I know that a telescoping flagpole has been suggested as an anemometer mast in the past, but has anyone actually used one and what are your opinions? This would be for a VP2 anemometer and not the larger, heavier Vue.
I have a very solid gable mount from my old Digitar days, but due to some spinal problems and landscaping vegetation below it, I probably can't place my 22' A1 ladder to install an anemometer up there without injuring myself. I guess I could hire out someone to do it or bother a neighbor for help, but often times these installations aren't one-shot deals. Sometimes they need to be serviced after a failure.
So I've been investigating the possibility of using a telescoping aluminum flagpole as a 20-ft anemometer mast. My concerns are how much sway might be expected in winds up to 80 mph, how much vibration in those winds can be expected from play in the telescoping segment joints, and would all this affect the wind measurements. I've looked at video demonstrations of various flagpole's operation with flags on them, but it doesn't seem that they were emphasizing their rigidity in the videos.
Also some poles have a twist and lock mechanism which seems that it would twist the alignment of the anemometer off of north as the pole is raised. I think the alignment could be twisted back to north by rotating the pole base, but on some poles there is no locking mechanism in the ground sleeve. This might allow the pole to twist due to wind torque on the anemometer arm.
So I've considered the following for telescoping flagpoles:
- Relatively easy installation compared to my gable mount
- Easy to collapse mast for anemometer servicing
- 20' will be higher than the mast I once had on my gable mount (17')
- Avoidance of roof top wind turbulence
- My limited placement options to avoid blocking my weather cam view or to minimize wind obstructions from trees and other houses
- Possibility of sway/vibration affecting measurements
Various flagpole dealers are claiming their aluminum poles are stronger than equivalent steel gauges and that their poles can hand 80-90 mph winds with 3x5 flags attached. This dealer seems to have the best price for what is offered, longest warranty, strongest aluminum, and the thickest pipe gauge of any I've seen: http://tele-pole.com/superior.html
If I buy a pole and it doesn't work out for an anemometer mast, I guess could always move it to the front yard to be a flagpole.