Question about the 400 ft. rule

[zocalo]

I don't know, but that sounds like a great idea. Everything is better with a bit of calculus and rocket science added.

Don't forget the brain surgery for when your head explodes trying to work it all out.

 

[Meta4]

I see videos of drones flying over the edge of cliffs for astounding footage, however it would seem that they are immediately in violation if the drop is more than 400 feet.

You have to apply a little common sense.
If you were to fly 10 metres out over the edge of a 500 metre sheer cliff, you would be 500 metres above ground level, and upset fundamentalist forum rule people.
But the whole intent of the rules is to maintain aviation safety.
You aren't going to encounter any other aircraft flying close to a cliff edge.
The rules as written are brief and don't allow for every complicated scenario.
The number one rule is don't fly in a way that endangers others.

 

[droneworx]

How can such a simple and plain rule get so convoluted in such a short time and turned into Rocket Science with Calculus requied to solve it.

because, like most government rules and regulations, they are open to interpretation, and are generally unclear in relation to covering all different aspects like "what happens if im at 200 feet and fly off a cliff and am suddenly now 600 feet up?"

 

[old man mavic]

i would like to know how any of us flying our UAVs around the skies apart from the point directly above us can really say we are only at the legal maximum at any given moment other than hoping we are ok more to the point is how anyone else on the ground is going to be able to say at what height above the ground we were without some very sophisticated radar range finder. i personally never go much above 200ft theres no point if you are taking pictures because the image is to small to be of interest i am just going to carry on flying the same as i have always done following the guidelines laid down by the CAA

 

[bushie]

Sometimes it is avant aagous living in a country thst is essentially flat

 

[Meta4]

i would like to know how any of us flying our UAVs around the skies apart from the point directly above us can really say we are only at the legal maximum at any given moment other than hoping we are ok more to the point is how anyone else on the ground is going to be able to say at what height above the ground we were without some very sophisticated radar range finder.

Again common sense has to be used.
You are never going to find an inspector with a very tall ladder and a 400 ft tape measure.
No-one is ever going to know if you are 400 ft +/- 10 ft, and no-one really cares except forum fundamentalists.

When you see a Cessna flying past, its pilot (almost certainly) can't tell how high he is above the ground level either and he's doing what you have to.
He's making an intelligent estimate based on what information he has, plus experience.

 

[JDawg]

I'm wondering if following the terrain at less than 400 feet is in compliance with the letter & spirit of the 400 ft. AGL rule for drones. If I choose to fly up a mountainside, say to a 2,500 foot summit at 300 ft. AGL, am I an outlaw? Also, in this discussion, if my Return To Home altitude is set for 30 meters Above Ground Level, will the drone hug the mountainside at 30 meters AGL returning to me? Or, will it suppose I meant 30 meters above it's launch altitude? Any support for your opinions would be appreciated.

Bored?

 

[BrianS]

legal: you can take off at your ground level. and only fly up to 400 above your head. BUT,,, if you are video a building, tower, etc. you are legal to fly 400 feet above that item.
no i am not a layer, no i did not sleep in a motels dirty bed last night. and internet advice is only worth what you paid for it.

My understanding of that rule is . . . You must stay within 400’ of the structure if it reaches over 400’ AGL. If you do, then you can fly 400’ over the upper height of that structure. There are some antennas that reach over a 1,000 AGL.

Is a mountain a structure?

That's another argument but as an example and if it were legal (National Park) lets consider Half Dome in Yosemite Park. The cliff face asends 4,800 ft or 1,460 meters nearly straight up. Therefore if you stayed within 400’ of Half Dome you could climb all the way up to 9,244’ MSL or 400’ AGL of the summit of Half Dome's which has an elevation of 8,844 ft/2,695 m MSL.

p.s. That’s my story and I’m sticking to it. Until a better argument comes along.

 

[sar104]

My understanding of that rule is . . . You must stay within 400’ of the structure if it reaches over 400’ AGL. If you do, then you can fly 400’ over the upper height of that structure. There are some antennas that reach over a 1,000 AGL.

Is a mountain a structure?

That's another argument but as an example and if it were legal (National Park) lets consider Half Dome in Yosemite Park. The cliff face asends 4,800 ft or 1,460 meters nearly straight up. Therefore if you stayed within 400’ of Half Dome you could climb all the way up to 9,244’ MSL or 400’ AGL of the summit of Half Dome's which has an elevation of 8,844 ft/2,695 m MSL.

p.s. That’s my story and I’m sticking to it. Until a better argument comes along.

This is a Part 107 rule. There is no altitude limit (yet) for Part 101.

 

[old man mavic]

hi fellow flyers all this discussion on the 400 ft rule AGL i presume stands for above ground level correct me if i am wrong so does that mean the surface of lets say a large body of water or the sea is classed as ground level we could go on and on about this just thought i would throw that into the mix happy flying

 

[Meta4]

does that mean the surface of lets say a large body of water or the sea is classed as ground level

Obviously it does.

 

[old man mavic]

thanks Meta4 just trying to inject some humour into the debate so many interpretations of what is correct

 

[draver]

Wow, if the info in that video is correct and accurate it would seem you could keep resetting the current aircraft location to a new home point as you were climbing. This seems like a way to ascend to whatever height you choose, and if you maintained an altitude below 400' AGL you would be in compliance unless I misunderstand the rule.

Bored?

Quite the opposite. If you read the thread I am interested in flying around and up a local mountain.
Turns out the joke might be on me. I just checked my maps and Mt. Hood is in Mt. Hood National Forest. Which may be a no fly zone? Or is there difference in restrictions between National Parks & National Forests? The B4UFly app has a list that includes The Grand Canyon, Yellowstone, etc. but I don't know if it is inclusive. Mt. Hood is not on that list, but it does list Mt. Rainier.

 

[Meta4]

Wow, if the info in that video is correct and accurate it would seem you could keep resetting the current aircraft location to a new home point as you were climbing. This seems like a way to ascend to whatever height you choose, and if you maintained an altitude below 400' AGL you would be in compliance unless I misunderstand the rule.

That wouldn't work.
When you save a home point, it only has latitude and longitude co-ordinates.
There is no altitude information.
So your indicated altitude would not change.

 

[Bigbird48]

I think its pretty simple keep the drone under 400 ft above the ground, doesn't matter where you stand its the drone you have to worry about.

 

[Vegasdad]

But now they have the birds set up to only go up to 392’ and if your building is higher than that it wont go unless you land and reset at least that’s what all my DJI birds do now.

 

[Meta4]

But now they have the birds set up to only go up to 392’ and if your building is higher than that it wont go unless you land and reset at least that’s what all my DJI birds do now.

Then you need to have a look at your Max Altitude setting.
The drone comes with a user-configurable Max Altitude setting which by default is set to approx 400 ft.
An update will reset that to the default settings.
That doesn't mean that you have to leave it at that though.

 

[theDRONEranger]

The 400 foot AGL makes sense in the respect, by limiting the drones to 400 permits for a 100 foot separation of fixed wing base. I am not a fixed wing pilot, but I did watch SKYKING when I was a kid! Truthfully, I have had several fixed wing friends inform me their base is 500. True or not, don’t know.

 

[Montana John]

"The CAA is pretty clear on this; any flight over 400ft AGL requires an exemption to be legal"

Is it that simple
AeroJ

?, look at the image and wording on page 4 of CAP1687

Quote: the 400 ft height above the surface requirement may be interpreted as being a requirement to
remain within a 400 ft distance from the surface, as shown in the diagram below

400ft From the surface is not the same thing as 400ft AGL

So "from the surface" requires drawing a perpendicular line from the nearest point of earth" as in the diagram, which could result in being 400 ft. horizontally from a vertical cliff face, but have no useful relation to altitude AGL?

 

[Montana John]

Then you need to have a look at your Max Altitude setting.
The drone comes with a user-configurable Max Altitude setting which by default is set to approx 400 ft.
An update will reset that to the default settings.
That doesn't mean that you have to leave it at that though.

I am very new to flying my Mavic Pro, and I have not yet tested out the Max Altitude limit. Do I understand that I can set the max to 1,000 feet if I so desire, and that will work until the next Go 4 update?

 

[Montana John]

The scenario you describe sounds fine to me in theory. In practice, Mavics only calculate their 400 AGL from the home point. So, to scale a mountain like in your scenario, you'd have to land, reset your home point, climb 400 feet higher, land, then repeat. You would need to keep following that process over and over to get to the top of the mountain.

Or just reset the Max Altitude?

 

[Lapeer20m]

To clarify, I assume you mean wherever your drone happens to be, now where the operator is located? I see videos of drones flying over the edge of cliffs for astounding footage, however it would seem that they are immediately in violation if the drop is more than 400 feet.

The part 107 rule is:

• Maximum altitude of 400 feet above ground level (AGL) or, if
higher than 400 feet AGL, remain within 400 feet of a
structure.

 

[sar104]

I am very new to flying my Mavic Pro, and I have not yet tested out the Max Altitude limit. Do I understand that I can set the max to 1,000 feet if I so desire, and that will work until the next Go 4 update?

You can set it as high as 500 m, which is 1640 ft.