Tailwheel steering - better turning to the right

Kyle Wolfe · Post by **Kyle Wolfe** » Thu Jan 15, 2004 11:11 pm

Success at last! We pulled the tailwheel apart and took a close look. The spring (#18 on the aircraft spruce diagram) was a shade too long. This caused the spring to not "lock" into the arm assembly thereby allowing the arm to simply slip past and not turn the wheel.

We shortened the spring and reassembled and everything works just fine.

All parts were new, but the spring was just a bit too long. Go figure.

zero.one.victor · Post by **zero.one.victor** » Fri Jan 16, 2004 12:50 am

As I recall,there are 2 spacers or shims that go in the same space as the spring,& are pinned in place right along with it. If those were in the wrong place--aft of the spring instead of forward of the spring--might that cause the spring to appear to be too long? Unlikely,but worth checking out. There's an exploded view of the 3200 in the Univair catalog,I think the Spruce catalog has one too.
I have had the trouble of the tailwheel releasing too easily--it turned out to be a fatigued spring. Also had the trouble of the t/w not releasing easily enough--that time,it was a burred end on the spring binding in the steering arm notches,making it too hard for the pawl to properly cause it to release.
these Scott tailwheels are a pain in the patooty! Unfortunately,they're the best option--the other tailwheels are even worse!

Eric

wa4jr · Post by **wa4jr** » Sun Jan 18, 2004 4:46 am

Well George makes a really good argument for the retention of the original tension springs...but his comment came after I ordered my compression springs and now they are in place. I still have the tension units and will put them back on if I don't like the way the compression springs work. As an observation, with a new tailwheel main leaf installed as of last year, when I lift the tail to put it on the approved milk crate + 2x4s, I don't see the tailwheel drop one little bit. I adjusted my chains for light tension in flight, and then when I put the tail back down, the chains seemed just as tight. Now I may load up the family and find that the chains have become slack, which I will have to correct. I was just surprised not to observe any downward movement of my tailwheel assembly when I raised the tail

wa4jr · Post by **wa4jr** » Fri Jan 30, 2004 2:18 am

I loaded up the family for the first XC since the new springs and chains were put on. Tension was just fine. When I land in Linden NJ I see that both chains are hanging loose resulting in almost no pull on the tailwheel horns for steering. Could the links in the sash chain have streched so much? I'm going to have to take another link out of each chain to restore a bit of tension on each compression spring. Anybody else ever have this problem with new tailwheel steering chains?

zero.one.victor · Post by **zero.one.victor** » Fri Jan 30, 2004 7:07 am

If you have some of that chain left over from your installation job,compare it to the "stretched" chain that's on your airplane. I would guess that the chain didn't stretch,but maybe the spring relaxed a bit?

Eric

wa4jr · Post by **wa4jr** » Sat Jan 31, 2004 7:45 pm

I'll check it out Eric and see if the chain did stretch by comparing a few new leftover links. I did not notice any deformation of the links when I looked at them, but then with the temps in the single digits and a wind blowing, I don't stand around too long to look. What bothers me a bit is the spring relaxing. As they are, these compression springs don't have a lot of "spring" in them before they bottom out and I am worried what the effect would be say going from full right rudder turn to full left rudder. The compression springs may tend to bottom out and then yank on the tailwheel horns with no cushioning effect. I'd be concerned about the long term stress on the parts involved. The more I think about it, the more I think the constant tension of the original springs may be better than the possible "bottom out and jerk" operation of the compression springs

lcranton · Post by **lcranton** » Sun Feb 01, 2004 3:49 am

John, I personally do not think compression springs are a good idea for exactly the reason you stated. I know of two people that have tried to use them and both had the same results - a bent rudder horn. When the compression springs reach their limit they transfer all of the azimuth shock and loads from the tailwheel to the rudder horn. Some aircraft have very strong rudder/tailwheel steering horns but not the 170. IMO the original Scott tailwheel springs seem to work the best.

Larry

Post by **GAHorn** » Sun Feb 01, 2004 8:50 pm

This is exactly the conern I was trying to express in my earlier msg in this thread. The compression springs have potential to cause physical damage the original springs do not.