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  #11  
Old 04-18-2018, 12:54 PM
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DanH DanH is online now
 
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Slack means most tailwheels, if forced sideways, will pop into full swivel. You're allowing the tailwheel fork to swivel farther than the rudder.

Easy test...position your airplane with full rudder applied, rudder horn against the stops. Now push the tail sideways. If it is easy to push into full swivel, or is already released, the slack chains are allowing the fork to turn too far. We want a system which requires a brake tap to force into full swivel.

If tight chains (or a link) is causing the steering to be too quick, the arm ratio is wrong. Simply move the chains or link inboard on the rudder horn, or move them outboard on the fork arm. it will probably fix the aforementioned release angle problem too.
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  #12  
Old 04-18-2018, 01:26 PM
rvbuilder2002 rvbuilder2002 is offline
 
Join Date: Jul 2005
Location: Hubbard Oregon
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Quote:
Originally Posted by DanH View Post
Slack means most tailwheels, if forced sideways, will pop into full swivel. You're allowing the tailwheel fork to swivel farther than the rudder.

Easy test...position your airplane with full rudder applied, rudder horn against the stops. Now push the tail sideways. If it is easy to push into full swivel, or is already released, the slack chains are allowing the fork to turn too far. We want a system which requires a brake tap to force into full swivel.

If tight chains (or a link) is causing the steering to be too quick, the arm ratio is wrong. Simply move the chains or link inboard on the rudder horn, or move them outboard on the fork arm. it will probably fix the aforementioned release angle problem too.
I agree with Dan but I believe that too tight can induce the same problem in (unintended unlock of the tail wheel) some cases.

When the airplane is traveling fwd with the tail wheel on the ground, it has a natural castor tendency to straighten out and align with the direction of travel. This will actually be countering any looseness in the chains and not allow the assembly to move far enough to unlock.
There have been instances where very tight chains are able to rotate the tail wheel far enough to unlock because the rudder is able to over come the natural castor force. This is particularly common with some installations of the single steering link because it doesn't cause an equal amount of tail wheel steering angle in both directions.
I know of one ground loop accident that I believe was cause because the tail wheel unlocked with full rudder input, with a steering link installed.
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  #13  
Old 04-18-2018, 01:30 PM
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donaziza donaziza is offline
 
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Location: Atlanta
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Quote:
Originally Posted by DanH View Post
Slack means most tailwheels, if forced sideways, will pop into full swivel. You're allowing the tailwheel fork to swivel farther than the rudder.

Easy test...position your airplane with full rudder applied, rudder horn against the stops. Now push the tail sideways. If it is easy to push into full swivel, or is already released, the slack chains are allowing the fork to turn too far. We want a system which requires a brake tap to force into full swivel.

If tight chains (or a link) is causing the steering to be too quick, the arm ratio is wrong. Simply move the chains or link inboard on the rudder horn, or move them outboard on the fork arm. it will probably fix the aforementioned release angle problem too.

Thanx Dan, I like your answer. I have a "lot" of slack in my chains, so your first answer is easy to do. Your 2ed answer, "if chains too tight", I wasn't a builder or mechanic, so I don't understand, but I "do" have a mechanic, and I'm sure he will understand.
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  #14  
Old 04-18-2018, 02:06 PM
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DanH DanH is online now
 
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Quote:
Originally Posted by rvbuilder2002 View Post
I agree with Dan but I believe that too tight can induce the same problem in (unintended unlock of the tail wheel) some cases.
Agree...if the arm ratio is wrong.

It can't unlock if it doesn't reach the release angle.
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  #15  
Old 04-18-2018, 02:10 PM
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Mike S Mike S is offline
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Quote:
Originally Posted by DanH View Post

It can't unlock if it doesn't reach the release angle.
That is for a correctly installed, maintained and functioning unit. These things do require maintenance.
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  #16  
Old 04-18-2018, 04:43 PM
Jpm757 Jpm757 is offline
 
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I have always kept positive tension on all of my tailwheel springs, I think it reduces wear and allows for more precise control. I installed the Flyboys Rocket Link on my new -7 and I love it! My buddy put one on his -8 and he too is sold. Only 100 hrs since new, we'll see how it holds up.
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  #17  
Old 04-18-2018, 08:16 PM
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RV6_flyer RV6_flyer is offline
 
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Quote:
Originally Posted by Ironflight View Post
Tight chains vs slack in chains is a religious argument that I believe started between Wilbur and Orville.....I have great friends who are great (and we’ll respected)pilots on both sides of the argument. Both obviously work. Personally, I like tailwheel links, but I fly lots of planes with chains - loose and tight -and I just adapt.
I have read all the posts in this thread. I agree that there will be a personal preference on how tight or how loose. Yes one gets use to different adjustments in different airplanes or at least Paul and I do.

I found that the chains furnished with the kit stretch and get loose after 300-hours. Taking out one links then makes it too tight for me. New chains work well till they get time on them and then stretch again.

I changed out the chain for cables on the standard "compression" springs and that was over 2,000 hours ago. Have flown other tailwheel airplanes and although not the exact way I like it on my airplane, there was no issue adapting to the difference.
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  #18  
Old 04-19-2018, 06:57 AM
drycreekrv drycreekrv is offline
 
Join Date: Sep 2008
Location: Houston, Texas
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Default After 25 yrs......

It's worth considering....(for tail wheel RV's) --- that little tail wheels are
sensitive to every little bump it runs into. Tight Springs/Cables makes
the rudder sensitive as well. Ever noticed some RV's who rudder wiggles
with every movements the tail wheels feels... almost rattling around all
the time. I've found over the years.... loose chains help with the overall
wear over the years. Iron Flight said it right..... it's easy to adjust.
Replacing a worn out rudder is a lot of work.
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  #19  
Old 04-19-2018, 01:59 PM
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dougweil dougweil is offline
 
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On both my RV-4 and RV-7 I have used Citabria tailwheel springs. I have the chain length set so they are "just" tight (or no slack). I do replace those cheap tailwheels every couple years as I think they steer funny when the rubber gets worn down flat. With this arrangement I feel the steering is positive but not twitchy. I don't care for slack in the chains which creates a "dead" spot in the steering.

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  #20  
Old 04-19-2018, 02:11 PM
Christopher Murphy Christopher Murphy is offline
 
Join Date: Feb 2007
Location: colorado
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Default Make too much of it..

Ive flown my rv4 with nothing connecting the tailwheel to the rudder several times..I like my chains loose so the rudder steers until about half deflection before the tailwheel gets pulled by the chains..

Cm
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