"air corridor".
There's an interesting thread on mavicpilots, https://mavicpilots.com/threads/ ... page-2#post-1507393

The summary of the thread is that the drone, Mini 3 Pro, was launched under an "air corridor" and subsequently flown out from underneath the 'corridor'. An RTH was triggered whilst the drone was in unrestricted airspace and the RTH height was above the bottom of the 'corridor,' consequently the drone got 'stuck' at the side of the corridor until the critical battery landing started. Once the drone was below the height of the 'corridor' the pilot was able to 'regain' control of the drone and got it to safety, it had been 'stuck' over the sea.

This is known behaviour.

What makes things interesting is that the flight log was posted and someone noticed
a) that whilst the drone was below the 'corridor' the maximum permissible height, shown in the log, was reduced to the height of the floor of the 'corridor' and
b) when the drone was in unrestricted airspace the drone's maximum permissible height was increased, as shown in the log and corresponding behaviour, to that presumably set by the pilot.

It is also stated that the app (or something) will not permit the RTH height to be set to higher than the maximum height set by the pilot.
Yet all the way through the flight log the RTH height has one value, above the height of the floor of the 'corridor', and, in this particular flight, equal to the pilot's maximum permissible height.

A few pilots have had problems when running into the side of an "air corridor" and the point of this post is to ask.
  
Since DJI can apparently program something to temporarily reduce the maximum permissible height, could they change the programming so that the maximum permissible height does not jump 'vertically' at the wall of the 'corridor' but rather it 'ramps/slopes' the change over a few metres or tens of metres. The slope/ramp being, of course, wholely outside the 'corridor'?

Since, from the log, it appears that the drone cannot exceed the maximum height limit shown in the log, such a change should? force a drone approaching such a wall downwards so that it could pass under the 'corridor'. In addition would it be possible to program a return to the drone's 'original' height once the drone was clear of the 'corridor' or, the pilot asked if they wanted the drone to return to that height / continue at the current height... etc.?

I am not sure what equipment controls this behaviour but if the programming is on the drone it would also mean that the programming could be followed in the event of a disconnection.

I think it would be best if the descent and climb slopes were steep just incase, when not under the 'corridor', there were collision risks at the reduced height.

Had a read through that thread and in my opinion, it's down to bad situational awareness from the pilot. They've noted there's a 60m altitude limit and opted to RTH with critical battery with an RTH value of 65m, which means that the drone will not fly through the NFZ.

I've personally flown this exact type of airspace, flying under a 60m restriction and using the other side to gain height. I generally keep my RTH value at about 40m (pointless wasting energy going up too high), so I knew that wouldn't be an issue.

The thing that always bothers me is that people overuse the RTH because they're either lazy or lose orientation of where they are in the sky. I can count on one hand the number of times I've used it in all my time flying drones. It's an emergency feature, not a lazy means to get you home, especially when the battery is critical like this guy got to. Once you've left it so late to initiate the RTH in an environment with NFZ altitude restrictions, you're bound to run into problems.

This is a perfect example of the Swiss Cheese model accident causation, all the risks lined up to nearly cause a catastrophic loss of the drone.

That it was pilot error is not really in doubt but that is not the point of this thread. The point is to see if it would be feasible/possible to change the programming so that, as the drone approaches such a wall, it would descend enough to pass under the corridor.

From Suren's recent post in that thread #31, it seems that this capability is possible and exists with the Mavic 3 though it doesn't climb after coming out from under the 'corridor'.

Sean-bumble-bee Posted at 12-31 03:57
That it was pilot error is not really in doubt but that is not the point of this thread. The point is to see if it would be feasible/possible to change the programming so that, as the drone approaches such a wall, it would descend enough to pass under the corridor.

From Suren's recent post in that thread #31, it seems that this capability is possible and exists with the Mavic 3 though it doesn't climb after coming out from under the 'corridor'.

But then we'll probably end up with a thread that says "My drone descended onto a building when I RTH WTH DJI!"

They put these safety features in place and I believe that they're good ones. It's down to the common sense and understanding of each pilot to assess where they're flying and understand how the drone will behave in different circumstances. It baffles me that people go fly these drones with little to no experience and then kick off about how the drone behaved abnormally when they've got so little understanding or comprehension about how the safety systems operate or affect each other.

CloudVisual Posted at 12-31 04:25
But then we'll probably end up with a thread that says "My drone descended onto a building when I RTH WTH DJI!"

They put these safety features in place and I believe that they're good ones. It's down to the common sense and understanding of each pilot to assess where they're flying and understand how the drone will behave in different circumstances. It baffles me that people go fly these drones with little to no experience and then kick off about how the drone behaved abnormally when they've got so little understanding or comprehension about how the safety systems operate or affect each other.

Sadly ...... all too true ..... and I'd bet they'd scream it from the roof tops too ......  if the drone continues at the reduced height once it is clear of the corridor.
But that is why I suggested the climb once the drone is clear of the corridor or 'at least' offering the option to climb.
A case of "you can please some of the people......" I think.
There will always be people who won't accept that a problem was caused by their own actions, we see it all the time here and they tend to be quite vociferous about it being someone else's fault and not their's.


I'd agree that too many don't read the manual but I also think a large number of people miss the significance of small phrases, especially if they are forced to read a manual in a language that is foreign to them.
Missing the significance of a phrase has caught me out several times and I am not 'thick', (well ... most of the time ) and I was reading in my native and only language.  

Perhaps DJI might be able to put a large warning on screen if the drone is physically being stopped in this way. "Unable to RTH, take control and DESCEND to below 60M". Alternatively a recommendation to lower the RTH altitude at CSC stage if flying close to a low overhead restricted zone.

There's the usual warning which does pop up to say that the RTH path crosses through a NFZ, but I bet you 99% of people pay no attention to this. DJI would need to put something more obvious on the screen.

There's only so much hand-holding they can do before we start to feel like we're being treated like babies and don't know what we're doing with the drones.