is that it doesn't matter if the tail spring flexes, the load remains the same on both arms, so the plane tracks straight. It's only the single sided rod that has problems trying to stay straight when the tail spring bends.
It depends which side you have the rod mounted as to which side the plane will turn to when the spring bends. So if yours is mounted on the left, then the wheel will turn to the left and try to turn the plane to the right when the spring bends. If your rod is mounted on the right then the wheel will turn to the right and try to turn the plane to the left when the spring bends.
Bob.Hood,
When the tail spring flexes, AB elongates. Since CD is of fixed length, tail wheel can only turn right due to lengthening of tail spring( not left ). Plane will turn left, so it will need right rudder input to counter it.
I even tried this on the tail spring and got same result. I had assumed earlier that all steering rods are on port side per plans.
May be I am missing something.
I assume I am wrong, because Bob Hoskins also mentions the same thing that you are stating. So I am not contradicting you, just trying to understand why the above explanation I gave is wrong.
Keith Here is your text. "Plane will turn left, so it will need right rudder input to counter it." You got the gist of what happens. With weight on the tail the plane will turn to the right. You in turn have to put in left rudder to make the plane taxi straight. when the tail lifts off the ground, it darts hard to the left!. Now this happens to many varying degrees while you taxi or taking off or landing. Making the plane squirrley. https://www.youtube.com/watch?v=uTzoi2YXtJY (a little long, watch begining and toward end) https://www.youtube.com/watch?v=LmawDnziiKc The last video is what happens with an uncorrected tail wheel. You will notice the pilot handled the situation with out hesitation as to the huge surprise on the first take off. If the link does not work, copy and past into your browser. Bob
Going back a little up-thread, my initial issue was that tail wheel was crabbing sideways during fast taxi when I started applying even small amounts of rudder.
The reason, as I discovered now, was that my tail wheel steering geometry was set towards excessive steer. At full rudder, I had set it for almost 45 to 50 degrees wheel deflection. This was way too much deflection.
I built it like this since I do not have brakes, so I wanted to have enough steer capability while turning tight on the apron. The downside was that even very little rudder application would send the tail wheel turning A LOT, so there was tendency for tail wheel to crab/ skid sideways especially during fast taxiing.
As a temporary solution before I change to springs, I have reduced the tail wheel steer by altering the geometry. Now max wheel deflection comes in at about 25 to 30 to either side.
I will try a fast taxi with the new set up and see if tail wheel still crabs / skids sideways with rudder application.
Will take the plane to the airfield possibly sometime next week.
A picture of the modified tail attached below: ( This is at full pedal deflection. I will clip off excess steer arm length after taxi trials. )
I see what you mean when you say the AB distance lengthens. Because my tail spring is not far off being straight, if it bent upward then AB would shorten, hence my saying that the tail wheel would turn left if the rod was on the left.
You can see my tail spring in the attached photo.
However, if your tail spring is noticeably bent at each end then your AB would indeed lengthen, and the tail wheel would turn to the right.
Puff, thanks , every input is welcome. I will keep your point in mind. This is only a temporary set up. If this mod solves the wheel's sideways skidding issue, then I may redo the whole set up so this extra strip will be removed. ( If not, I will move on to spring and chain set up, in place of rod ).
Keith1100, However, if your tail spring is noticeably bent at each end then your AB would indeed lengthen, and the tail wheel would turn to the right.
True, that is when weight is being exerted on tail wheel.
But when weight is being removed from tail wheel, like during take off, spring contracts in my Max ( opposite to what happens in your Max ), or my spring gets more bent downwards, so AB shortens, so wheel should turn left, and plane right.
But the video from Bob Hoskins clearly shows plane veering to left on Take off.
So the real reason for the opposing theories, (just guessing), may lie in how the tail aluminum spring is rigged in neutral position with no weight on it.
If the spring is NOT bent as in plans, plane will veer left on take Off. If it is exactly per plans, plane may instead veer right on T/O.
But no matter which way the spring is rigged, weight changes on tail wheel should make plane veer from center line in a rod set up. (Not saying it cannot be controlled in a rod set up.) But the logic just may be suggesting a rod set up may make it more squirrely.
Kieth That's called P factor. Normal rotation engines will always need some right rudder on take off. My Nieuport 11, cause it has a VW engine , needs left rudder! the Minimax tail wheel is a whole other ball game. I tried to help, fly safe. Bob
I learned real quick to just fly the tail first... Get the tail up first as fast as possible and keep it there. it helped me. might not help anyone else, tho.
I learned real quick to just fly the tail first... Get the tail up first as fast as possible and keep it there. it helped me. might not help anyone else, tho.
Good advise. Noted, thanks. Bob Hoskins, I got the key points of your Input too, that pavement operations may require a spring and chain set up.
I flew 45 hours in a military tandem tail dragger in 1975 as an aspiring young military pilot trainee. Out of that 14 hours were solo. The plane had a spring actuated tail set up. Never ground looped that plane even once in about 65 to 70 landings (with or without instructor.) Never flown a prop plane after that as we moved on to jets. The 14 hours solo had stall recovery, general handling , one cross country navigation, plenty of aerobatics and one intentional spin and recovery. Quite a handful for a young pilot with less than 50 hours of total experience. They really push you hard in the military. But the Max is a much lighter bird, gross weight being only about a fourth of that military trainer. A little caution is always a good thing. As they say, there are no old and bold pilots.
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