My ladder makes the same noises when i'm driving down the road on cold days (transporting it)
it only does it when i am driving over 30mph, and the faster i go the louder it gets.
Just copy and paste the link into your browser address box and it should open. Then scroll down to the bridge video.
I just opened it on my phone, and I don't twitter.
Hope it works...
Len
“To invent, you need a good imagination and a big pile of junk.” (T. Edison)
"I must be on the way to success since I already have the junk". (Me)
It's a resonance issue.
The wind blowing through the cabling sets them to vibrate, and produce noise. It can also collapse a bridge if you setup the right resonance. https://www.youtube.com/watch?v=XggxeuFDaDU
Around here when we get strong winds blowing.
It will set up a vibration in the high tension electrical wires on the power poles.
Thus, you'll get a whooping, and or high pitch whine from them.
OK, thanks! My daughter bought a paddleboard from a shop near me, and after driving 20 miles, I couldn't take the "humming" from the tie ropes any longer! Had to yell to be heard in the car above the singing ropes. Later discovered things like garden hose sections over the ropes would stop the singing.
Some say Tesla almost brought down the Brooklyn Bridge with his "thumper" device attached to it.