Who's got the biggest...

[jshawley]

Oh, and I forgot about the 650' TV tower that's ON THE AIRPORT PROPERTY at Springfield Downtown (3DW) and the three or four other 350' (+/-) towers that are in the traffic pattern.

That airport can be quite interesting for someone who is not familiar.

In my illustrious career of 297+ hours, I've never flown into 3DW. Someday I will, just to say I have. BTW, there is a really good video history of that airfield that can be found on Ozarks Public TV.

 

[timwinters]

2000' sure seems to be the magic height limitation (though some seem to have cheated a touch by setting the tower in a concrete base or some such)

What is the limit on guyed towers? (what is the physical entity that prevents taller?)
Seems like the highest is 2000' but function may be what is topping them out there.

Well, I got curious enough to check into it. From an FCC website:

Although there is no absolute height limit for antenna towers, both agencies have established a rebuttable presumption against structures over 2,000 feet above ground level. The FCC has a policy that applications filed with the FCC for antenna towers higher than 2,000 feet above ground will be presumed to be inconsistent with the public interest and the applicant will have a burden of overcoming that strong presumption. The applicant must accompany its application with a detailed showing directed to meeting this burden. Only in the exceptional case, where the Commission concludes that a clear and compelling showing has been made that there are public interest reasons requiring a tower higher than 2,000 feet above ground, and after the parties have complied with applicable FAA procedures, and full Commission coordination with FAA on the question of menace to air navigation, will a grant be made. See 47 CFR § 1.61 Note.

The FAA presumption against construction of structures over a certain height is set forth in the FAA rules. A proposed structure or an alteration to an existing structure that exceeds 2,000 feet in height above the ground will be presumed to be a hazard to air navigation and to result in an inefficient utilization of airspace and the applicant has the burden of overcoming that presumption. Each notice submitted under the FAA rules proposing a structure in excess of 2,000 feet above ground must contain a detailed showing, directed to meeting this burden. Only in exceptional cases, where the FAA concludes that a clear and compelling showing has been made that it would not result in an inefficient utilization of the airspace and would not result in a hazard to air navigation, will a determination of no hazard be issued. See 14 CFR § 77.17(c).

 

[Kelvin]

Possibly the Voice of America antenna farm...
35°43'20"N 77°8'40"W

I flew past a bunch of tall towers in North Carolina one time. Someone told me they were US Navy sub-communication towers. They were very tall. Anyone know how tall? West of Kill Devil Hill, as I remember.

Dan

 

[denverpilot]

Well, I got curious enough to check into it. From an FCC website:

Yeah, that's the gist of the text on the Wikipedia article I posted. But I think the engineering-heads are curious if there are some significant physical limitations above 2000' that also make the structures themselves impractical.

 

[Steve]

don't forget the

http://www.af.mil/information/factsheets/factsheet.asp?id=3507

"These aerostats can rise up to 15,000 feet mean sea level, while tethered by a single nylon and polyethylene constructed cable. The normal operating altitude varies by site, but the norm is approximately 12,000 feet MSL."

 

[COFlyBoy]

don't forget the

http://www.af.mil/information/factsheets/factsheet.asp?id=3507

"These aerostats can rise up to 15,000 feet mean sea level, while tethered by a single nylon and polyethylene constructed cable. The normal operating altitude varies by site, but the norm is approximately 12,000 feet MSL."

Yeah, I filtered the balloons out of the obstacle file that I got from the FAA digital products website.

I read a detailed report about a Cessna that ran into one of the cables for a balloon in Florida. It sheared the wingtip off. The cable held though.