I haven’t traversed one of those dangling rope bridges 500 feet up and spanning a crevice in the Himalyas, but I have driven across the Eggemoggin Reach - Deer Isle (suspension) Bridge in Maine. In fact, I did last week when it’s two narrow lanes were down to one. The ride was white knuckle all the way. Those cable stays you see? They’re about 1/2-3/4 and while there’s a lot of them, it’s still a bouncy ride. As I drove down to the bridge’s southern approach, I had to pull over and process its steepness, height and narrow width. I did not know then that it was "a sister" to The First Tacoma Narrows whose famous collapse in 1940 from a condition known as "mechancial resonance" was caught on video. I’m glad of that. Of course, bridge integrity following the I-35W bridge collapse in Minneapolis is on a lot of minds.
I forged ahead only to be stopped at the top of the 1,088 long bridge for oncoming traffic. My palms sweated as a string of cars passed by. The bridge bounced moderately 98.7 feet about the famous Eggemoggin sailing channel. As the last car passed, all done, I thought. Time to move. Wrong! A lone and huge tractor trailer approach at slow speed, it’s driver’s hands welded to the steering wheel like Vice-Grips. The bridge’s bounce now seemed more like a wave or ripple through the roadway deck (The First Tacoma Narrows Bridge was nicknamed "Galloping Gertie"). That truck passed as did 90 seconds or so and it was time for second truck. Then we are allowed to pass and were quickly back on terra firma. It didn’t take long to realize only essentially one truck creeping along at 5 MPH was allowed on the bridge at one time.
Designed by David & Steinman (famous bridge architect David B. Steinman helped design Galloping Gertie), The Deer Isle Bridge was built in 1939 for much lighter less powerful vehicles and was undergoing major re-decking the day we crossed. That’s why it was down to one lane. On the way back to the northern approach, we were held on land waiting for oncoming traffic. Whew!