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Re: good news and bad news


I would be most interested in finding out where your cable broke. My
guess is it broke where most of these cables break (when they break) and
that is at the butt end of a nico press.

As it is with electrical wire and terminals, if the cable (wire) is able
to flex at the point of compression, there is an established fracture
point for the outer wire strands to break (fray), thus making the cable
itself weaker. Using 3/32" cable, while offering greater tension loads
initially, does nothing to prevent this 'splintering' away of the outer
strands at the fracture point. It merely allows you a longer period of
time before the cable finally breaks. I cannot conceive the 1/16" cable
breaking anywhere in the middle due to tension loads. After all, the
nylaflow tubing is imbedded in foam. If the tension were to become too
tight, I would think the bend areas of the nylaflow tubing would compress
the foam walls providing some 'sponge' for the cable itself. 

One of the drawbacks to the internal rudder horn is that you cannot
inspect the cable / nico press location prior to every flight. It is very
important that you remove the rudder for this cable inspection during
every annual, possibly even every 100 hours.

One remedy to this situation is to provide a bearing for a friction free 
pivot point between the rudder horn and the cable. As you well know,
though, space is at a premium in this location and safely securing a
cable to a bearing isn't exactly easy.  We have discussed this a lot at
the factory and unfortuantely we have not come up with a practical
solution other than good visual periodic inspections and good preflights.

Knowing that things could have been a lot worst, I am glad  you and your
plane survived with only minor damages. 


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