Mavic Air flyaway (almost)

erlingm · Feb 13, 2018

Novice drone owner wondering if someone could look at my flightrecords and point out what went wrong, and/or if i did something wrong.

Flight records:
DJI Flight Log Viewer - PhantomHelp.com

capture of flight records witch shows the stick movement:

Checked sensors and imu before starting, with no issues. Starting point was about 50meters from a concrete bridge in a rural area and tempratures about 0 degrees. firmware was updated (no issues with shaking at takeoff as ive experienced before the newest firmware update) and go 4 was version 4.2.5.

The app didnt give any warning signs and cant find that the flightlog indicates any errors.

Climbed to about 20 meters and let the drone sit there for a few seconds (wanted to thinker with the image settings). Suddenly the drone took off going sideways. The youtube clip shows my stick inputs, and at around 16 seconds into the clip you can see im not doing any movements at the time the air sets off.

I should also mention that the drone, straight after takeoff moved abit from side to side (about 50cm), and settled down. I probably should have landed at that point...

Switched into sports mode (paniced abit, as you can see from the logg, switched sportsmode on and off 3 times) but i probably got controll over the drone at the first switch. Back into normal mode and landed.

shaunmichaelj · Feb 13, 2018

Yes. I had this issue two days after purchasing the drone.. it just took off.
I made a post, to which i received some feedback from some more experienced drone pilots who told me that i probably just panicked.

I have now flown a distance of 28,153 feet and I have had over 44 flights. (not sure if that counts for a lot, but i recently hit the sync button and went from level 0 to level 11).

After my firmware update yesterday.. I can guarantee I was not pushing the stick controls and the drone was hovering.. and it just took off... Fortunately I hit the pause button on the controls and it stopped. This is the same behaviour portrayed the first time it flew off, after i had only had it for two days.

The day before yesterday, I was filming a music video and a car drove past and the drone just disconnected from the controller and went up in the sky.. (the app was reporting the disconnection) fortunately it didn't go more than 6 feet and as i am tall I was able to grab it and turn it sideways. I was in the country side with VERY little interference.

Anyone have any ideas?!

sar104 · Feb 13, 2018

Was it windy? Looking at the pitch/roll/yaw data compared to the aircraft movements, it appears to have been initially trying to correct for wind:

At around 62 seconds it starts to roll right, holding position, but at 64 seconds, still with right roll, it accelerates to the left. That has to be a wind gust. That's then exacerbated when you reacted at 65 seconds with full left aileron causing it to roll left, although there is an odd 0.5 second delay in the response to the stick input (consistent throughout the flight).

erlingm · Feb 13, 2018

no wind that day to speak of (think weatherforecast was 2 meters per second...), and no gust at the time of the incident.

Think i have a video of the actual flight which i can upload if you`re interested, which shows the sea and how calm the weather was.

sar104 · Feb 13, 2018

erlingm said:
no wind that day to speak of (think weatherforecast was 2 meters per second...), and no gust at the time of the incident.

Think i have a video of the actual flight which i can upload if you`re interested, which shows the sea and how calm the weather was.

Well - you can see what the data show. If the motion described in the flight log is accurate (i.e. it flew off to the SW with the aircraft oriented facing NW) then there must have been a wind gust, since it cannot roll right and move left without that happening.

erlingm · Feb 13, 2018

sar104 said:
Well - you can see what the data show. If the motion described in the flight log is accurate (i.e. it flew off to the SW with the aircraft oriented facing NW) then there must have been a wind gust, since it cannot roll right and move left without that happening.

But for it to move that much in a short time it must have been a serious wind gust? Which i`ve should have taken note of? And my youtube clip correlates with the flight log which shows i had no input to the sticks when it started to move?

sar104 · Feb 13, 2018

erlingm said:
But for it to move that much in a short time it must have been a serious wind gust? Which i`ve should have taken note of? And my youtube clip correlates with the flight log which shows i had no input to the sticks when it started to move?

That's correct - initial movement was uncommanded. Your subsequent major stick input was left aileron a couple seconds later - that was in the wrong direction to arrest the motion. Can you confirm that when you took off the aircraft was pointing NW, as shown in your video in post #1?

erlingm · Feb 13, 2018

sar104 said:
That's correct - initial movement was uncommanded. Your subsequent major stick input was left aileron a couple seconds later - that was in the wrong direction to arrest the motion. Can you confirm that when you took off the aircraft was pointing NW, as shown in your video in post #1?

Yea it was facing NW, just doublechecked a normal map to make sure.

sar104 · Feb 13, 2018

erlingm said:
Yea it was facing NW, just doublechecked a normal map to make sure.

If you can get the DAT file from the aircraft that would be very useful, but it's been reported that there are problems getting those with recent firmware on the MP and possibly the MA.

dvarapala · Feb 13, 2018

erlingm said:
But for it to move that much in a short time it must have been a serious wind gust? Which i`ve should have taken note of?

Bear in mind that there can be winds aloft even if there is no wind at ground level.

erlingm · Feb 13, 2018

sar104 said:
If you can get the DAT file from the aircraft that would be very useful, but it's been reported that there are problems getting those with recent firmware on the MP and possibly the MA.

Ill try and grab it off the drone once i get home from work