Here is a drone system that involves a large UAS carrying a smaller one and dropping it off to dig holes in the ground. One the job is done, the drone lifts and flies away. This video from NIMBUS Lab demonstrates how such a digging drone system works:
A highly modified S-1000 drone was used for this experiment. It parachutes down in a capsule and flies down to the area it needs to dig a hole.
[HT]