Air 2S darting forward and crashing into a roof twice!

[JohnySVK]

I had my first emergency crash landing with my Air 2S today. I was taking pictures of a log cabin in a forest with trees all over, so I had to disable the obstacle avoidance to get closer to the trees. As I was inching forward between a branch and the roof, the drone just took off forward and I heard it hit the roof. I managed to get it back in the air somehow and it seemed to be alright, although pulling a bit to the side. I started to bring it home, but the second it got close to the roof it just took off again and did the same thing. I heard it hit the roof and at that point I've decided to force land it behind the cabin on a sloped forest floor. It wasn't the softest landing, and some weed's got chopped off and stuck behind the gimbal but given the drone's erratic behavior I was glad it's down. My question is: what could've cause it to suddenly take off like that? I was about 1 foot off the roof when it happened in both cases. I've heard about people losing drones when flying close to the water, but this didn't make sense. Any advice is appreciated.

 

[Meta4]

My question is: what could've cause it to suddenly take off like that?

The answer to questions like that are always the same.
Post your recorded flight data and it might help find out what happened.
There are a couple of options ...

1. Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a detailed report on the flight data.
Come back and post a link to the report it provides and someone might be able to analyse it and give you an understanding of the cause of the incident.
or
2. Just post the .txt file here
or
3. If you use Airdata, you can view the flight data on Airdata and post a link for the Airdata report

I've heard about people losing drones when flying close to the water, but this didn't make sense. Any advice is appreciated.

Flying close to water doesn't cause erratic behaviour.

 

[JohnySVK]

The answer to questions like that are always the same.
Post your recorded flight data and it might help find out what happened.
There are a couple of options ...

1. Go to DJI Flight Log Viewer | Phantom Help
Follow the instructions there to upload your flight record from your phone or tablet.
That will give you a detailed report on the flight data.
Come back and post a link to the report it provides and someone might be able to analyse it and give you an understanding of the cause of the incident.
or
2. Just post the .txt file here
or
3. If you use Airdata, you can view the flight data on Airdata and post a link for the Airdata report


Flying close to water doesn't cause erratic behaviour.

Thank you for the instructions, it took a bit of searching but I found it. I've never done this before.

Here's the link to my flight log

DJI Flight Log Viewer | Phantom Help

Upload and view flight logs from your DJI drones

www.phantomhelp.com

The first incident occurred at 4:03.5

The second incident occurred at 4:30.0

 

[Meta4]

I had to disable the obstacle avoidance to get closer to the trees.

First up, the recorded data shows that obstacle avoidance was enabled.

As I was inching forward between a branch and the roof, the drone just took off forward and I heard it hit the roof. ... My question is: what could've cause it to suddenly take off like that? I was about 1 foot off the roof when it happened in both cases.

You were using Sport Mode which is odd if you were flying close to obstacles and needing gentle control ??

It's a little tricky to work out what was going on because you were using a non-standard joystick format, which means my brain has trouble working out what your joystick inputs were..
I can see the two crashes happening at 4:04.4 and 4:31.5.

I note that immediately before each crash, you pushed a joystick fully forward and if I've worked out your joystick assignment correctly, it was the stick that moves the drone forwards.
Pushing the stick fully forwards in Sport Mode when close to obstacles is very risky.

It looks to me that that was the reason for the drone darting forwards.

 

[JohnySVK]

First up, the recorded data shows that obstacle avoidance was enabled.


You were using Sport Mode which is odd if you were flying close to obstacles and needing gentle control ??

I was under the impression the sports mode turns off obstacle avoidance. I don't know how else to turn it off directly from the controller.

It's a little tricky to work out what was going on because you were using a non-standard joystick format, which means my brain has trouble working out what your joystick inputs were..
I can see the two crashes happening at 4:04.4 and 4:31.5.

Yeah I'm sorry, I was trying for a couple of months to get used to the standard format, but it just wasn't working. I think it's because of all the games I used to play as a kid where the left hand was always forward lol

I note that immediately before each crash, you pushed a joystick fully forward and if I've worked out your joystick assignment correctly, it was the stick that moves the drone forwards.
Pushing the stick fully forwards in Sport Mode when close to obstacles is very risky.

It looks to me that that was the reason for the drone darting forwards.

I can assure you I did not push the joystick fully forward. Definitely not twice in a row. I was inches away from tree branches and roof inching forward in each direction to get past the obstacles. At certain point the drone just took off on it's own. Twice.

 

[old man mavic]

@JohnySVK i dont have a Air 2s but its my belief that the OA works in a similar fashion to my Mini 3 pro which is bypass stop or off ,and these settings can be set in the menu on the device screen ,if you had done this you could have flown in cine mode for more control and gentler movements

 

[Phantomrain.org]

Im wondering if at some point your home point was changed during the flight, this would explain why it took off on it own. Did you at any time get a second home Point recorded as that might explain the drone taking off.

Phantomrrain.org
Gear to fly in the Rain. Land on the Water

 

[Meta4]

Im wondering if at some point your home point was changed during the flight, this would explain why it took off on it own. Did you at any time get a second home Point recorded as that might explain the drone taking off.

No ... the recorded home point stayed the same from beginning to end, just as they always do.
And if the home point is changed, that doesn't cause a drone to fly off or move erratically.
Normal flight continues and the drone would fly to the new home point if RTH was initiated, but not until then.

 

[Meta4]

I was under the impression the sports mode turns off obstacle avoidance.

Sport Mode is the last thing you want when flying close to obstacles.
You have lost OA and the drone accelerates faster.

I don't know how else to turn it off directly from the controller.

Here is how you disable OA in the app settings

I can assure you I did not push the joystick fully forward. Definitely not twice in a row. I was inches away from tree branches and roof inching forward in each direction to get past the obstacles. At certain point the drone just took off on it's own. Twice.

The data is not on your side.

First crash
Yellow - You changed from Normal (P-GPS) Mode (with OA) to Sport
Blue - Horizontal Speed
Pink - Pushing left stick forward, speed increases
Red - Left stick fully forward, speed increases more
Purple - Crash, drone tips forward and rolls over briefly

Second crash is similar

 

[mobilehomer]

Also, depending upon how your Gain and Expo are set, just a little input can give full input.

 

[rickmurray1989]

One foot from the roof is awfully close. Perhaps prop wash came into play, creating vortices that forced it into the roof?

 

[Meta4]

One foot from the roof is awfully close. Perhaps prop wash came into play, creating vortices that forced it into the roof?

See post #9
No mysterious vortices forcing the drone forward.

 

[JohnySVK]

Sport Mode is the last thing you want when flying close to obstacles.
You have lost OA and the drone accelerates faster.

Here is how you disable OA in the app settings

Thank you. As I said in the previous post, I was under the impression that switching to sport mode does the same thing as turning the OA off. I now understand that in not only turns it off, but makes the controls more responsive. I'll keep that in mind for the future flights.

The data is not on your side.

First crash
Yellow - You changed from Normal (P-GPS) Mode (with OA) to Sport
Blue - Horizontal Speed
Pink - Pushing left stick forward, speed increases
Red - Left stick fully forward, speed increases more
Purple - Crash, drone tips forward and rolls over briefly

Second crash is similar

Thank you for the breakdown. I wouldn't call myself an experienced pilot yet as I only have some 170 flights equaling to about 16 hour of flight time, but I can't stress enough that I did not push the controller full forward. If there was some slimmer of doubt after the first crash, it was completely eradicated after the second. I was very much aware of what I'm doing and the idea of going full forward would never cross my mind in this scenario. I don't understand the inner workings of drone/controller connection and I can see the left stick going full forward on the flight log, but I can assure you that command did not come from me.

 

[Phantomrain.org]

Just curious where you think the home point recorded itself ? Was it on the ground or in the Air ?

Phantomrain.org
Gear to fly in the Rain. Land on the Water

 

[Meta4]

Just curious where you think the home point recorded itself ? Was it on the ground or in the Air ?

Where it was recorded is completely irrelevant to the alleged incident.
Whether it was recorded on the ground, in the air or a mile away wouldn't make any difference or change the way the drone behaved.

Also, homepoints have no height associated with them.
They are just a lat and long.

As it happens, the drone was launched and flown a short distance from the launch point before the homepoint was recorded with the drone approx 40 feet up.

 

[Phantomrain.org]

Obviously it was , but I watned the OP to tell me where he thought the Home Pont was recorded but thanks for the Confirmation as i was surprised that it was not Mentioned.

Yes the Home point was recorded 40 FT Up , i find this very interesting regardless of the incident.

Hopefully I will get a answer from the OP

Phantomrain.org
Gear to fly in the Rain. Capture the Storm and wait for the Home point.

 

[Meta4]

Yes the Home point was recorded 40 FT Up , i find this very interesting regardless of the incident.

It's not particularly interesting.
It's a common thing in the flight data and I see it quite often.
But it would only ever make any difference if RTH is initiated and the drone would return to where the home point was recorded and descend until it reaches the ground, regardless of how high the drone was when the home point was recorded

 

[JohnySVK]

Just curious where you think the home point recorded itself ? Was it on the ground or in the Air ?

Phantomrain.org
Gear to fly in the Rain. Land on the Water

I took off from the roof of my car some 100 feet away as the road was on a slope and this was the most level option. I didn't notice home point being updated during flight.

 

[RodPad]

I took off from the roof of my car some 100 feet away as the road was on a slope and this was the most level option. I didn't notice home point being updated during flight.

Roof of your car?

Rod ..

 

[JohnySVK]

Roof of your car?

Rod ..

Yes, just as I usually do. I've never had any issues. It's usually cleanest place around for take-off.