I have some STOL UAV plans from an old school FAC that had some published articles on UAV concepts a while back. They kind of address what Xenophon is saying though they are longer range in concept. I'll have to see if the owner of the concepts is okay with me sharing. There was a double ducted fan VTOL UAV design a few years back by the same company that was trying to make backpack vtol that was meant for resupply type missions. My though is that they would have to be able opperate autonomously to be viable.
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