I need some advice guys. But first here's what happened.
I was flying my Mavic Air2 this weekend on a predetermined loop that took it about 600 metres (2000 feet) from the home point at it's furthest extent. The plan was to fly low across fields and then to climb while looping back before descending to return to the homepoint. I had already made several flights without incident that afternoon and the battery had about 30% remaining. It was a straightforward, predetermined manoeuvre so I was confident there was plenty left to complete the flight. My first mistake.
All went well until I began the loop and climb. I first got a low battery warning and an RTH request. I cancelled this figuring I was looping back home anyway. Then, straight after hitting cancel, the DJI Fly app on my IphoneX froze completely! All data (speed, altitude, map, etc.) locked up and all the the onscreen controls became unusable. The live camera view did however remain on. This occurred at about the furthest extent of the loop so the aircraft was not visible (yes I know VLOS and all that - some folks might want to comment on this later...). I have no experience with this situation so I then spent the next 20 seconds (seemed like an hour!) at a loss what to do. According to the flight log, I did not alter the stick positions during this time so the aircraft continued climbing and looping back towards me, I assume therefore it was still receiving commands from the controller. It continued this trajectory until it reached its set ceiling of 120m (400ft), where it stopped (it looks like I released the sticks) and about ten seconds later issued an altitude warning which did appear on my otherwise frozen Iphone screen. This was followed by a second warning about altitude and authorization being required another 10 seconds after that. Still the app was not functioning and I was (probably mistakenly) assuming I was no longer able to control the aircraft. This is when I demonstrated the very common human inability to think straight in a stressful situation.
Super-stressed by the knowledge of a low battery, a frozen app and an invisible drone, according to the flight log I attempted to reduce the altitude by pulling backwards on the wrong stick! So the aircraft remained at maximum altitude but just flew backwards about 100metres.
The next message I received was a critical low battery warning and that the aircraft was landing automatically. This was to spell the beginning of the end of any further radio contact with the aircraft. A flurry of warnings then poured in over the next three and half minutes. At first repeated critical low battery warnings and then, as the aircraft descended behind a small nearby wooded hill and a ridge, additional random warnings about loss of signal and (oddly as, according to the log, it had a consistent link to 17 satellites) loss of GPS. So that was it. I thought my drone had vanished forever somewhere in the rolling Wiltshire downs.
I didn't mention that throughout much of this drama my son and I were jumping hedges and fences, crashing through cornfields and scrambling up ridges, running approximately in the direction of my precious drone's last known position. By now my son had the controller and had gone ahead. It seems also at some point the app had unfrozen because he was able to fire up the 'find my drone' function. It was this - despite no phone or 3 or 4g signal - that led him, zig-zagging methodically through knee-high corn, while bringing the two dots together, to a bare patch of soil and, sitting patiently in the middle, my exhausted, but entirely intact drone.
Needless to say I don't ever want to repeat that experience. I feel me and the drone got very lucky that day.
So with that in mind, can anyone give me some thoughts on why the app crashed, what I might have done or not done to have caused it and what I should do if it ever happens again?
I've noticed several people have had similar experiences with various app/phone combinations as well as the Smart Controller, but I've not really read a definitive fix, particularly when it occurs in mid-flight.
Also, am I right in thinking I still had full control of the drone through the sticks? Obviously, with no functioning display or VLOS, I couldn't know.
Comments and tips invited!
The Baron
I was flying my Mavic Air2 this weekend on a predetermined loop that took it about 600 metres (2000 feet) from the home point at it's furthest extent. The plan was to fly low across fields and then to climb while looping back before descending to return to the homepoint. I had already made several flights without incident that afternoon and the battery had about 30% remaining. It was a straightforward, predetermined manoeuvre so I was confident there was plenty left to complete the flight. My first mistake.
All went well until I began the loop and climb. I first got a low battery warning and an RTH request. I cancelled this figuring I was looping back home anyway. Then, straight after hitting cancel, the DJI Fly app on my IphoneX froze completely! All data (speed, altitude, map, etc.) locked up and all the the onscreen controls became unusable. The live camera view did however remain on. This occurred at about the furthest extent of the loop so the aircraft was not visible (yes I know VLOS and all that - some folks might want to comment on this later...). I have no experience with this situation so I then spent the next 20 seconds (seemed like an hour!) at a loss what to do. According to the flight log, I did not alter the stick positions during this time so the aircraft continued climbing and looping back towards me, I assume therefore it was still receiving commands from the controller. It continued this trajectory until it reached its set ceiling of 120m (400ft), where it stopped (it looks like I released the sticks) and about ten seconds later issued an altitude warning which did appear on my otherwise frozen Iphone screen. This was followed by a second warning about altitude and authorization being required another 10 seconds after that. Still the app was not functioning and I was (probably mistakenly) assuming I was no longer able to control the aircraft. This is when I demonstrated the very common human inability to think straight in a stressful situation.
Super-stressed by the knowledge of a low battery, a frozen app and an invisible drone, according to the flight log I attempted to reduce the altitude by pulling backwards on the wrong stick! So the aircraft remained at maximum altitude but just flew backwards about 100metres.
The next message I received was a critical low battery warning and that the aircraft was landing automatically. This was to spell the beginning of the end of any further radio contact with the aircraft. A flurry of warnings then poured in over the next three and half minutes. At first repeated critical low battery warnings and then, as the aircraft descended behind a small nearby wooded hill and a ridge, additional random warnings about loss of signal and (oddly as, according to the log, it had a consistent link to 17 satellites) loss of GPS. So that was it. I thought my drone had vanished forever somewhere in the rolling Wiltshire downs.
I didn't mention that throughout much of this drama my son and I were jumping hedges and fences, crashing through cornfields and scrambling up ridges, running approximately in the direction of my precious drone's last known position. By now my son had the controller and had gone ahead. It seems also at some point the app had unfrozen because he was able to fire up the 'find my drone' function. It was this - despite no phone or 3 or 4g signal - that led him, zig-zagging methodically through knee-high corn, while bringing the two dots together, to a bare patch of soil and, sitting patiently in the middle, my exhausted, but entirely intact drone.
Needless to say I don't ever want to repeat that experience. I feel me and the drone got very lucky that day.
So with that in mind, can anyone give me some thoughts on why the app crashed, what I might have done or not done to have caused it and what I should do if it ever happens again?
I've noticed several people have had similar experiences with various app/phone combinations as well as the Smart Controller, but I've not really read a definitive fix, particularly when it occurs in mid-flight.
Also, am I right in thinking I still had full control of the drone through the sticks? Obviously, with no functioning display or VLOS, I couldn't know.
Comments and tips invited!
The Baron
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