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can anyone explain the regulations for antenna lights? that is, can you tell by how many white strobes how high the antenna is? just curious...
i don't plan on jumping any antenna's around here soon, but i'm curious if i can just tell driving by the height without an aerial map.
thanks

http://www.vertical-visions.com/14antenn.html

I asked the same question for the same reasons to someone a while back, they gave me that link.

thanks :)

Be careful with that chart. There has been some contention on Blinc that chart may be innacurate. Use your sectionals, tower markings, and rangefinders.

My understanding is that there is no actual regulations on colored light markings for antennas. A GENERAL guideline is a white light every 100' on bigger towers, and a red light every 300'.
The only REGULATIONS I know of would be the ones mandated by the FAA. Typically any tower with a light will be on a sectional. To be sure, get out your handy rangefinder and from a single spot relatively close to the antenna, shoot the base of the antenna, then the top of the antenna, and use basic trig to find the height. I'd recommend doing this method from at least three different spots to ensure accuracy.
The other surefire way of course is to climb it and count rungs...

Apart from FCC requirements, the marking and lighting of airspace obstructions is governed by 14 CFR Part 77. The marking and lighting requirements are published by the FAA in the form of advisory circulars (AC). AC 70/7460-1K is the current controlling document, and AC 150/5345 is the current lighting specification. A complete list of these and associated documents can be found at:

OBJECTS AFFECTING NAVIGABLE AIRSPACE

Particularly, AC 70/7460-1K is the document you seek.

Good luck staying awake whilst reading the above. After reading it, I think you'll find that the knowledge isn't that useful. Also, beware the use of Aviation Sectionals; I've noticed them to err on the side of conservatism. You should recall that these are used for warning pilots of obstructions, so a conservative error from that perspective is contrary to a conservative error from OUR perspective.

You might brush up on your right-angle trigonometry and get better results than using obstruction lighting specifications as your guide. You'll need a clinometer (and if you had a laser rangefinder that was retrofitted with a clinometer you'd have the best of possibilities) and some accurate strides, but it can be done. Check the middle of this page.

Have fun and be safe!

Gardner
base311
(edited to include direct link to ac 70/7460-1K)

This is by no means a good guideline. I don't know where you are jumping, or how you measure height, but had I followed your guidelines, I'd be dead by now.
Disclaimer: This is not a guideline. This is only from personal observation.
White lights are usually STROBE lights and are spaced farther apart than red lights. Red lights in my world are generally around 150 feet apart. If the tower has one red light, it is safe to assume it to be under 150 feet. Now, a tower with 2 red lights may be as short as 160 feet, although it can be up to 300 feet. If red lights were every 300 feet, I would be able to assume that this 2 light tower is 600 feet. Much different than jumping a 300 footer.
DO NOT rely on guidelines about towers. Only for estimating purposes. If it has more than two lights, it is most likely jumpable(I ran across a 3 lighter that was 300 feet). If it has two lights, take more measurements before jumping (should happen without being said).
DO NOT BELIEVE ANY INFORMATION you have not collected yourself. Which means you should not believe a single word of this post either.
Good. I hope you don't. You'd be more whacked in the head than me if you listened to CrazyThomas.
I still get in trouble listening to CrazyThomas.
Peace,
Thomas

Towers in our neck of the woods are pretty random.

Just some quick examples:
A 1000' guyed we just looked at 130 ft per red light.
2 2000' guyed: 300 ft per blinking white.
260 ft freestander: one blinking strobe at the top
280 ft freestander: 2 red lights about 140 ft apart.
250 ft freestander: one red at the top.
1500 ft guyed: 200 ft per blinking white.

So be careful. Best general rule is if its tall and has lots of lights (over 5) its high. But you should always plan your jump to the altitude you will be exiting from and the landing areas. Taking a range finder with you is an excellent idea!

Ummm... This doesn't sound correct.

Most of the big towers have white lights arranged at every 300'. However, there are exceptions such that you may see a light at 300', 700', and then 1000'. The towers with red lights frequently have lights placed at every 140' or 150'. Smaller towers follow different guidelines though.

Do not rely on any general rules. I've seen several towers that defied most light placement rules.

Here's the real deal...

ftp://ftp.synclogic.net/flashtech/pdf_files/charts/whitelight.pdf

ftp://ftp.synclogic.net/flashtech/pdf_files/charts/redlight.pdf

ftp://ftp.synclogic.net/flashtech/pdf_files/charts/duallight.pdf

Rember different rules in different places... I can see an chimney from the window,it have 3 redligths on.. BUT its max 150ft... im near an airport,and here the restricts talk about ligth on objects over 75ft.. BE AWARE

Which reminds me, I tested out my Sherpa on a tower with known platform heights recently. I zeroed it out at the base and compared at the platform levels. It was almost dead-on (+- 15 feet).

So you can gauge AGL in addition to windspeed. Very handy.