Built scaled up replicas of gold trinkets recovered from tombs, put propellers on them, and successfully flew them.
" At the August, 1997 meeting of the " Ancient Astronaut Society World Conference," gathered in Orlando, Florida, the two researchers presented their independent findings on the "insects." Those assembled literally cheered when Belting's model (powered by a small jet engine - left) flew a set of complex aerodynamic maneuvers … and then came in for a perfect landing - all with a model airplane built as an exact match to a tiny gold trinket found in an Incan grave … dated minimally to over a thousand years ago!"
It's quite healthy to get one of these googly's now and again :) Just imagine the far more logical and practical approach that would have been followed to properly test this stuff out if the mainstream stopped resorting to all the "conspiracy theory" branding and dismissing and instead just took things logically and allowed people to explore. Instead, no, we have to brand this and dismiss it and ridicule the people interested in it and so cut out any possibility of actually testing and proving or disproving.