[Geoff]

I'm considering switching from the screen door chains/springs to the Tail Lynx system for tailwheel steering, but I can't seem to find many details online anywhere. So to anyone who uses them, can you answer these questions?

1) Are they adjustable? By how much?

2) Do they hit the bottom of the rudder at full travel? With my stock chains, I can't adjust them as tight as I'd like because they hit the bottom of the rudder at full travel -- and I've even lowered them using eye-bolts on the rudder horn.

3) Can you provide any close-up pictures of the installation?

Thanks.

-Geoff
RV-8

 

[jbDC9]

1) Are they adjustable? By how much?

2) Do they hit the bottom of the rudder at full travel? With my stock chains, I can't adjust them as tight as I'd like because they hit the bottom of the rudder at full travel -- and I've even lowered them using eye-bolts on the rudder horn.

3) Can you provide any close-up pictures of the installation?

They're adjustable during installation only; adjustment/slack depends on where you drill the holes. You'll see what I mean if you get 'em. Also, if you lift the tail wheel off the ground to make it easier to work on, once you drop the tail and the weight is on the spring it'll add some slack to it, just like the screen door chains.

I haven't noticed them hitting the rudder... not yet anyway. And pictures? Sorry, I forgot to take pics during the install. And the bottom line? Yep, I like 'em! Cleaner and tidier than the screen door chains and no rust. I have just a bit of slack in them and they feel fine.

 

[JonJay]

Reverse the Springs

I reversed the direction of the units, put the springs on the tailwheel side rather than the rudder horn side. This prevents them from hitting the bottom of the rudder. They work either way.
I know of many installed that do hit, but I don't think it causes a problem other than a bit of scuffed paint.
Personally, I like my springs loose. I theorize that it is helpful in a cross wind. Direction control on the ground is not a problem with a little differential braking when necessary. Some like them really tight. Personal preference I guess.

 

[N908RV]

Reverse the Springs and ignore Tail Lynx slack recommendation

I have these and love them. Reversing the springs is the way to go, otherwise they will hit the rudder bottom and scrape it up.

This means that you have to reverse the angles of the bends they tell you to make in the mounting tongue on the spring and the bend in the cable end.

The other item - and this is purely personal preference - is that I would ignore the slack that he tells you to leave - if you follow the directions the springs will be way too loose - even if you like them loose they are crazy loose that way.

What I did was to have the tail up in the air - supported by a tall stool under the aft bulkheads so no weight is on the tailspring rod. Then I made my marks and bends and have it set up so that there is basically no slack with the tailspring in the air. Once you set it on the ground, the weight of the plane bends the tailspring rod a bit and provides the needed slack others talked about.

My thoughts on tight springs - I love them, but I don't keep them tight - just a slight bit of slack. Why? Imagine if both springs were tight and you had one side fail. You may not be able to overpower it quickly enough with differential braking. Both springs failing simultaneously, no sweat. One spring - look out weeds here we come!

 

[JonJay]

My thoughts on tight springs - I love them, but I don't keep them tight - just a slight bit of slack. Why? Imagine if both springs were tight and you had one side fail. You may not be able to overpower it quickly enough with differential braking. Both springs failing simultaneously, no sweat. One spring - look out weeds here we come!

I think your set up makes a lot of sense.

Here is my theory on the tight springs;
On take off roll, there is a short time before lifting the tail that rudder is required to overcome the torque. If your springs are "loose" the rudder does the work and keeps you on center. If your springs are tight, the tailwheel is enganged and trying to turn the airplane or "push" the tail. However, the rudder is trying to keep the airframe straight. Hence, the tailwheel will actually be sliding sideways or be side loaded once the springs bottom out, if they bottom out. As you can imagine, if the tailwheel was not sliding and was "stuck" to the ground, you would run off runway, so it must slide sideways or be side loaded at the least when the rudder is deflected.
I am not sure if this contributes to tail wheel wear as the time you spend in these machines with the tail down on take off roll is pretty minimal, but it makes sense that it might.
I transitioned in a 7 with loose springs. My instructor, Mike Seager (15K hours in RV's or something rediculous like that) told me they where loose to facilitate cross winds landings better. He also seemed to suggest that it probably made little difference.

 

[N908RV]

On take off roll, there is a short time before lifting the tail that rudder is required to overcome the torque. If your springs are "loose" the rudder does the work and keeps you on center. If your springs are tight, the tailwheel is enganged and trying to turn the airplane or "push" the tail. However, the rudder is trying to keep the airframe straight. Hence, the tailwheel will actually be sliding sideways or be side loaded once the springs bottom out, if they bottom out.

Interesting comment Jon.

OT - I remember taxiing around my old Sonerai way back when and it had a single rod (kinda like a Jantzi link, but with no spring in it at all - just a rod) connection from the rudder horn to the tailwheel. And yes, you would skid it all over the place. I finally changed it from the stock Sonerai set up to traditional compression springs and that alleviated the skidding around and made taxiing easier - also gave me a tighter turning radius. Not an RV, but same rules apply here. Mileage may vary.

Best,

Rob

 

[JonJay]

Reversal not recommended

I reversed the direction of the units, put the springs on the tailwheel side rather than the rudder horn side. This prevents them from hitting the bottom of the rudder. They work either way.
I know of many installed that do hit, but I don't think it causes a problem other than a bit of scuffed paint.
Personally, I like my springs loose. I theorize that it is helpful in a cross wind. Direction control on the ground is not a problem with a little differential braking when necessary. Some like them really tight. Personal preference I guess.

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