400' AGL

[Sitka78]

I have a hill close to my home and would like to go up to the top of it. The height is 982' above sea level. I understand that if we stay within 400' of the surface, we can continue to fly up and stay close to the hill. Is this an allowable thing to do? I also understand that I could go an additional 400' above the top of the hill and still remain legal. Sure would like to know if I am on the right track. Maybe this only applies to a structure such as a tower or the like. The altitude where I live is 80'.

 

[msinger]

In the US? It would be perfectly legal for a hobbyist as long as there is no more than 400 feet between the bottom of the drone and the ground below it. That's the definition of 400 feet AGL.

 

[kadras]

I have a hill close to my home and would like to go up to the top of it. The height is 982' above sea level. I understand that if we stay within 400' of the surface, we can continue to fly up and stay close to the hill. Is this an allowable thing to do? I also understand that I could go an additional 400' above the top of the hill and still remain legal. Sure would like to know if I am on the right track. Maybe this only applies to a structure such as a tower or the like. The altitude where I live is 80'.

You can fly no higher than 400' above the surface directly below the aircraft, so yes, you could fly to the top of the hill as long as you remain with 400' of the surface. You don't get an extra 400' bonus at the top. If there is a structure there, and you have a Part 107 cert, then you could fly up to 400' above the top of the structure.

 

[boldblue737]

You can fly no higher than 400' above the surface directly below the aircraft, so yes, you could fly to the top of the hill as long as you remain with 400' of the surface. You don't get an extra 400' bonus at the top. If there is a structure there, and you have a Part 107 cert, then you could fly up to 400' above the top of the structure.

you aren't wrong but i think he views the 400 feet above the highest point of the hill (which is LEGAL) as a "bonus" because he will be standing at the base of the hill and the drone will be much higher than 400' above where he will be standing controlling the drone. all legal.

 

[kadras]

Of course, all of the above is legal as long as you're within the altitude requirements of the airspace you're in.

 

[THE CYBORG]

 

[msinger]

because he will be standing at the base of the hill and the drone will be much higher than 400' above where he will be standing controlling the drone. all legal.

It doesn't matter where you are standing (in the US). You just need to keep it below 400 feet AGL.

 

[Starz]

View attachment 77383

I like this one. Pretty simple to understand.
Interesting how “AGL” can have so many hidden meanings when in reality there is only one.

 

[rfc]

View attachment 77383

Not to nit pick, but all the "400 ft" arrows should be vertical.

 

[sar104]

Not to nit pick, but all the "400 ft" arrows should be vertical.

In the US you are quite correct. The graphic above is a CAA (UK) guide, where they explicitly went with the nearest point, rather than the ground directly under the aircraft.

 

[AMann]

View attachment 77383

I believe there’s an error in this illustration, the diagonal arrow should be straight down 400 feet. The way it is angled, the drone will actually be higher than 400 feet in that location which would actually be right in front of the pilot if you draw a line straight down from where the drone is.

 

[AMann]

Not to nit pick, but all the "400 ft" arrows should be vertical.

Not to nit pick, but all the "400 ft" arrows should be vertical.

You beat me to it, but I explained why.

 

[AMann]

I have a hill close to my home and would like to go up to the top of it. The height is 982' above sea level. I understand that if we stay within 400' of the surface, we can continue to fly up and stay close to the hill. Is this an allowable thing to do? I also understand that I could go an additional 400' above the top of the hill and still remain legal. Sure would like to know if I am on the right track. Maybe this only applies to a structure such as a tower or the like. The altitude where I live is 80'.

I’m not sure how air traffic is in your area, but we often have planes flying low over our local hills in order to get to a nearby airport and air tanker base, thus so I would never fly 400 feet above ridges or any hills while standing at the base of it if I cannot see what is coming over and past it from the other side. This is a good rule of thumb as well for buildings because you just can’t see if I helicopter or some other aircraft is approaching the building opposite of where you are standing.

 

[sar104]

I believe there’s an error in this illustration, the diagonal arrow should be straight down 400 feet. The way it is angled, the drone will actually be higher than 400 feet in that location which would actually be right in front of the pilot if you draw a line straight down from where the drone is.

And the reason is in post #10.

 

[pjarvo18]

Keep in mind you will have to set your maximum height to well above 120m/400ft If you want to start at the bottom of this hill and fly up it. Your maximum height will be determined by your takeoff point and not the ground below it. That or you will have to land part of the way up and take off again to achieve the overall height you are looking for.

 

[Simmo]

Think of a 400ft piece of string hanging below your drone. (putting all other physics aside) the string should always touch the ground... legally!

 

[Rockycat]

View attachment 77383

Puts that question to rest. A picture is worth a thousand words.

 

[THE CYBORG]

I agree but hey I only copied & pasted.
Alteration now made

 

[Sprocket]

I agree but hey I only copied & pasted.
Alteration now made



View attachment 77404

Let's say he takes off from the top of the hill and heads to the right in this illustration. How does he determine his exact height while flying over the "valley"?

 

[Starz]

Let's say he takes off from the top of the hill and heads to the right in this illustration. How does he determine his exact height while flying over the "valley"?

The key to all of this is the term”AGL”
If that is not something that can be understood by the person with the rc in their hand, they should remove it from their hands and find a different hobby.