Over the summer (when we thought schools would be going back this Fall) we did multiple school solar module inspections. A perfect time to do it when there are not any cars or people on campus. And wow, we found multiple arrays with full strings out!
It really is amazing how solar module issues are so clearly visible via thermal/infrared inspection. Also, doing this manually would take almost the whole day and cost thousands of dollars… with a drone it was a fraction of the time/cost.