WARNING Inspire near crash error close to NFZ

[Ikopta]

Feel need to share.
Was on a commercial shot this week. One location was very close to a NFZ near a football stadium. Still confused why they need it to be a 24/7NFZ(another story). Same day was filming outside a prison, which you would have though would have a NFZ, and it doesn't.

How ever, went to launch after pre flight checks. Had warning that near NFZ come up, which I was out side of the 500m radius shown on the DJIGO app.
Started the engines, started to take off and the craft self veered sharp right to avoid the NFZ, I had no control over this action.
If I had not set up the safe landing /takeoff area as per my CAA PFAW and had control of the area, I hate to think what could have happened to craft/property or people.

I have reported this event to DJI, and sent off this morning the request files and documents.
I have reviewed the flight log on the app, and you can see the stick movements clearly pull left, and the craft continuing right.
Have you heard of this happening else where?

Again, I was outside the 500m radius of NFZ, had all permissions etc, etc had every right to be there.
Was set to GPS mode, pre checks completed, full battery.
Tried again 10m away on the other side of the river, and everything worked fine.
Why did inspire pull away from NFZ? if so close, why did it even start the motors?
I attach a screen shot to show NFZ and craft location.

To further help, tried to copy the flight record (wish apple had a screen record!)
Dropbox - IMG_9021.MOV

 

[The Editor]

You do not say which versions of firmware/Go App you are running but unfortunately this is why GeoFence STILL hasn't been publically released. There are ongoing issues.
Currently, the NFZ areas are not being rendered correctly, however, what should have happened in this case is even allowing you to go airborne and then sensing you are within a NFZ should have resulted in a controlled decent and landing.
I am guessing here but what I think may have happened is you were absolutely on the perimeter of a NFZ. The GPS system only has an accuracy of a few meters and thus if you got airborne with a slight GPS drift on the NFZ coordinates the software allowed you to take off.
The circle/polygon of the NFZ may have then moved fractionally which effectively put you up against the 'wall' of the NFZ. This had the same effect as if you had flown full tilt into the NFZ wall - it will bounce you back and not allow you to fly further.
In your case I think it was the absolute threshold of NFZ and a series of bad luck events that meant the NFZ shifted very slightly which had the effect of throwing your craft out of the newly defined NFZ.
It is a strange anomoly I have not encountered previously, but one people should be aware of.
Thanks for posting this
Please let us know what response you get from DJI.

 

[Scotflieger]

Very useful warning. I assume that you are flying with the Public Beta GEO (or you are breaking your NDA). Many UK stadiums now appear on the latest Public GEO mapping as Authorisation Zones not (NFZs) and can be unlocked with the right beta app. I suspect you were within 50m of the boundary of the zone to get the un-commanded movement you experienced. The aircraft will normally stop and be held at 50m from the boundary in the hover on approaching an unlocked zone.

 

[Mad_angler1]

Pretty strange, was this public FW or GEO beta, taking off very close to an NFZ seems to give odd behaviour at times.

The old NFZ system also had a coned setup so in theory on the ground you would be out of it but as soon as you gain height it would push you further out but to do it as soon as you take off is odd indeed.

 

[Ikopta]

You do not say which versions of firmware/Go App you are running but unfortunately this is why GeoFence STILL hasn't been publically released. There are ongoing issues.
Currently, the NFZ areas are not being rendered correctly, however, what should have happened in this case is even allowing you to go airborne and then sensing you are within a NFZ should have resulted in a controlled decent and landing.
I am guessing here but what I think may have happened is you were absolutely on the perimeter of a NFZ. The GPS system only has an accuracy of a few meters and thus if you got airborne with a slight GPS drift on the NFZ coordinates the software allowed you to take off.
The circle/polygon of the NFZ may have then moved fractionally which effectively put you up against the 'wall' of the NFZ. This had the same effect as if you had flown full tilt into the NFZ wall - it will bounce you back and not allow you to fly further.
In your case I think it was the absolute threshold of NFZ and a series of bad luck events that meant the NFZ shifted very slightly which had the effect of throwing your craft out of the newly defined NFZ.
It is a strange anomoly I have not encountered previously, but one people should be aware of.
Thanks for posting this
Please let us know what response you get from DJI.

Latest version of firmware, updated on Monday 11th April, using the standard public DJI go app.

 

[Ikopta]

Pretty strange, was this public FW or GEO beta, taking off very close to an NFZ seems to give odd behaviour at times.

The old NFZ system also had a coned setup so in theory on the ground you would be out of it but as soon as you gain height it would push you further out but to do it as soon as you take off is odd indeed.

Using the Standard DJI Go app. As I said allowed me to take off, then about 0.5m of the ground pushed me right.

Very useful warning. I assume that you are flying with the Public Beta GEO (or you are breaking your NDA). Many UK stadiums now appear on the latest Public GEO mapping as Authorisation Zones not (NFZs) and can be unlocked with the right beta app. I suspect you were within 50m of the boundary of the zone to get the un-commanded movement you experienced. The aircraft will normally stop and be held at 50m from the boundary in the hover on approaching an unlocked zone.

Flying with the standard App, didn't know about the other version as, until now, NFZ never been an issue.

 

[Scotflieger]

Using the Standard DJI Go app. As I said allowed me to take off, then about 0.5m of the ground pushed me right.
Flying with the standard App, didn't know about the other version as, until now, NFZ never been an issue.

It looks like DJI has snuck the UK Stadiums in the latest public App release 2.7.2 as full NFZs with no get out of jail card. See DJI - Fly Safe: No Fly Zones

 

[Ikopta]

You do not say which versions of firmware/Go App you are running but unfortunately this is why GeoFence STILL hasn't been publically released. There are ongoing issues.
Currently, the NFZ areas are not being rendered correctly, however, what should have happened in this case is even allowing you to go airborne and then sensing you are within a NFZ should have resulted in a controlled decent and landing.
I am guessing here but what I think may have happened is you were absolutely on the perimeter of a NFZ. The GPS system only has an accuracy of a few meters and thus if you got airborne with a slight GPS drift on the NFZ coordinates the software allowed you to take off.
The circle/polygon of the NFZ may have then moved fractionally which effectively put you up against the 'wall' of the NFZ. This had the same effect as if you had flown full tilt into the NFZ wall - it will bounce you back and not allow you to fly further.
In your case I think it was the absolute threshold of NFZ and a series of bad luck events that meant the NFZ shifted very slightly which had the effect of throwing your craft out of the newly defined NFZ.
It is a strange anomoly I have not encountered previously, but one people should be aware of.
Thanks for posting this
Please let us know what response you get from DJI.

thanks for the reply, will let you know what they say.

 

[Ikopta]

I'm guess the NFZ will get tighter after todays news that a plane landing may have been hit with a drone. There is a place for them. For the untrained, inexperienced and Idiots that feel the rules are not for them. Time for a register/licence system me thinks. At they moment those of us with PFAW/insurance etc are the only traceable entities, and we are the group who are more likely to be flying legal & safe. Heavy sigh.

 

[The Editor]

It looks like DJI has snuck the UK Stadiums in the latest public App release 2.7.2 as full NFZs with no get out of jail card. See DJI - Fly Safe: No Fly Zones

View attachment 7996

This keeps changing all the time (along with colour schemes) and DJI really can't seem to make up their minds.
One day there are authorised and 'enhanced' zones like AIAA' and then they are gone!
The problem with this blanket Poofball stadium ban is this prevents legitimate work being carried out on these areas like roof inspections, surveys etc and therefore hinders certified operators carrying out their day to day work.

 

[seanmclean]

NFZ will not command the aircraft away from the edge of the zone. It will warn you, and then land it.

 

[Ikopta]

NFZ will not command the aircraft away from the edge of the zone. It will warn you, and then land it.

Thats what I thought, seems a glitch that makes it not the case if taking off close to a NFZ, defo pushed me away from the NFZ, see the flight record & stick movement. Dropbox - IMG_9021.MOV

 

[The Editor]

NFZ will not command the aircraft away from the edge of the zone. It will warn you, and then land it.

Have you tried accelerating at full tilt into a NFZ threshold (ignoring the warnings and continuing at full stick?)
The same way that if you set up a distance limit of say 100m and then fly full speed away from you? It will actually fly past the 100m 'barrier' due to inertia of the aircraft at 40mph. The Inspire will then 'rebound' back into the 100m zone you have set. You will not then be able to fly outside of this perimeter.
Clearly what ikopta experienced was an anomaly but reaching the limit of any Geo imposed boundary can give the impression of a rebound if sufficient velocity is achieved before reaching the 'fence'

 

[seanmclean]

Have you tried accelerating at full tilt into a NFZ threshold (ignoring the warnings and continuing at full stick?)
The same way that if you set up a distance limit of say 100m and then fly full speed away from you? It will actually fly past the 100m 'barrier' due to inertia of the aircraft at 40mph. The Inspire will then 'rebound' back into the 100m zone you have set. You will not then be able to fly outside of this perimeter.
Clearly what ikopta experienced was an anomaly but reaching the limit of any Geo imposed boundary can give the impression of a rebound if sufficient velocity is achieved before reaching the 'fence'

My understanding is that the fencing around NFZs is different than one that you set (i.e., horizontal distance limit). It will certainly arrest the aircraft if you exceed your set distance, but my understanding (and has been said by DJI), is that if you enter a NFZ and ignore the warnings, the aircraft will autoland.

 

[Ikopta]

As an Update, really getting frustrated with DJI Technical. I have now emailed the flight records etc for the third time, which after a few days they then claim they can't open. This is straight from the ipad, as per their info sheet they keep emailing.Had plenty of questionnaires through to rate the service though.
Really concerned that if they do not address this, someone may get hurt.

 

[chris digata]

Seems they are playing for time.. but I dont agree with these enforced NFZ`s , they should be just warnings where the craft just hovers until you click and agree to proceed.
Any geo fencing is going to cause more safety problems and if App based if an idoit wants to fly over the football he will use some crap aircraft or another app if any app at all

 

[Ikopta]

Seems they are playing for time.. but I dont agree with these enforced NFZ`s , they should be just warnings where the craft just hovers until you click and agree to proceed.
Any geo fencing is going to cause more safety problems and if App based if an idoit wants to fly over the football he will use some crap aircraft or another app if any app at all

Good point, hover would be the answer.
Not sure I can trust the DJI for professional work. Which now makes it an expensive toy.

 

[Ikopta]

So, to update......still no update from DJI........no request to resend data, so can only assume they now can follow their own instructions........

 

[Ikopta]

So had reply from DJI.
They said "don't fly near NFZ's". MMmmmm Helpful.
Here is their email, just in case you think I joke:

Dear Customer,
Thank you for contacting DJI technical support.
Sorry for being late.
We have tried many times on your case.
Went to launch Inspire out side of NFZ. The DJIgo app warned that near NFZ. Started motors, completed pre flight check.
Push left stick up to take up.
Craft raised about 0.5m and started to veer sharply right away from NFZ into safety barrier.
Pilot immediately pulled right stick left to pull away from barrier, craft continued to pull right away from NFZ by its self, Safety issue as pilot had no control of craft at this point.
Pilot pulled down on left stick to land and cut power.
When moved launch site further away from NFZ, issue did not occur.
So, our engineer just sggest you to avoid the NFZ, then the problem will be solved.
Thanks for you understanding.
Best regards,
DJI Support EU

 

[Scotflieger]

Very helpful. I assume they will be widely publicising this advice.