[TowerTalk] Antenna Windload Ratings & Tower Windload ratings

[Kurt Andress]

The recent discussions here are all informative from those that actually 
know what is going on!
Everyone needs to understand this one principle:
The professionals that design towers are beholden to do that according 
to the most recent standard that clearly defines what they do, when they 
design a tower.
All of your antenna builders have absolutely no idea of what those 
standards are! Few, if any of them, have mechanical engineers capable of 
understanding those requirements....they are amateurs building what they 
think you will decide you will buy....that is marketing, not engineering!

I have studied and and documented this disconnect for over 30 
years......it absolutely drives me nuts!
The bottom line is that none of you can use any of the antenna 
manufacturers antenna area ratings with any of your towers, because they 
are not determined by the clearly defined standards that your tower 
designers use, because there is no real engineering expertise at any 
antenna manufacturer that is aware of what the Pro Tower designers do. 
And on top of that, few of the antenna suppliers and tower designers 
actually define the antenna area measurements their products 
service...... are they projected areas, or are they effective areas? 
These are all defined in the EIA/TIA 222 spec....I know what they are 
for each tower builder, because I have been into their detailed design 
analyses. They are usually citing antenna projected areas! What are your 
antenna builders citing? Rohn engineers are very clear about what they 
are citing!
I have lots  of analyses of commercially built amateur antennas, made 
from their own manuals, most all of them are simply WRONG, and not the 
least bit useful for deciding what can be put on a current 
professionally designed tower!
I have no interest in becoming involved with the usual TT pundit 
shitfights.
I just feel it is incumbent on me to come around about once every decade 
to remind everyone that this is still a huge unresolved problem, just 
like it was ~25 years ago, when I first looked into it....

73, Kurt, K7NV