>
>Crank up towers are safe. They do require adequate maintenance.
>
>I have had my Tristao 71 footer (now US Tower) for nearly 30 years at 4
>locations in two states. It has ridden through 5 tornadoes, 3 hurricanes
>and many wind storms.
>
>In those 29+ years I have replace the wire rope twice, one pully, and the
>winch. I have had a welder on my roof to fix a cross bar sheared off by a
>prop pitch and have cleared out three batches of bees/wasps. The lower wire
>rope broke once bringing the system down, but my use of steel pipe stops
>only let it drop about a foot. Maybe I have been lucky or maybe Lou Tristao
>knew how to properly engineer a crank up...I support the latter.
>
>I use a crank up as I can work on my antennas from the roof. I also have
>the fold over mechanism if I ever want to move it again or restring it again.
>
>I have used telephone poles and Rohn 25/45 too but the Tristao has been my
>best investment in ham radio equipment!
>
>73, Dave K4JRB
Hi Dave,
"Safe" is a relative term. Yours is a very good story. Yours has obviously
been safe for you. It might well not have been safe if owned by someone
else not as careful as you are.
If you look at the "big picture" or as much of it as we can manage to see,
there seems to be a much larger number of tragic accidents involving
crankups than there are involving guyed, fixed towers, at least
percentage-wise. That is what I would base my opinion of "safe" vs "unsafe"
on and I'm afraid crankups fall into the "unsafe" area in my book. But,
like I said, "unsafe" is also a relative term and nobody likes to think
their installation is unsafe . . . even if it is.
There is a whole list of failures and accident modes that plague crankups
that just CAN'T happen on a fixed, guyed tower. I can't think of any right
off (other than simply falling from 100 feet) that can happen on a fixed
guyed tower that can't happen on a crankup. Can you?
Stan w7ni@teleport.com
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