Why hang this on high voltage power lines? (ANSWERED)

[chris_leyson]

I was going to say Stockbridge dampers do the same job but Jitter beat me to it.

[David Hess]

I have only seen or maybe notice the triangular wing type before.



Instead of radar reflectors, I have seen what look like large colored beach balls attached to the lines making it easier for aircraft to see them.

[CatalinaWOW]

This may be a test area, but another possibility exists.  Unless the towers are infinitely stiff ( ) the lines are coupled, so damping one line has an effect on the others.  One may be all that was necessary.  The triangular slotted dampers are quite common on telephone and distribution wires in the US.  Numbers vary widely, from none to as many as half a dozen on a single wire segment.  Presumeably these are fitted on an as needed basis with no analysis beyond looking at the wires or checking failure records for a line.  The variations in number would reflect a combination of variations in local conditions and attitudes of the field guys installing them.

The aerodynamic dampers seem to have completely taken over from another older technology that is still seen hanging from wires, a weighted spring/oil dashpot.