I thought I understood permissable flight altitude?

[vsguru]

Your drone has no idea how far it is away from the ground -- just the takeoff point. Therefore your "ceiling" as far as the drone knows will be 400' above your takeoff point (if that's what you have your UI set to). While will be 900' above the river basin. In theory, if you are within 400' horizontally of the cliff, you are good to stay 400' above that level in a similar way that you can fly above 400' AGL if you are within 400' of a building (using the building height as the new "ground level").

That makes perfect sense! Thanks so much FoxFlight2020.

 

[DoomMeister]

Your drone has no idea how far it is away from the ground -- just the takeoff point. Therefore your "ceiling" as far as the drone knows will be 400' above your takeoff point (if that's what you have your UI set to). While will be 900' above the river basin. In theory, if you are within 400' horizontally of the cliff, you are good to stay 400' above that level in a similar way that you can fly above 400' AGL if you are within 400' of a building (using the building height as the new "ground level").

That 400 foot lateral distance only applies to Part 107 flights, not recreational flights.

 

[FoxFlight Drone Video]

That 400 foot lateral distance only applies to Part 107 flights, not recreational flights.

Thus "in theory". In fact, recreational pilots are limited to 400 AGL at all times. However, the reason I brought this up (in theory) is that is is ridiculously presumptive to think that if the cliff drops straight off, you have to drop your drone straight off within inches of the cliff face. The point was that you can descend off the cliff into the valley as long as you aren't being stupid about it.

 

[sar104]

Thus "in theory". In fact, recreational pilots are limited to 400 AGL at all times. However, the reason I brought this up (in theory) is that is is ridiculously presumptive to think that if the cliff drops straight off, you have to drop your drone straight off within inches of the cliff face. The point was that you can descend off the cliff into the valley as long as you aren't being stupid about it.

A couple of points:

Firstly - note that even Part 107 doesn't allow 400 ft laterally from cliffs - that only applies to structures. 14 CFR §91.119 (b) and (c) give a clue why that would be:

§91.119 Minimum safe altitudes: General.​

Except when necessary for takeoff or landing, no person may operate an aircraft below the following altitudes: ​

​

(a) Anywhere. An altitude allowing, if a power unit fails, an emergency landing without undue hazard to persons or property on the surface. ​

​

(b) Over congested areas. Over any congested area of a city, town, or settlement, or over any open air assembly of persons, an altitude of 1,000 feet above the highest obstacle within a horizontal radius of 2,000 feet of the aircraft. ​

​

(c) Over other than congested areas. An altitude of 500 feet above the surface, except over open water or sparsely populated areas. In those cases, the aircraft may not be operated closer than 500 feet to any person, vessel, vehicle, or structure.​

Manned aircraft are not permitted within 500 ft of a structure, which is why it should be safe to fly a drone out to 400 ft, vertical or lateral. But that restriction does not apply to terrain - there is nothing preventing manned aircraft operating within 400 ft of a cliff in uncongested areas.

Secondly, if the cliff is vertical, then the question of how to treat that under Part 107 or the recreational exception is a good one. I've never seen it addressed by the FAA, but I've always worked on the assumption that as long as you are closer to the cliff than it would be reasonable to find a manned aircraft, then that should be fine.

 

[FoxFlight Drone Video]

but I've always worked on the assumption that as long as you are closer to the cliff than it would be reasonable to find a manned aircraft, then that should be fine.

Yep. People who make rules and laws and regulations very often fail to think of Everything (capital E intended). The bottom line is, don't be dumb.

 

[sar104]

Yep. People who make rules and laws and regulations very often fail to think of Everything (capital E intended). The bottom line is, don't be dumb.

I'm quite sure that they thought about it. But I suspect that they took a common FAA approach - leave it somewhat vague and undefined so that they have leeway to apply a variety of other criteria to determine if a flight is safe.

 

[Fat Pappy]

When you increased the maximum height to 1600ft did it stay there? I have a recollection of seeing an adjustment not 'take' but I can not remember the circumstances.
Perhaps try working up in increments over the 400ft 'norm' to see if there is some threshold?

My MA2 had this issue. I had to reboot my phone to get it to work right. Was not really a drone issue but a phone issue.

 

[Meta4]

My MA2 had this issue. I had to reboot my phone to get it to work right. Was not really a drone issue but a phone issue.

If you change the Max Altitude limit, you have to have the drone connected because it is stored in the drone.
It should stay at whatever you change it to, but could be reset to default values if you update your firmware.