At 10:25 PM 12/4/01 -0800, Dick Flanagan wrote:
...
>For (relatively) short guyed amateur towers under 100 feet the most
>common failure mode is that of a broken guy support from excessive
>horizontal forces. While the failure of a top guy of a multi-level
>guyed tower might constrain the debris radius by allowing top sections
>to fold around lower guy supports, this would still not be the classic
>downward crumple observed in the TV tower.
>
>I dare say if the TV tower had suffered the total loss of one of its
>upwind guy supports, it, too, would have fallen like a giant tree.
Aren't most TV towers, and particularly the really tall ones, equipped with
multiple guy anchors in each direction? Seems to me that doing this with
amateur towers would virtually eliminate the tree-cut-at-bottom scenario by
making sure that the tower remains tethered on the way down.
PS - mine isn't, yet, but I'm thinking of adding anchors for the top guys
that are 15 feet or so further out than the existing anchors.
73, Pete N4ZR
www.qsl.net/n4zr
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