[LINK] An Overhead NBN

[Karl Auer]

On Fri, 2013-11-08 at 09:25 +1100, Jan Whitaker wrote:
> Common sense tells me that putting non-destructable es can l(low? 
> destructable) components along poles wouldn't be any different than 
> putting them underground EXCEPT for the danger of being crashed into 
> and broken by some other thing, like a car.

Poles take lightning strikes. Poles fall over and cause damage when they
do. Poles are unsightly. Poles (as you say) are additional things to be
run into. Poles can be easily climbed by the young and the insane. Poles
are obvious, they can be found easily for purposes of attack (whereas
trenches disappear quite quickly; pits are not obvious; pits can be
locked). Poles, insulators, mounts and the cables themselves can be shot
at (very common in rural areas). Suspended cables can be easily reached
with thrown objects esp. shoes. Suspended cables can be hit by other
things - high trucks, extended ladders, birds, aircraft, kites etc. When
a pole fails, for any reason, the cables pose a great danger, especially
if electrified. Failure in a trench or pit is generally harmless. Poles
are vulnerable to extreme weather, especially wind and (in some
countries) ice. Poles block some land uses - can't run or drive through
them, can't build over them, can't build too near to them etc etc. You
can't plant trees near the poles or near the path of the wires.

Underground has some similar disadvantages, but in general far fewer, in
particular it's not unsightly and they are invulnerable to just about
everything except an earthquake (and maybe flood).

Regards, K.

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Karl Auer (kauer at biplane.com.au)
http://www.biplane.com.au/kauer
http://twitter.com/kauer389

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