The picture here is taken from the BBC. This depicts a tribe that lives on the border of Brazil and Peru and shows a tribe that has no contact with the outside world. Apparently there are about 100 known tribes in the world that have not been contacted. Since this is deep in the Amazon, it is unlikely that there will be contact, but the government of Brazil is keeping the territory free from logging and other developments that might affect their way of life.
The question that comes to my mind is this: Has the plane that flew over twice become a part of their mythology? How do they explain its existence? Is it a new monster or the form of an angry god? Seeing how they are shooting arrows at it, I doubt it would be conceived as a good thing. Unfortunately, I guess we will never know how this plays out.
There is a fairly decent Dirk Pitt novel called Inca Gold that starts with a similar event and shows how it was worked into the Inca mythology. All Dirk Pitt books are decent reads. This one is at least worth reading the first chapter (one day when you are in the library and bored).
You can read the BBC article on the tribe here: http://news.bbc.co.uk/2/hi/americas/7426794.stm