What are those orange balls on power lines, and what do they do?

2021-04-16 3:17 am
Mostly on old power lines in old neighborhoods, there are what seem to be fiberglass balls about 2 feet in diameter that have the power line running right through the middle of them.  (I can see the shiny fiberglass weathering out of the old ones.) 
  I thought that they might be insulators to keep different phase power lines from clashing and shorting out in high winds.  I used to think that they were warnings to low flying aircraft, but some of them are so low that they would have to be real barn stormers, rather I think those might warn house-movers.  My dad even joked that they were helium floats that helped hold up long runs of power lines.  Lastly, I just kind of guessed that they might be a physical impediment to rats running from building to building. 
  I couldn't find one of my old photos of them quickly so I drew this picture in paint:
更新1:

 Okay since I can't attach a picture or comment, here if you GOTO 29.802881445882463, -95.40362637042956 coordinates in google street views, and look up at the power lines above the stoplight, you'll see the two balls in question, also about two blocks away you'll see a hospital that has a very active life-flight helicopter...DUH! I've always been picturing biplane cropdusters!  Not airport, helipad.  Good link skeptik.

更新2:

Okay, so here's the real kicker anonymous, that instead of being near an airfield, out in the open anywhere, or near a busy heliport, they were on a powerline strung between two buildings in a residential street about thirty-five feet above the yellow stripe.  To become relevant you'd have to fly down 19th street between the Venus hair salon and some antique shops.  Look out for that low hanging stoplight!

回答 (5)

2021-04-16 8:20 pm
They are merely to allow low flying aircraft to see them and nothing else.

The FAA requires them
2021-04-16 3:26 am
They are for visibility.

Their sizes and spacing are laid out by the FAA.  Even the ones fairly close to the ground.  Because planes get all the way down to the ground when landing.

---
Incidentally - regarding your update:
You should be able to attach a photo.  But you have to save it to your hard drive first, then copy it from there.  You just can't do it direct from Street View.

Like this:
2021-04-16 3:21 am
Provides visibility to any low-flying aircraft.
Balls can also provide some tension stabilization in certain places.
2021-04-17 2:57 am
So you're smart enough to get on YA and write in complete sentences, but you're not smart enough to know what most 5th graders know?
2021-04-16 2:40 pm
To prevent the wind from making them whip, to and fro. A hospital has them to mark a helicopter landing pad. One black ball means onloading ammo.


收錄日期: 2021-04-24 08:45:19
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20210415191728AA6pdHZ

檢視 Wayback Machine 備份