The campfire sounds like a good deal.
The rest I'm less sure of, though.
I thoguht I mentioned that this tower is in the Sonoran desert of
Arizona, not Florida. So, I don't have to plan for hurricanes, at
least.
I won't be "up north" either, when operating remote. But, I will be
far enough away from the site that I can't count on getting to it in
under an hour. May as well be in New York anyway, then, right?
Larry Wo0Z
On Mon, Jun 25, 2012 at 1:49 PM, David Jordan <wa3gin@comcast.net> wrote:
> HI Larry,
>
>
>
> It's a good idea to go find the local radio club and get acquainted with
> some of the 'old timers'. Time to listen to their camp fire stories about
> ham antennas, towers, etc.
>
>
>
> >From the US Tower manufacturer WEB Site for ham crank-up towers:
>
>
>
> Windloading ratings based upon IBC 2006 (TIA/EIA-222-F) at 76mph and 90mph
> 3-second gusts:
>
> HDX-538: 26.6 sq. ft.
>
> HDX-555: 23.4 sq. ft.
>
> HDX-572: 14.1 sq. ft.
>
> HDX-589: 9.2 sq. ft.
>
> HDX-5106: 1.0 sq. ft. at 90mph
>
>
>
> So, the height you leave the antenna cranked up when you spend your summer
> up north is really determined by a couple of things:
>
>
>
> - Are you BRAIN DEAD? If so, then leave it cranked up to 72ft *
>
> - Are you DIM? If so, then leave it cranked up to 62ft *
>
> - Are you a RISK TAKER? If so, then leave it cranked up to 52ft *
>
>
>
> Are you aware of the following information (below)?
>
>
>
> More storms hit Florida than any other US state. Looking at the years from
> 1851 to 2004, for hurricanes of Category 3 and higher: Florida had 35
> hurricanes; Texas, 19; Georgia, 3; Alabama, 6. (From the National Hurricane
> Center).
>
>
>
> Typically, at least one named storm makes landfall in Florida every season.
>
> Some areas of Florida may be as risky as the Caribbean islands. The chances
> of Miami being hit by a hurricane is "higher than anywhere in the Caribbean"
> (--see article at About.com's Caribbean Travel website.) The period from
> August to October is the height of the hurricane season in Florida.
> Remember, though, that Mother Nature isn't reading any calendars.
>
>
>
> For Floridians, hurricane preparedness is part of life. For example, read
> the Hurricane Survival Guide at the Orlando Sentinel newspaper site.
>
> Some Years are Worse than Others
>
>
>
> 2004, for instance, was a big year for Florida hurricanes: Charley, Frances,
> Ivan and Jeanne hit the Florida coast, causing over 20 deaths plus more than
> $40 billion in damage. 2007, meanwhile, saw three tornadoes sweep across
> central Florida with several fatalities.
>
>
>
> * Category One Hurricane:
> Sustained winds 74-95 mph (64-82 kt or 119-153 km/hr). Damaging winds are
> expected. Some damage to building structures could occur, primarily to
> unanchored structures (such as school portables). Some damage is likely to
> poorly constructed signs. Loose outdoor items will become projectiles,
> causing additional damage. Persons struck by windborne debris risk injury
> and possible death. Numerous large branches of healthy trees will snap. Some
> trees will be uprooted, especially where the ground is saturated. Many areas
> will experience power outages with some downed power poles.
> <http://weather.gov/cphc/summaries/1982.php#Iwa> Hurricane Iwa (passing just
> northwest of Kauai in 1982) and
> <http://weather.gov/cphc/summaries/1959.php#Dot> Hurricane Dot (landfall on
> Kauai in 1959) are examples of Category One hurricanes that directly
> impacted Hawaii.
>
> * Category Two Hurricane:
> Sustained winds 96-110 mph (83-95 kt or 154-177 km/hr). Very strong winds
> will produce widespread damage. Some roofing material, door, and window
> damage of buildings will occur. Considerable damage to unanchored structures
> and poorly constructed signs is likely. A number of glass windows in high
> rise buildings will be dislodged and become airborne. Loose outdoor items
> will become projectiles, causing additional damage. Persons struck by
> windborne debris risk injury and possible death. Numerous large branches
> will break. Many trees will be uprooted or snapped. Extensive damage to
> power lines and poles will likely result in widespread power outages that
> could last a few to several days. There is no record of a Category Two
> hurricane directly impacting Hawaii. Elsewhere in the United States,
> <http://www.nhc.noaa.gov/1995erin.html> Hurricane Erin (1995, 100 mph at
> landfall in northwest Florida) and
> <http://www.nhc.noaa.gov/2003isabel.shtml> Hurricane Isabel (2003, 105 mph
> at landfall in North Carolina) are examples of Category Two hurricanes at
> landfall.
>
> * Category Three Hurricane:
> Sustained winds 111-129 mph (96-112 kt or 178-208 km/hr). Dangerous winds
> will cause extensive damage. Some structural damage to houses and buildings
> will occur with a minor amount of wall failures. Unanchored structures and
> poorly constructed signs are destroyed. Many windows in high rise buildings
> will be dislodged and become airborne. Persons struck by windborne debris
> risk injury and possible death. Many trees will be snapped or uprooted and
> block numerous roads. Near total power loss is expected with outages that
> could last from several days to weeks. There is no record of a Category
> Three hurricane directly impacting Hawaii. Elsewhere in the United States,
> <http://www.nhc.noaa.gov/pdf/TCR-AL182005_Rita.pdf> Hurricane Rita (pdf)
> (2005, 115 mph landfall in east Texas/Louisiana) and
> <http://www.nhc.noaa.gov/2004jeanne.shtml> Hurricane Jeanne (2004, 120 mph
> landfall in southeast Florida) are examples of Category Three hurricanes at
> landfall.
>
> * Category Four Hurricane:
> Sustained winds 130-156 mph (113-136 kt or 209-251 km/hr). Extremely
> dangerous winds causing devastating damage are expected. Some wall failures
> with some complete roof structure failures on houses will occur. All signs
> are blown down. Complete destruction of unanchored structures. Extensive
> damage to doors and windows is likely. Numerous windows in high rise
> buildings will be dislodged and become airborne. Windborne debris will cause
> extensive damage and persons struck by the wind-blown debris will be injured
> or killed. Most trees will be snapped or uprooted. Fallen trees could cut
> off residential areas for days to weeks. Electricity will be unavailable for
> weeks after the hurricane passes.
> <http://weather.gov/cphc/summaries/1992.php#iniki> Hurricane Iniki, which
> made landfall on Kauai in 1992, is an example of a Category Four hurricane
> at landfall in Hawaii.
>
> * Category Five Hurricane:
> Sustained winds greater than 157 mph (137 kt or 252 km/hr). Catastrophic
> damage is expected. Complete roof failure on many residences and industrial
> buildings will occur. Some complete building failures with small buildings
> blown over or away are likely. All signs blown down. Complete destruction of
> unanchored structures. Severe and extensive window and door damage will
> occur. Nearly all windows in high rise buildings will be dislodged and
> become airborne. Severe injury or death is likely for persons struck by
> wind-blown debris. Nearly all trees will be snapped or uprooted and power
> poles downed. Fallen trees and power poles will isolate residential areas.
> Power outages will last for weeks to possibly months. There is no record of
> a Category Five hurricane directly impacting Hawaii. Elsewhere in the
> United States, <http://www.nhc.noaa.gov/pdf/TCR-1969Camille.pdf> Hurricane
> Camille (pdf) (1969, 190 mph at landfall in Mississippi) and
> <http://www.nhc.noaa.gov/1992andrew.html> Hurricane Andrew (1992, 165 mph at
> landfall in Southeast Florida) are examples of Category Five hurricanes at
> landfall
>
>
>
> UR kidding right? Dude you live on the west coast of FL. Hurrican
> land...if you aren't there and you want a tower when you return you better
> leave it cranked down all the way. The lowest of the hurricane categories,
> the type one, puts your tower at risk if cranked up. even a tropical storm
> would place it at risk.
>
>
>
> Leave it cranked down is my best advice or start putting your lunch money
> change in a bucket so you can replace the tower when it bends over.
>
>
>
> Good Luck and Have Fun Operating via the Internet,
>
> Dave
>
> Wa3gin
>
> Internet Remote since 2000
>
>
>
> * * seems like the wind load is not relevant question; at any height
> above40ft the risk of tower failure increase dramatically during an average
> tropical storm or hurricane (IMHO). Now find an antenna that will survive
> 90mph or greater gust ;-)
>
> *
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Larry Loen
> Sent: Monday, June 25, 2012 3:48 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Windload Planning for Towers
>
>
>
> What wind load should I actually plan for?
>
>
>
> Officially, it seems like the world is migrating to a 90 MPH
>
> (momentary) standard. That leaves me at 11 square feet in my
>
> location. But, the advertizing (at more like 50 MPH) suggests I can
>
> go up to 30 square feet without fuss with my HDX 572. Of course, they
>
> are taking no risks in stating something like that.
>
>
>
> Keep in mind that this is probably the only time in my life I'll have
>
> the money to put up a tower like this. So, I'm not interested in a
>
> design point that says I wasn't aggressive enough if it doesn't blow
>
> down someday.
>
>
>
> I want this thing to be standing 30 years from now, but I don't want
>
> to have the thing at 25 feet all its life either.
>
>
>
> I will eventually be operating remotely, so what I need to do in my
>
> case is plan to erect the thing and largely leave it there at whatever
>
> height (and antenna array) I deploy. So, I need to plan on 64 to 72
>
> feet of height here, depending on some of my choices.
>
>
>
> What do people on this reflector actually plan for and why?
>
>
>
>
>
> Larry Wo0Z
>
> _______________________________________________
>
>
>
>
>
>
>
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>
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>
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>
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>
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>
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>
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