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Jim Heffelfinger
02-28-2012, 03:59 PM
This was asked in the old forum with lots of non specific answers. I will ask it again.
Are tail wheel springs necessary? Could I go with cables directly to the wheel steering connects?
Conditions: tiny single seat former UL, tail weight less than 40#, gross of 500#. Matco 6" pneumatic.

Eric Witherspoon
02-28-2012, 04:15 PM
My Sonex has a rigid link between the tailwheel and the rudder. It's a push-pull link, so I'd say you don't even need a dual pull-pull setup, much less any spring. Gross weight is 1150 lbs, and it will generally have the tailwheel off the ground in the mid 40's mph, though I suppose it's probably rolled into the mid 50's mph no problems.

1657

Dana
02-28-2012, 05:11 PM
Depends on what kind of surface you fly off of (pavement, smooth grass, rough surfaces). No springs at all sounds like a bad idea on anything but pavement or very smooth grass.

WLIU
02-28-2012, 05:56 PM
Springs between the rudder and the tail wheel allow you to deflect the rudder when the weight on the tail wheel and the forward motion of the aircraft resists your foot pressure. If you touch down with the rudder deflected to compensate for a cross wind (with one wing down), the tail wheel will attempt to snap from its deflected position to straight. With no spring in the load path, your foot is going to feel that "kick" a lot more. The spring softens what your foot feels.

Hope this info helps.

Wes
N78PS


P.S. I have flown a number of airplanes that have free castering, non steerable, tail wheels. Worked just fine. A little more braking sometimes, but easier to steer in tight places.

Jim Heffelfinger
02-29-2012, 01:14 AM
Reason I am asking is weight. I have a light engine and most likely will have a heavy tail - That Matco is a sweet piece of hardware but 2 pounds heavier than stock shopping cart wheel. Every ounce saved is pounds not carried in the nose. Is there a lightening suggestion for the Matco? It's rated for 250# - way more than it will ever see. Thanks

WLIU
02-29-2012, 04:59 AM
I know of at least one airplane that uses what looks like a roller blade wheel for a tail wheel. Other than looks, why is the Matco attractive?

A lot depends on whether you will be flying from paved or unpaved surfaces. If you only fly from well maintained concrete or asphalt runways, you can use a smaller and lighter tail wheel than if you regularly land on gravel bars.

Best of luck,

Wes
N78PS

bookmaker
03-20-2012, 03:53 PM
If you don't mind me asking a related question, I will share an idea.

I am looking for sorces of tailwheel LEAF spring stock. Preferably 1 1/4 wide. I am building a full size N 17 and need to fabricate a leaf for a tailwheel.

And for the steering cable springs, consider putting them at the forward end if your tailwheel cables run forward. am considering doing that on the N 17.

Dale

martymayes
03-20-2012, 04:47 PM
Are tail wheel springs necessary? Could I go with cables directly to the wheel steering connects?

I think you are referring to the springs that link the rudder horn to the tailwheel arms. If the tailwheel spring is curved, it gets longer when it's under weight. If you don't have something to change length with the tailwheel spring, something is going to break. If there is no appreciable change in tailwheel spring length as it flexes, no need for springs in the steering linkage.

Racegunz
03-20-2012, 09:02 PM
If you don't mind me asking a related question, I will share an idea.

I am looking for sorces of tailwheel LEAF spring stock. Preferably 1 1/4 wide. I am building a full size N 17 and need to fabricate a leaf for a tailwheel.

And for the steering cable springs, consider putting them at the forward end if your tailwheel cables run forward. am considering doing that on the N 17.

Dale
I made my own from old trailer leaf springs just watch to make sure you don't temper or anneal the spring out of it or it will snap or bend, (duh! kinda obvious but thought I'd mention it)