HELP!!! Using 400' AGL as my ceiling hypothetically

[Rich QR]

This is not legally acceptable at this point in time. You are not allowed to fly up a sheer cliff in the US.

But you ARE allowed to fly up any cliff that exists in FAA jurisdiction. All of the cliffs taller than 400' are sloped such that flight over them could be accomplished without ever exceeding 400' AGL. Either they're not quite vertical, or they're shorter than 400', or they're outside of the USA.

EpicFlight is, at least partly, talking about the law as courts interpret it. Courts do not issue precedent-setting opinions on hypothetical cases that don't come before them. So while the idea of being unable to scale a 401' vertical cliff is an interesting and convenient mental exercise that makes it clear exactly what the meaning of "AGL" is, it is not something that the courts will ever concern themselves with, unless the topography of the US changes dramatically.

 

[MS Coast]

But you ARE allowed to fly up any cliff that exists in FAA jurisdiction. All of the cliffs taller than 400' are sloped such that flight over them could be accomplished without ever exceeding 400' AGL. Either they're not quite vertical, or they're shorter than 400', or they're outside of the USA.

EpicFlight is, at least partly, talking about the law as courts interpret it. Courts do not issue precedent-setting opinions on hypothetical cases that don't come before them. So while the idea of being unable to scale a 401' vertical cliff is an interesting and convenient mental exercise that makes it clear exactly what the meaning of "AGL" is, it is not something that the courts will ever concern themselves with, unless the topography of the US changes dramatically.

Nothing like a little fact, reality, and practicality to resolve an issue.

Or to point out that there is no issue to fret over.

 

[Yorkshire_Pud]

If I am reading CFR 14 §91.119 properly that distance would be 500’ unless over a congested area (yellow on sectional maps) then it would be 2000’.

Sorry I am even more confused now, so, to keep it simple for this dummy.

 

[LoudThunder]

I am a Recreational Flyer and I like the String analogy, and that depending on the Maximum established flight altitude established, be it 100', 200', or whatever, up to 400', my mythical string must be touching the ground, not the top of a building, a tower, or other non-natural structure.

 

[MS Coast]

Sorry I am even more confused now, so, to keep it simple for this dummy.

CFR 14 §91.119 applies to manned aircraft, not drones.

There is no regulation for drones in the US that is expressed in altitude above the takeoff point. The maximum is 400' AGL, above the ground level directly below the drone. The string analogy @LoudThunder mentioned is a good way to visualize the allowed altitude when flying over higher and lower terrain.

There's an exception to the 400' rule for operation by a Part 107 rated (commercial) pilot, allowing flight up to 400' above a structure as long as the aircraft remains within 400' horizontally of the structure.

 

[Yorkshire_Pud]

CFR 14 §91.119 applies to manned aircraft, not drones.

There is no regulation for drones in the US that is expressed in altitude above the takeoff point. The maximum is 400' AGL, above the ground level directly below the drone. The string analogy @LoudThunder mentioned is a good way to visualize the allowed altitude when flying over higher and lower terrain.

There's an exception to the 400' rule for operation by a Part 107 rated (commercial) pilot, allowing flight up to 400' above a structure as long as the aircraft remains within 400' horizontally of the structure.

Thanks, I think it is safe to say that there are a few loops in this thread that are causing some confusion.
My recent questions directed to DoomMeister concern the sentence "You are not allowed to fly up a sheer cliff in the US." written by him? in post #57 on page 3. That sentence could be taken as meaning that, in the US, it is not permissible to fly a drone up ANY sheer cliff no matter what its height may be, be it 10ft or 2000ft.
If that were correct then the metaphorical drone of my diagram would be limited in height to the top of the scree slope i.e. nigh on 0ft AGL or 375ft above the take off point.
However I believe that DoomMeister's sentence "You are not allowed to fly up a sheer cliff in the US." was meant to mean something like "In the US you are not allowed to send a drone higher than 400ft above the base of a sheer cliff", I was trying to check whether the latter was DoomMeister's intention but it seems to have lead elsewhere.
"In the US you are not allowed to send a drone higher than 400ft above the base of a sheer cliff" is my understanding of US law and if correct, it fits 'my' 'use of the weighted sting' in post #7. It would also mean that my metaphorical drone of post #68 is permitted to climb to 400ft above that little ledge at the top of the scree slope, which would also equate to 775ft above the take off point.
I am aware that all height limits for a recreational pilots flying in the USA are AGL. I included the take off point in my diagram as a common reference point and because it is the basis of the height seen by the drone's pilot in the control app.

 

[DoomMeister]

However I believe that DoomMeister's sentence "You are not allowed to fly up a sheer cliff in the US." was meant to mean something like "In the US you are not allowed to send a drone higher than 400ft above the base of a sheer cliff",

That is correct sir.

 

[Yorkshire_Pud]

That is correct sir.

Thanks DoomMeister.

 

[MS Coast]

Thanks, I think it is safe to say that there are a few loops in this thread that are causing some confusion.
My recent questions directed to DoomMeister concern the sentence "You are not allowed to fly up a sheer cliff in the US." written by him? in post #57 on page 3. That sentence could be taken as meaning that, in the US, it is not permissible to fly a drone up ANY sheer cliff no matter what its height maybe, be it 10ft or 2000ft.
If that were correct then the metaphorical drone of my diagram would be limited in height to the top of the scree slope i.e. nigh on 0ft AGL or 375ft above the take off point.
However I believe that DoomMeister's sentence "You are not allowed to fly up a sheer cliff in the US." was meant to mean something like "In the US you are not allowed to send a drone higher than 400ft above the base of a sheer cliff", I was trying to check whether the latter was DoomMeister's intention but it seems to have lead elsewhere.
"In the US you are not allowed to send a drone higher than 400ft above the base of a sheer cliff" is my understanding of US law and if correct, it fits 'my' 'use of the weighted sting' in post #7. It would also mean that my metaphoerical drone of post #68 is permitted to climb to 400ft above that little ledge at the top of the scree slope, which would also equate to 775ft above the take off point.
I am aware that all height limits for a recreational pilots flying in the USA are AGL. I included the take off point in my diagram as a common reference point and because it is the basis of the height seen by the drone's pilot in the control app.

I think we're completely on the same page. I agree with everything you said.

The only confusion comes from the question posed in your diagram. "In the USA what is the legal height limit above the takeoff point for a recreational pilot i.e. not part 107 etc."

You're spot on about the regulation in the US. I understand now that you meant AGL but typed something else. It's an over-60 thing; happens to me, too. Cheers.

 

[Vic Moss]

Have reviewed all relevant court and administrative rulings to make this statement so definitively?

And is the letter of the law solely what defines what is legal?

I'm all for following the law, and absolutely for safety. However I don't believe bullying and trying to scare people that they're going to be behaving dangerously if they make a completely harmless technical violation of the rules advances either objective. This is lying at worst, obnoxious nannyism at it's best.

AGL is ALG, not BVL (Beside Vertical Limit, yes that's made up).

Technically and legally you cannot fly down a vertical cliff that is over 400' high. "Structure" is strictly man made. I've brought this up many times in discussion with the FAA. And even many of them agree it doesn't make sense, but that's how the law is currently written.

Is it perfectly safe to fly up a cliff that is over 400'? Sure, almost always. But it's not legal.

The better question for this discussion would be if anyone cares. No, the FAA would not likely care. That is unless something happens. And that's always the caveat.

So you need to decide about the benefits of risk v. reward. Does the safety of the flight override the legality? That's a question only the RPIC or recreational flyer can determine for themselves.

But they better be right if something goes wrong.

 

[MikeeS]

It is simple. It states AGL (Above Ground Level). If you take off from sea level (0 MSL) and fly up to the top of a 2000 ft peak, the maximum altitude you can fly is 2000 + 400 or 2400 ft MSL (Mean Sea Level) but your are still at 400 ft AGL.

 

[dirkclod]

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[Yorkshire_Pud]

It is simple. It states AGL (Above Ground Level). If you take off from sea level (0 MSL) and fly up to the top of a 2000 ft peak, the maximum altitude you can fly is 2000 + 400 or 2400 ft MSL (Mean Sea Level) but your are still at 400 ft AGL.

Being a bit pedantic, if you are flying that flight with an unhacked DJI drone I doubt you could get above 1640ft MSL, due to the 500m above take off point hard ceiling.

 

[classGairspace]

Your understanding is correct. This has been discussed many times on the forum in the past couple of years. The altitude limitation is 400' AGL, above ground level. It applies at the location of the drone. Takeoff location has no bearing.

Takeoff location has no bearing except the controller will show the AGL based on that point of reference. I only mention it because things then get confusing when traveling over hills and valleys from that point.

 

[Yorkshire_Pud]

no bearing except the controller will show the AGL based on that point of reference. I o

Meaning no offense but the phrasing of that causes confusion.
AGL has nothing whatsoever to do with the heigh above the take off point and refers solely to the height of the drone above the ground beneath the drone. Saying AGL in connection with the height above the take off point confuses people.
It would a bit like Neil Armstrong referring to the height of the Lunar Lander above the surface of the Moon by mentioning the distance from Earth.

 

[MikeeS]

Meaning no offense but the phrasing of that causes confusion.
AGL has nothing whatsoever to do with the heigh above the take off point and refers solely to the height of the drone above the ground beneath the drone. Saying AGL in connection with the height above the take off point confuses people.
It would a bit like Neil Armstrong referring to the height of the Lunar Lander above the surface of the Moon by mentioning the distance from Earth.

What I was trying to show is the maximum 400 ft a drone can fly is 400 ft above the spot the drone is currently at.

 

[GFields]

This thread has long run its course