The aircraft was commanded outside of the geofence.

A user can use the Go-To Waypoint feature to command the aircraft towards a Go-To waypoint that is placed near (such that the loiter radius breaches the geofence) or outside of the geofence. 

Wind

Wind gusts may cause the aircraft to turn in the opposite direction than expected when making  a turn between passes over the survey area. If the turn is near the boundary the aircraft may violate the geofence. 

Mechanical failure

If the aircraft experiences a mechanical failure such as a broken linkage, the aircraft may continue to fly in a circle and get blown down wind. In this scenario it is possible that the aircraft could breach the geofence and trigger the failsafe. However, the aircraft likely won't return to land because it can not compensate for the compromised control surface.

Re-plan the mission and upload 

The pilot may choose to put the aircraft into a loiter by using the Pause/Hold flight mode. Then re-plan their mission to avoid any geofence violations and upload it to the aircraft. After that is completed the pilot may resume the mission. 

Continue the current mission 

Once the aircraft is back inside of the geofence the pilot may resume the mission instead of landing. 

Allow the aircraft to land 

The pilot may choose to let the aircraft land if they suspect there is a problem.

Emergency stop (**Mechanical Failure ONLY**)

In the case where there is a mechanical failure that is causing the aircraft to circle away, the pilot should maintain visual contact with the aircraft and use the Emergency Stop feature to shut down the aircraft propulsion system and allow the aircraft to circle to the ground.