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Need Windload Figure for Nanobridge M5

AT&T is mapping the tower and needs the windload (no ice). Ubiquiti's home page gives me the weight, but not the windload.

Structural studies need windload. Where does Ubiquiti "hide" this information. I say hide because I have looked hard for it.
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Re: Need Windload Figure for Nanobridge M5

It's not hidden; it's never been published. Dave

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Re: Need Windload Figure for Nanobridge M5

I really wish that they would publish the figures. I'm about to sign a roof top lease and really could use those figures in engineering our mounts. Plus it would make the land lord much happier.
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could do it yourself

for more detailed formulas (real world for elevated antennas) try this site...

www.arraysolutions.com/Products/windloads.htm



The Generic Formula

For using the actual sustained wind speed expected (were we to actually determine it) :

Force, F = A x P x Cd

A = The projected area of the item

P , Wind pressure (Psf), = .00256 x V^2 (V= wind speed in Mph)

Cd , Drag coefficient, = 2.0 for flat plates. For a long cylinder (like most antenna tubes), Cd = 1.2.
Note the relationship between them is 1.2/2 = .6, not quite 2/3.
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Re: Need Windload Figure for Nanobridge M5

Gene has one, forum.ubnt.com/showthread.php?t=55371
And I can't find mine.
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send UBNT-Matt 8 miles from work

maybe Matt could load up a bunch of radios in his car and drive 7.9 miles from work to put them in the NASA Ames Research Center wind tunnel. Heck I'll pay for his gas if he pays for the testing.
Clear Line of Sight and Freznel Zone isn’t everything; It’s the only thing.
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220px-The_80_by_120_foot_wind_tunnel_At_NASA_Ames (1).JPG
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Re: Need Windload Figure for Nanobridge M5

If NASA is too busy, he could also try Auburn or any other college that is close to him that offers engineering courses. Mississippi State has one killer wind tunnel for their aerospace courses, but that would be a long drive for him. Icon Biggrin
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Re: Need Windload Figure for Nanobridge M5

Cool idea, but very few people actually test in wind tunnels any more. It's all done mathematically or using fluid dynamic modeling and FEA.
For the NS's treat them as a plain rectangle and do the math - here's a very good white paper from Andrew on the subject
docs.commscope.com/Public/wind_loading_on_base_stationantennas_white_Paper.pdf
Jim
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Re: Need Windload Figure for Nanobridge M5

Found it, will upload it later tonight.
WHT = Short Form Acronym for "You couldn't handle me even if I came with instructions!"
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Re: Need Windload Figure for Nanobridge M5

And yet, there are no further responses on this thread.
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Re: Need Windload Figure for Nanobridge M5

This is a 6 year old topic, please don't necro bump.

Wind loading figures should be available in the data sheets. If this spec is missing from a product sheet, please let us know.

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Re: Need Windload Figure for Nanobridge M5

[ Edited ]

The windload figures specified in the datasheets are in incorrect units. Windload should be listed in square feet or square meters equivalent flat plate load. In other words, 1.1 sq ft or 0.9 square meters. It does not mean 234 kg at 160 kph. Certainly, maximum survivable wind is useful. Being able to survive a 160 kph wind doesn't matter if the size-equivalent area of the antenna causes the tower to fall over in 50 kph winds.