it looks you have a well detected eth0 on the ground unit a least
I dont know what about the air unit but if you follow this Herelink Ethernet - #3 by Michael_Oborne
you should see also a eth0 on air unit
if you fix you pc and your payload IP in the 192.168.144.xx subnet you should be able to ping your payload from ground unit and you should be able to ping your payload from PC also that’s here I have an issue