Several days ago a prop was not locked in place properly by an employee on the Matrice 100, on auto take-off it got to the 3 - 3.2 ft height and the propeller spun off, the Matrice immediately turned itself upside down and augered into the dirt. We shut down the motors as the loss of control occured and a post impact inspection did not show any outward damage and DJI-Go app does not report any warnings or alerts however, a test flight today resulted in a loss of stability immediately on take-off with only altitude stick input. At 2 ft the airframe wobbled and rolled itself onto its side and into the ground.

I have several questions:

1.) is there additional data recorded in the DJI Go App (Error reporting / extraneous signals / motor flucuations etc. etc.) that can help me determine what damage has been done or calibration has been thrown out of whack.

2.) I cant keep powering the thing up and hoping and praying whatever was done is fixed, when there is a flight problem that only actualy "flight" can determine if its fixed, how do any of you prevent these roll-overs or other wild behavior that results in impacts? My only thoughts so far would be to tie the four legs of the matrice to 4 equal corners so it can hover but not roll over. Any other testing ideas?

3.) I'm tempted to send the unit to DJI for diagnostic and repair, however - i have a legitimate concern that repair costs can be significantly close to the cost of the units themselves (Labor rate i guess) has anybody had a significant imact event and sent there units back under DJI after care program? What was your experience with that and cost?

4.) Lastly, since i dont see any kind of "diagnostic" mode in the app and the aircraft thinks its ok - anybody have a standardized checklist of what they check or do after an impact before trying to fly the units again?

Several days ago a prop was not locked in place properly by an employee on the Matrice 100, on auto take-off it got to the 3 - 3.2 ft height and the propeller spun off, the Matrice immediately turned itself upside down and augered into the dirt. We shut down the motors as the loss of control occured and a post impact inspection did not show any outward damage and DJI-Go app does not report any warnings or alerts however, a test flight today resulted in a loss of stability immediately on take-off with only altitude stick input. At 2 ft the airframe wobbled and rolled itself onto its side and into the ground.

I have several questions:

1.) is there additional data recorded in the DJI Go App (Error reporting / extraneous signals / motor flucuations etc. etc.) that can help me determine what damage has been done or calibration has been thrown out of whack.

2.) I cant keep powering the thing up and hoping and praying whatever was done is fixed, when there is a flight problem that only actualy "flight" can determine if its fixed, how do any of you prevent these roll-overs or other wild behavior that results in impacts? My only thoughts so far would be to tie the four legs of the matrice to 4 equal corners so it can hover but not roll over. Any other testing ideas?

3.) I'm tempted to send the unit to DJI for diagnostic and repair, however - i have a legitimate concern that repair costs can be significantly close to the cost of the units themselves (Labor rate i guess) has anybody had a significant imact event and sent there units back under DJI after care program? What was your experience with that and cost?

4.) Lastly, since i dont see any kind of "diagnostic" mode in the app and the aircraft thinks its ok - anybody have a standardized checklist of what they check or do after an impact before trying to fly the units again?