For interest - in the UK, most of the towers are crank-up / tilt-over and
the standard ratings are published at 85 mph. As an example, my 18m
(heavy-duty) tower is rated to 11.5 sq ft at 85mph unguyed - I think the 24m
one comes in at about 7 sq ft unguyed and around 27sq ft guyed.
73,
Andy Cook, G4PIQ.
g4piq@blacksheep.org
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> >Since 70 mph is the minimum listed wind velocity for ANYWHERE in the US,
> >how
> >come crankup towers are always rated for 50 mph? I think I know why.
You
> >can't put any load on them at 70 mph, at least with any kind of safety
> >factor. I think we, as a group, should demand 70 mph ratings from
crankup
> >manufacturers. I know this will negatively impact their business . . .
as
> >it should!!
> >
> >Stan w7ni@teleport.com
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