> The 30% or so radius is correct but only for guyed towers. Self-
> supporting towers will fall their full length.
>
Going by memory, what I seem to recall from the previous threads on this was
that most guyed towers fall into the 30% radius, but they can occasionally
fall their full length, usually due to guy anchor failure where all the guys
on one side come loose at once. In this case it would fall in a direction
directly opposite from the failed anchor. And as for self-supporting
towers, all of the failures I've heard of involved "twisting down" (Rohn
HBX-type), or folding over part somewhere near the middle or higher. I
wouldn't think it is very common for a self-supporter with a per-spec base
to pull that base out of the ground, but I guess leg failure at the base
(i.e., rusted) could cause a failure that would lay the self-supporting
tower out full length.
73,
Dave WD5N
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