So I was out on the beach today withy 2 boys and the drone, a little windy but not too bad (around 9-10 knots) the drone was flying happily until i received an error message stating that there was magnetic field interference, the drone then went into ATTI mode and began to drift quite quickly on the wind and the only control I could use was to lower the aircraft until it hit the sand, I could not stop the roters from spinning once on the ground and it was trying to lift again it eventually flipping roters down snapping 2 of them.
I have been warned about drone fly away and have been advised to use an app called magnetoligy which I did and got the following pre flight reading
I also checked on UAV Forecast and there was no warnings on there.
It looks as though I have been quite lucky as I was only at 30 ish mtrs to begin with and almost directly above my head. And the only damage I have found so far is to the rotors and sand ingress that I will clean a before I take it anywhere.
So I gues all I am asking is did I miss something?
have i done something wrong?
Could I have done anything different other than ditch it into a sand dune?
Hmm, certainly an odd one. Without seeing the flight records it’s hard to say for certain, everything would be stabbing around in the dark, guessing.
It’s unlikely to be the KP index, so we’ll discount that.
It’s possible that there was an area of mag interference or the drone needed calibrating before take off. If this isn’t done, then it will enter atti mode once away from the source of interference, because it doesn’t know where it is in time and space because, for example, due to mag interference it thought it was pointing north, then when away from it, finds itself pointing south, so one of the sensors can’t agree with the GPS sensor. Or you took off without enough GPS fixes and when it gained another load of fixes, it went into atti mode.
I don’t know where you took off from, beach, car roof, or granite floor. There are so many variables as I say, without having the downloads from Airdata, it’s hard to say.
Worth reading the accident report on an occurrence with a Matrice 699 that shows similarities. You seem to have acted more quickly than the pilot and observer in the Matrice incident.
Investigating the cause will be beneficial, luckily you had the space to just emergency decend.
If you have the opportunity then fly some atti mode flights, in good weather and get to feel how the drone behaves. If you don’t lose the link then you can possible save your drone by manually flying the drone back in atti mode.
Hope your inspire is repairable and you get up ans flying soon.
Atti is a little uncomfortable but most of the time you won’t be flying intricate missions in atti, unless you are offshore.
Thanks alot for all the replies, I realise now the amount of variables involved. I took of from a fairly secluded beach, its the Danger area for live firing range where I work. It’s on the River Mersey which is a really busy shipping lane, there were 3 large vessels in the channel at the time if that is relevant?
I did not calabrate the compass prior to flying as I have flown here before and didn’t think it was required.
I am unable to link my drone to PC at present but will try through the week I did however record the flight data off the DJI go app if this helps.
If you haven’t already it is well worth linking to AirdataUAV which is free for 100 annual flights and subscription for more flights and features.
The free service is comprehensive enough flight map, second by second flight data, signal strengths and the like. You can set it in your flight app - DJI Go, Liychi or a dozen others to automatically upload the data at the end of each flight.
If you try it then decide that some of the more advanced features would be beneficial there is a discount code in the GADC members area
Just played your video full screen. Only four GPS satellites showing. Was that due to the interference or were there only four satellites received during flight?
If it helps, I’ve been able to force my Inspire in to ATTI mode (without hitting the switch) by simply flying it aggressively. Sharp turns, at speed, etc.
I’ve done this a few times now, it’s almost repeatable.
Here’s an output of one such flight - look familiar?
And if I replay your flight using the HD Player at around the 07m 01.2s mark you seem to do some very sudden moves with full left-stick inputs, right before it drops in to ATTI mode.
This may be nothing to worry about mate - just go easy?
