Flying near antenna towers

[FoxhallGH]

You know some words and a tad bit of theory. Application in the real world is quite different. I’m not sure why you would list IF, it would drive their frequency even lower and away from 2.4ghz. Just stick to drones.

All of those words are real words, and that's not 'theory' it's proven RF fact! ... There are some antenna types & frequencies that will blow a Drone away and that shouldn't be ignored. There are practical examples where people have flown drones and seen effects, and some who have had no effects - but that doesn't mean that the laws of physics go on holiday when you fly your drone ... If you value your Mavic, don't fly it in front of directed RF energy!

 

[LowCountryFlyer]

I've done a cell tower inspection with a Phantom IV. Be careful with that stuff as the strength of the EM fields eminated from those and other utility devices eg high tension towers, microwave transmitters, etc. are quite strong. A proper preflight briefing with the tower operator to review both the transmission frequencies and power output prior to flight is a must. In addition if this is an activity for earning a living, consider using an enterprise aircraft with has a specifically EM hardened design such as a Matrice or similar for this kind of work. Mavics are really just intended to be high end flying cameras for shooting pretty footage while on vacation and not for use in these kinds of inspections or work.

 

[tbgelig]

Whoever he is, he clearly has no idea about electronics or radio theory. Final transmission frequency is a tiny tiny part of the calculation. He seems to think harmonics don't exist, intermediate frequencies dont exist, internal timers and local oscillators dont exist in the circuits, induction effects dont exist, RF "quietening" from being swamped by a huge signal doesn't exist.
In addition to being completely wrong about that subject matter he's also completely wrong about mast frequencies - a large number will use 2GHz area for a mobile band and in addition most masts have microwave beams to adjacent masts that can be in 5GHz or harmonics thereof as well.
...and thats assuming its a cell phone mast. There could be any number of different spectrum users on a mast or sharing a mast.

A "big drone guy" is probably the last person i'd listen to when he's talking about something he has no qualifications in such as RF theory.

so what is the answer to the question? Is that a No? Considering the RF power inverse square law?

 

[ExUmbra.Solutions]

I will start this by saying that flying around towers can be a bit of a gray area on many levels. Some states may define this as critical infrastructure but this is a loose definition at best and to the best of my knowledge has never been prosecuted. The greater issue is actually that while I am aware of the airspace being free to all from grass to space the tower is owned by a towerco and the equipment is owned by a telco, or a variety of them making this private property.

It is because you are in proximity (the distance isn't defined) to the tower and equipment that you have to have permission from the equipment or tower owner, with a recognized purpose or you could be considered trespassing. It's also why they can make me carry a $5M/$5M insurance policy when I fly drones around them every day. All that being said I can't say whether you are going to be ALLOWED to fly drones around towers but they are more than capable of it.

I have a decent-sized drone company and have flown hundreds of radio and TV broadcast towers and am scheduled to fly somewhere around 15,000 telco towers across three different efforts for this year. I and my pilots have flown nearly every type of RF broadcasting structure around.

Speaking first of telco towers... The biggest issue is going to be a temporary loss of GPS signal. This issue is usually so fleeting that the signal loss isn't even long enough to trip the drones warning about it. It is a bigger issue with RTK loss but that's not going to be an issue at concern here from the sound of it. I have never had a control loss issue across a wide spectrum of drones due to RF or physical structure interference. I typically fly my missions at 24-30 foot radius orbits or vertical "slices" at the same distance from tower center. We have taken the drones in as close as 6 feet when required and again, no issue. This includes hovering for extended periods directly in front of a MW antenna.

Radio and TV broadcast towers are a little different. They are putting out orders of magnitude more power but typically the frequency is so far removed from the drone's that it's a nonissue. We have the station owner "turn down" when using our RF sampling equipment but that is to protect the equipment and measurement antennas, not the drone. In late 2023 I flew a coolant leak detection mission while broadcasting at full power to demand the coolent flow on a 1500-foot antenna and was 15-20 feet off the structure while it pushed all the power it had and had zero issues with my aircraft.

And if you want to get paid to fly around towers... I am always hiring good pilots.

 

[ExUmbra.Solutions]

So, when you fly these towers, is permission needed or just don't land on the property?

as drone pilots we all know that airspace is federal and Henry you can fly where you want so long as you don’t make contact with private property or restricted or controlled airspace. In reality it’s a but less clear cut. I fly towers nearly everyday and the tower and the equipment on it are all owned by separate entities and considered private property and they will tell you that you are trespassing if you fly in proximity to them. All that being said I have never heard of it being enforced and have never actually had an issue. But they are strict enough in it that I have to carry a hefty insurance policy to fly these missions even after we conducted field testing to the show that no small drone could damage anything on the tower.

 

[ExUmbra.Solutions]

Is the height of cell towers basically all the same......
I wonder what that height is?

In the last four days in northern CA I flew inspections and modeling for a set of equipment that was mounted on 12 foot poles instead of a tower, a self support tower over 350 feet tall, a guyed tower approaching 600 feet tall, and a handful of monopoles and monopoles that were 50-100 feet tall. Tower height is usually just decided during the build phase depending on what the owner wants to sell coverage and soace for and can get permitted for.

 

[mobilehomer]

The fact is this: you will be perfectly fine as long as it's not broadcasting Taylor Swift.

 

[Dbez1]

I have no technical knowledge to add here but I seem to remember we’re supposed to stay 2,000’ from guy wires (which always seemed overkill to me). I’m thinking those with an FAA waiver doing tower inspections are exempt from this.

 

[ExUmbra.Solutions]

I have no technical knowledge to add here but I seem to remember we’re supposed to stay 2,000’ from guy wires (which always seemed overkill to me). I’m thinking those with an FAA waiver doing tower inspections are exempt from this.

I’ve heard this before and I am not sure where it comes from except to say unmanned or traditional planes and helicopters all want to error on the side of caution for guyed towers and guy wires. One interesting point of fact that we have validated with the FAA and insurance companies both is that the guy wires serve as the footprint of the structure so when we are measuring our altitude relative to a structure we can use the entire footprint of that tower space which gives us a lot more altitude further out for things like RF data gathering. Their thought is that so long as we are in the overall guyed footprint of the tower we have no fixed or rotary wing collision concerns and our allowable altitudes are relative to the tower.

 

[BigAl07]

I will start this by saying that flying around towers can be a bit of a gray area on many levels. Some states may define this as critical infrastructure but this is a loose definition at best and to the best of my knowledge has never been prosecuted. ....

With all due respect, only the FAA can "designate" Critical Infrastructure. Any entity can "submit the request for consideration" and often times that is granted but it's important to distinguish that only the FAA can define/designate a Critical Infrastructure. Any entity submitting has to meet a very specific set of criteria to be designated as Critical Infrastructure. Even the Army Corp of Engineers has to submit and get approval for their many facilitates (which are not automatically Critical Infrastructure but many believe and have said they are) and they don't always get approved. You might be surprised how few there really are right now (this will change as the tech evolves and more fears come to the front).

If you have an area you think is Critical Infrastructure or you just want to look around here is a method you can potentially see these areas. It's not easy but if it's really an issue you can dig into this and see them but there's no real "details" for obvious reason:

FAA UAS Data Delivery Service

Federal Aviation Administration - UAS Open Data Site

udds-faa.opendata.arcgis.com