aars

Guys I need your advice.
I am building a large plane which includes servos in the wings for flaps and ailerons. As you can imagine the distance from the servo to the Rx is relatively large (say 25"-30").
I have read in some places that if the distance is long, it is better to loop the extension wire around a ferrite ring to avoid interference. The ring should be a few inches away from the Rx.
When is this necessary? Is there a specific extension length from which this ring should be used? Do I need a signal amplifier as well? Is it better to change the wire of the servo for a long one instead of using an extension? or using the regular wire and a long extension is OK?

thanks for the input