FLY AWAY FOUND IN PERFECT CONDITION

Meta4 · Mar 22, 2021

rewizard said:
Attached please find.dat file.

The .txt file is what was asked for.
Can you post that please?

rewizard · Mar 22, 2021

Attached is the TXT file

slup · Mar 22, 2021

The AC is according to the log a Mini 2 flown with a DJI FLY app version 1.3.1 ... meaning Airdata is the only thing we have to decrypt the .TXT log & the mobile device .DAT log is unreadable due to that it's encrypted.

So NOT much to go on here I'm afraid ...

This is seen in the last messages in the log at Airdata though ...

So one scenario could have been that it actually drifted away & the pilot didn't know how to handle ATTI mode ... & didn't know that with ATTI comes no horizontal positional hold at all & no breaking when releasing the sticks.

Meta4 · Mar 22, 2021

rewizard said:
Attached is the TXT file

That flight only lasted 43 seconds before the drone bumped into something, fell and lended upside down.
The height never exceeded 11 feet and speed was very slow and touched 12 mph just as the drone crashed.

In your first post you mentioned flying to 250 feet so I'm not sure this data relates that that flight???
There was very little throttle input in the data so the altitude data appears believable.

The number of satellites acquired was no more than 7 so no homepoint, location or distance data or horizontal position holding.
Was the flight out in the open where the GPS receiver had a clear view of most of the sky or was a building, tree cover etc blocking the sky view?

rewizard · Mar 22, 2021

Was blocked (covered) I am very grateful for you interpretation as I could not gleem anything from the file. Thanks. It is apparent to me that I never got a GPS established and as the drone stated to fly away I did not realize or expect it to be in ATTI mode. I apparently just lost control and was lucky to get it back. The reason it is showing 11 feet is that I took off from approximately 160 feet. So I was more or less at 172 feet when it crashed into the 24th floor balcony. I have flown from the same site many times and always re establish home point immediately. This flight I waited too long. Thanks for all your input.

slup · Mar 22, 2021

Meta4 said:
...The height never exceeded 11 feet

In your first post you mentioned flying to 250 feet so I'm not sure this data relates that that flight???

According to the cached photos in the log the flight most likely started here ...

And this height is probably what's mentioned ...

rewizard said:
... I did not realize or expect it to be in ATTI mode. I apparently just lost control and was lucky to get it back.

Yep, that's what likely happened.

Meta4 · Mar 22, 2021

rewizard said:
as the drone stated to fly away I did not realize or expect it to be in ATTI mode

The drone didn't fly away.
It just didn't have the ability to hold horizontal position and had no brakes.
It was still fully controllable but atti mode confused you because the drone wasn't behaving as you expected.
Atti mode is like driving on ice because when you go hands off, the drone keeps drifting.
Out in the open, that's no problem but close to obstacles you have to be very careful and use very gentle joystick inputs.

rewizard · Mar 23, 2021

THANKS to all of you for your input.

rewizard · Mar 23, 2021

I suppose if I had FPV experience this would not have happened. I remember I was stunned and tried moving the sticks aggressively. I intend to practice ATTI mode flying today, just in case. However, quickly setting a home point always worked. One lapse of thought and bye bye. That will not happen again.

rewizard · Mar 23, 2021

slup said:
According to the cached photos in the log the flight most likely started here ...

View attachment 126119

And this height is probably what's mentioned ...

View attachment 126120

Yep, that's what likely happened.

That is exactly correct. The flight originated on the 24th floor balcony ( I would assume 10'/ floor so approximately 240 ft. I have made a large number of flights from here always flying over the tennis court to set home point. I live near the Ocean and is usually my destination. I think I got distracted and never got to set home point and away she went in ATTI mode. I did not respond accordingly and it crashed ( no damage other than props scuffed) on the corner balcony. AS mentioned before, it was returned by the Realtor who has the listing. Lesson learned.

slup · Mar 23, 2021

rewizard said:
...The flight originated on the 24th floor balcony...

Having ATTI mode in the initial part of the flight isn't the only risk you are taking with that launch location ...

That balcony is for sure made of steel reinforced concrete & surrounded by other magnetic objects ... all this means that you risk a deflected compass during the power on moment making the IMU getting wrongly initialized. That will lead to a yaw error ... simply put, the IMU don't know in which direction the drone is pointing.

A yaw error due to a magnetically deflected compass during power on will later in the flight lead to this in the video...

The drone in the video is actually trying to hold position and fight the winds that are affecting it ... but as the IMU in that drone don't know in which direction it points it does it by commanding the wrong motors ... & just making the positional error larger ... & it flies away with full speed.