We are sorry to hear about this experience.
The drone stops when it runs short of battery and/or looses the connection. This depends on the settings defined in DJI GO for the Fail-safe option. Normally our app shows a pop-up when the battery reaches 20% and the remote controller emits a sound.
Size of the flight
Regarding the maximum area that can be covered in one single mission, the limiting factors are:
- Altitude and overlap (the higher the less overlap required, meaning fewer lines in the grid, and vice versa).
- Size of the grid (length of the flight track).
Actually the color of the grid refers to the estimated flight time that is calculated given the factors above assuming the battery is fully charged at the beginning of the mission. Note that it does not take into account the battery that is necessary to fly to the first way point of the grid and to come back. The color indicates a recommendation for flying safely with the app. However it is possible to bypass this limitation:
- In the Android app, it is possible to fly a yellow or orange mission if the advanced mode is activated (Home screen > Settings > section Advanced > check Enable advanced mode). The Android app is more optimized to fly large areas. You can find details about the best practice here: How to fly large areas: https://support.pix4d.com/hc/en-us/articles/211826243
- In the iOS app, even if the color is yellow or orange it is still possible to fly the mission.
Distance to the grid
The maximum distance from the center of the grid to the home point is set to 150 m on both Android and iOS. The home point is actually where the drone is turned on and acquired the GPS signal the first time. This distance is mainly for security reasons, to prevent an accidental launch of a mission when the grid is too far away and it is also limited to prevent connectivity losses. However, this can be discarded:
- Android: Activate the Advanced mode like above.
- iOS: Home screen > Grid / Double Grid / Circular Mission > Settings > tab Advanced > set the option Ignore home point to Yes.
Besides the home point distance limitation, there is also a safety lock that prevents the drone from starting if its current location is further than 250 m away from the center of the grid. The current location is either on the ground or in the air hovering (e.g. the drone starts a second mission right after the first without coming back to the user). To bypass this limitation, the user has to take off manually and fly the drone closer to the grid before tapping the green button to initiate the flight (in the takeoff checklist).
Hope this helps to better understand the situation.
Please let us know ho it goes next time.