Questions about altitude zones

[Deleted member 94047]

Hello!

I am planning to shoot a few pictures and videos of these two tiny island monasteries in Lake Tana (Bahirdar, Ethiopia). Problem is, they are inside an Altitude Zone; one that limits max height to 60m.



I don't think I can get a full birds eye view of these islands from that height. But I am still set on getting there by boat, flying to the extent that DJI's Geozone fencing would allow me and shooting these islands as best as I can. I would however like to know (with as much certainty as possible) what I can and cannot do in this altitude zone beforehand. So I would immensely appreciate your thoughts on these two questions.

1. Can altitude zones be unlocked (I mean in the self authorization way)? I already have a self-authorization unlock for the blue zone surrounding the airport valid for next weekend when I plan to do the shoot but I don't suppose this will apply to the altitude zone? Or does it?

2. What will happen if I (accidentally) exceed the maximum height? Will the AC simply descend back to a height below the max ceiling or is it at all possible that this would result in it getting stuck there (much like what I have read can happen if your AC enters or encounters a no fly zone during RTH).

Will be thankful for any assistance in this.

 

[dawgpilot]

1) I don't believe they can be unlocked. Altitude zones are designated by DJI to ensure the safety of takeoff/landing paths to local airstrips.

2) You can't accidentally exceed the maximum height. The drone is programmed not to allow you to fly higher than the designated altitude zone. It's possible for your drone to get stuck if a RTH would require it to cross an altitude zone (there is an on-screen warning about this), so be careful about possible RTH situations that might occur around those areas. (set an appropriate RTH height and be careful about flying at such a distance that you might suffer a disconnection)

 

[Thomas B]

Hello!

I am planning to shoot a few pictures and videos of these two tiny island monasteries in Lake Tana (Bahirdar, Ethiopia). Problem is, they are inside an Altitude Zone; one that limits max height to 60m.

View attachment 87626

I don't think I can get a full birds eye view of these islands from that height. But I am still set on getting there by boat, flying to the extent that DJI's Geozone fencing would allow me and shooting these islands as best as I can. I would however like to know (with as much certainty as possible) what I can and cannot do in this altitude zone beforehand. So I would immensely appreciate your thoughts on these two questions.

1. Can altitude zones be unlocked (I mean in the self authorization way)? I already have a self-authorization unlock for the blue zone surrounding the airport valid for next weekend when I plan to do the shoot but I don't suppose this will apply to the altitude zone? Or does it?

2. What will happen if I (accidentally) exceed the maximum height? Will the AC simply descend back to a height below the max ceiling or is it at all possible that this would result in it getting stuck there (much like what I have read can happen if your AC enters or encounters a no fly zone during RTH).

Will be thankful for any assistance in this.

I recommend contacting the airport for permission to fly higher.

 

[Deleted member 94047]

1) I don't believe they can be unlocked. Altitude zones are designated by DJI to ensure the safety of takeoff/landing paths to local airstrips.

2) You can't accidentally exceed the maximum height. The drone is programmed not to allow you to fly higher than the designated altitude zone. It's possible for your drone to get stuck if a RTH would require it to cross an altitude zone (there is an on-screen warning about this), so be careful about possible RTH situations that might occur around those areas. (set an appropriate RTH height and be careful about flying at such a distance that you might suffer a disconnection)

Thanks for the reply @dawgpilot. I am still uncertain about what will happen if the AC exceeds the height ceiling but I will be cautious and not climb above 50m (although i don't think I can make good shots at that height).

 

[Deleted member 94047]

I recommend contacting the airport for permission to fly higher.

Ideally that would have been the way to go. But I know that they will ask for papers (every bureaucrat in this country loves asking for papers). So that is going to be futile. Will have to fly under 60m I guess.

 

[DanMan32]

Thanks for the reply @dawgpilot. I am still uncertain about what will happen if the AC exceeds the height ceiling but I will be cautious and not climb above 50m (although i don't think I can make good shots at that height).

How were you expecting to or thinking you could end up exceeding the height ceiling?

The idea of the ceiling is that when you reach that altitude, it won't go any higher.

 

[Deleted member 94047]

How were you expecting to or thinking you could end up exceeding the height ceiling?

The idea of the ceiling is that when you reach that altitude, it won't go any higher.

GPS inaccuracies, momentum and such. Or am I being completely ignorant here?

 

[DanMan32]

OK, so you're saying you start out outside of the zone and above the zone ceiling, and enter the zone? I thought you meant taking off within the zone which would mean you're already limited.

It probably won't let you enter into the zone without descending first.

 

[Deleted member 94047]

I am considering both (entering into the Altitude Zone and taking off within the AZ) at the moment and haven't decided yet. But in either case, and especially the later, I am worried that the Geo-fencing system may discover the AC is in a restricted flight zone (in this case above 60m) after the AC has already entered it. I take it the AC takes its altitude reading from GPS and/or the onboard barometer which are not exactly precise or instantaneous. Assume the height readings of the AC change from 59m to 61m as either of these two instruments adjust their values or the momentum of the AC's upward movement takes it to a height of 61m before the FC's break kicks in. What happens then? Will the FC simply notify me to descend below the height ceiling, will the FC force the AC to descend below the ceiling and hover, or will it realize that the AC is in a place it should not be and initiate a forced landing? Is there a chance that the AC will simply freeze where it is since it is in a zone it cannot/should not fly in any direction, up or down?

Basically, I am wondering what the sop/expected behavior of the AC is in the unlikely event of it finding itself above the height ceiling in a height limited zone. The one way I can think of doing this safely is not to climb above 50m even if that means I won't get the shots I want. I would have liked to fly as close to the ceiling as I can but I think it better not to do that unless i am reasonably certain of what would happen in the what if scenario I presented above.

P.S. I may be overthinking this.

 

[DanMan32]

The system is going to go by what it thinks is the height and not actual height if inaccurate. After all, how could it know it is inaccurate?

If you're already in the zone, it won't let you climb above the ceiling.

If you are not in the zone but you attempt to do so while it thinks you are above the limit, I would believe it won't let you enter until you descend.

It would be difficult to test what it would do if somehow you do manage to be in the zone above the altitude limit as it would be difficult to safely circumvent the limit, then allow it. Temporary GPS loss is the only way I could figure you could do it.

 

[Thomas B]

Go to the point in question at the edge of the change. Climb and se if it lets you go above the restriction (likely won’t). Then try entering the next zone. < 5 min. Questions answered first hand and no speculation needed.