what are those balls that are on a wire hanging around a bridge to let airplanes know there is a bridge?

Answer 1

They're spherical plastic, hanging on a wire. They're in place to alert aircraft to the presence of the wire, which can be difficult to see from an aircraft performing an emergency landing.

Particularly at night, power and phone lines can be difficult to see or overlooked in an emergency situation.

Given that the night IFR practice for a single engine aircraft is to descend to 300' AGL before turning on the landing lights, and then turning them off if you don't like what you see, pilots need all the warning they can get about the placement of suspended wires.

I've seen them along interstates in areas that were flat as a fritter out in the Southwest, on a friend's ranch, over rivers, and more than a few gorges that would be tempting for a pilot to try flying through.

You have no idea how hard I tried not to make a joke on this one.

Fly the Friendly Skies!

Answer 2

Well...yes & no.....
The "balls" are placed along the length of "wires"
at odd intervals to prevent the wire from going into "harmonic "oscillation ,which is not good for the wires or the supporting structure
Certainly are a heads up to low flying pilots
Since the wires hang below the tops of towers & bridges , the
real warning devices are the red beacons at the top of the structures.
As mentioned, if you see them in level flight out your side window you are too low..
Best regards

Answer 3

If the bridge is going over a river, there may be a seaplane base on the river, so they put those there on any powerlines also crossing the river so pilots landing at the seaplane base will see the wires, not just the bridge.

Answer 4

These balls help the pilots of any low flying object (helicopters, light aircraft, fighters, etc, etc ) to identify the presence of these wires. As while flying it is very difficult to see these wires, as they merge with the background.

Answer 5

Those are there to identify the location of the wires, which are hard to see from a moving aircraft. As for what they're made of, I think plastic, or aluminum for the older ones.

Answer 6

You will see them anywhere there is higher than normal low flying aircraft. You will often see them on power lines that are near the ends of runways at small airports. You will also see them on lines that are very high, such as high power lines that cross a canyon or river with high banks. You will find them in areas with high helicopter traffic, especially around military bases. The purpose is obvious, let pilots know they are there.

Answer 7

Not for airplanes. For helicopters. Sometimes helicopters are needed for inspection purposes. They use thermal imaging to check for cracks or fatigued areas in the structure. The "balls" identify wires or other objects that might not be seen otherwise.

Answer 8

They belong to the last guy who flew too close to the bridge.

Answer 9

If you can look out of the windscreen and only notice a bridge when you see balls that are on a wire somebody is gonna get investigated by the FAA.............

Answer 10

they are so the air plane can see were there is wires that way they dont crash into the wires