400 ft max altitude

[jac1957]

If I am not mistaken, the 400 ft altitude is the distance from the ground to the drone, not the distance above the pilot and controller. An example would be, you are standing on the edge of a 200 ft cliff. So, if you launch your drone straight above you to 400 ft you are within legal distance. Then you fly the drone off the edge of the cliff over the valley below. Now the drone is considered to be 600 ft above ground. That is my understanding of the rule.

 

[mnpaslay]

If I am not mistaken, the 400 ft altitude is the distance from the ground to the drone, not the distance above the pilot and controller. An example would be, you are standing on the edge of a 200 ft cliff. So, if you launch your drone straight above you to 400 ft you are within legal distance. Then you fly the drone off the edge of the cliff over the valley below. Now the drone is considered to be 600 ft above ground. That is my understanding of the rule.

You can be within 400 feet of a structure or cliff and still be 400 feet above it. Using your example if you are on a cliff 200 feet high you could fly up 400 feet above you. Then if you fly over the edge you are at 600 feet above ground, which is acceptable within 400 feet of the edge of the cliff. After you are more than 400 feet away from edge of the cliff then you are non-compliant.

 

[sar104]

You can be within 400 feet of a structure or cliff and still be 400 feet above it. Using your example if you are on a cliff 200 feet high you could fly up 400 feet above you. Then if you fly over the edge you are at 600 feet above ground, which is acceptable within 400 feet of the edge of the cliff. After you are more than 400 feet away from edge of the cliff then you are non-compliant.

That is often assumed to be the case but not stated anywhere in FAA regulations, which simply refer to AGL. It is correct in some countries, such as the UK, where the CAA has explicitly clarified it with this diagram:

 

[DanMan32]

The letter of the law is 400ft directly below, but in practice, I doubt anyone would fault you if you were suddenly 600ft AGL just 100ft from the cliff. You can't instantly drop 200ft right at the cliff face, at least not safely, nor would a plane be so close to the cliff.

The structure clause doesn't apply to recreational flights.

 

[hactick]

The letter of the law is 400ft directly below, but in practice, I doubt anyone would fault you if you were suddenly 600ft AGL just 100ft from the cliff. You can't instantly drop 200ft right at the cliff face, at least not safely, nor would a plane be so close to the cliff.

The structure clause doesn't apply to recreational flights.

Can you clarify the structure clause not applying to recreational flights? I’ve never heard this distinction before.

 

[BigAl07]

Can you clarify the structure clause not applying to recreational flights? I’ve never heard this distinction before.

Only Part 107 operations have the "luxury" of flying 400' over a structure. This is to allow for inspections etc of towers and other tall structures. No need for such allowances for Hobby/Recreational operations. It's a 400' hard ceiling.

 

[BigAl07]

The letter of the law is 400ft directly below, but in practice, I doubt anyone would fault you if you were suddenly 600ft AGL just 100ft from the cliff. You can't instantly drop 200ft right at the cliff face, at least not safely, nor would a plane be so close to the cliff.

The structure clause doesn't apply to recreational flights.

I have to respectfully disagree here. IF there was an incident you would be at fault for not maintaining 400' AGL. Unless there is an incident or a complaint odds are no one will ever know the difference but if there is and it's proven then you violated the ceiling. It's pretty cut & dried IMHO.

 

[SirLancelot]

I have to respectfully disagree here. IF there was an incident you would be at fault for not maintaining 400' AGL. Unless there is an incident or a complaint odds are no one will ever know the difference but if there is and it's proven then you violated the ceiling. It's pretty cut & dried IMHO.

How can you be 400 feet up and still have VLOS you must have better eyes then me.

 

[BigAl07]

How can you be 400 feet up and still have VLOS you must have better eyes then me.

I can see all of my sUAS at 400’ except for the smallest of them (Spark etc).

Granted if you don’t have great light/sky conditions or you take your eyes off it can be challenging.

I wasn’t saying to fly at 400’ I was stating that if you go over 400’ you’re outside the regs as a hobbyist.

 

[Gindra]

If I, as a Part 107 pilot, need to inspect a tower I can fly up to 400' above the top of the tower as long as I remain within a 400' radius of the tower. I think it is this caveat that many then extrapolate to include the OP's scenario of flying over the edge of a cliff.