I wonder if analog dosimeters might be a better way to narrow down the search area more cheaply and quicker to set-up. Fly or drive a run. Check dosimeter.

Dunno if there's enough energy expected to set it off at the expected speeds travelled. Obviously they don't go "ding ding ding". Might find some spurious beta-radiation sources?

https://www.uth.edu/safety/radiation-safety/personal-radiati...