Magic Air takes off by itself and flies at me!

[Jaws369]

New one for me today. Took my MA on a boat to take some awesome video stripper fishing and after turn on, it asked for a calibration Which I did on the bow. Then I started the motors and left it idling to show my friends the screen. After about 3 to 5 seconds, not touching the sticks, it spun to full power and flew up and directly in my direction. Hit my leg and hand. Nice gash cut into leg.
So is it IMU, Compass or joystick? Anyone else have this happen?
How do I tell now that i’m home?
Thanks.

 

[InvisibleName]

New one for me today. Took my MA on a boat to take some awesome video stripper fishing and after turn on, it asked for a calibration Which I did on the bow. Then I started the motors and left it idling to show my friends the screen. After about 3 to 5 seconds, not touching the sticks, it spun to full power and flew up and directly in my direction. Hit my leg and hand. Nice gash cut into leg.
So is it IMU, Compass or joystick? Anyone else have this happen?
How do I tell now that i’m home?
Thanks.

Post your flight file and ask someone to have a look. Without, it sounds like you moved the stick without realising!

 

[Jaws369]

I’ll see how to do that and post it. However I did it a second time and it repeated it, but this time I grabbed it before it went away.

 

[InvisibleName]

I’ll see how to do that and post it. However I did it a second time and it repeated it, but this time I grabbed it before it went away.

You mean you started the rotors turning & then it took off without any further stick input? That’s scary!

 

[Mossiback]

Was the boat moving? Were there big waves?

 

[InvisibleName]

You find the instructions at airdata.com then post the web link they will give to you here.

 

[Jaws369]

Yes - the boat was moving up and down in the waves. Is there something in the firmware that if the rotors are spinning, the rig will take off? I should be able to drop it and it just hits the ground rather than an unsolicited take off.

Why is it so difficult to upload a log file without having to make multiple accounts at different sites? That seems quite strange.

 

[Simmo]

There was a thread some time back where a Mavic did a very similar thing. @sar104 analysed the .DAT file and found that the movement of the boat caused the drone to attempt to hold altitude by taking off.

 

[Don H.]

Did you get a shot of the Stripper? With or without the Stripper pole?

Sorry,,couldn't resist.

 

[Jaws369]

There was a thread some time back where a Mavic did a very similar thing. @sar104 analysed the .DAT file and found that the movement of the boat caused the drone to attempt to hold altitude by taking off.

Wow - that is crazy if true. I never gave it permission to takeoff.

 

[Simmo]

Mavic Pro took-off without given command and crashed :(

 

[Jaws369]

Wow - Ok from an engineer POV, if I have not given permission to T/O, it should NEVER T/O. Plain and simple. Sloppy programming. What I read at least explains it, but I still ended up with a cut up leg from my Mavic Air due to shoddy programming no matter how it's looked at. I have never made a program or control system that energizes and runs without the "run" button. Just because it's idling, does not satisfy all interlocks.
WTF DJI? This should be fixed for all people.

SIMMO - Thanks for the link and the knowledge. That was incredibly helpful. I'll just have to be more careful next time and hand launch my drone and recapture in the swells.

 

[Jaws369]

Did you get a shot of the Stripper? With or without the Stripper pole?

Sorry,,couldn't resist.

No Stripper shots unfortunately - but did get quite a few of the stripers! LOL

 

[RayOZ]

Why would you start the motors when you aren't ready to take off? Once motors are spinning, I think the control system is active. So it'll try to hold altitude. When the boat goes up and then down, expect control system to act on it.

 

[msinger]

If you post your log, please upload it here (instead of at Airdata) and post a link to the uploaded log here.

 

[Mossiback]

I plan on flying in a couple hours and normally hand launch. I will see what happens when I have it at idle and lower it by hand.

 

[sar104]

Wow - Ok from an engineer POV, if I have not given permission to T/O, it should NEVER T/O. Plain and simple. Sloppy programming. What I read at least explains it, but I still ended up with a cut up leg from my Mavic Air due to shoddy programming no matter how it's looked at. I have never made a program or control system that energizes and runs without the "run" button. Just because it's idling, does not satisfy all interlocks.
WTF DJI? This should be fixed for all people.

SIMMO - Thanks for the link and the knowledge. That was incredibly helpful. I'll just have to be more careful next time and hand launch my drone and recapture in the swells.

In that previous thread I came to the conclusion that the behavior may be related to the ability to launch the aircraft by throwing it into the air. Not that I've tried it for real, but when I tested it with no props installed it did spool up and attempt to fly when dropped.

 

[Jaws369]

Why would you start the motors when you aren't ready to take off? Once motors are spinning, I think the control system is active. So it'll try to hold altitude. When the boat goes up and then down, expect control system to act on it.

Sorry but this makes no sense. Do you think an plane, helicopter, car, motorcycle, lawnmower cannot idle without the system thinking it's running/flying? This is an interlock. I should be able to let me MA sit, idling for 15 minutes, looking out the camera, letting it do what it wants, programming in a flight, reading how to use a new feature, etc, all without it taking off and flying into something. Not good control programming at all.

 

[Simmo]

It will do what you say mate, on terra firma!. The movement up and down is 'fixed' by the FC and sensors. Thats why when youve flown it, I bet people have commented, "OMG look how stable it is"......

 

[ac0j]

Most people hand launch from a boat. but it is the up and down movement that screwed you, as would trying to launch the mavic while the boat was moving forward