Well the project has now been underway for >1.5 years so it is time to share it. You will find all the relevant video links and BOM in my GitHub repo for now as I move things over to a user-friendly format here on the Hackaday project. I've been testing the ESP8266 and YAGI antenna system for some time as well as the Nano Talon aircraft for remote use. So far it looks like this project works as I intended. 

It should be possible to detect a lots person in remote areas as long as their cell is turned on and wifi is not disabled. Commercial units are available using the cell signal "pings" but are limited to the exact frequency used by the phone (GSM LTE etc). They are also RIDICULOUSLY expensive >15K USD so no search and rescue or Game Warden organizations could likely ever afford them.  My version costs under $50 USD and can be used by people in the existing manned aircraft or attached to ANY drone or RC aircraft.  Handy.