Greetings. I have a manual UAV target painter set up and one drone loaded with jet fuel, four napalm bombs from the mod and airstrip set up like this https://imgur.com/a/10ebJeL but drone still refuses to take off. What is the issue?

Hm... The airstrip looks good.
Can you rund the command "AircraftDronesDebug" in the console and tell me what it says, and maybe also post a screenshot of your hangar content?

It does not detect the commands of Aircraft Drones mod. Here is the hangar content https://imgur.com/a/67K85kn

It does not detect the commands of Aircraft Drones mod however. Here is the hangar content https://imgur.com/a/67K85kn

That looks correct. You can even see the number 1 in the targeter, that means there is one plane in range and ready to do missions.
Try placing a traget just next to the airport, what happens, does it just stay there?

The command just needs to be typed in the console, without the /c for normal commands. It's case sensitive, but I have never tried in in multiplayer.
You can also try rebuilding the hangar and runway manually, sometimes building it from bleuprints causes issues (especially with modded robots).

I built it all manually, targeting next to airport brought no result, command just doesn't exist.

Do you see the red mark on the ground? Maybe it's a multiplayer issue, the commands work in SP. Other mods which change the game forces or in general how artillery works are also not compatible.

Well, I use a few mods. Maybe Artillery Switch causes the issue.