"But 3 fires is not mentioned."

This is interesting. I had always assumed that if I am in the wilderness and I desire rescue, then I should make three large piles of wood (assuming such fuel is available) and light it if a plane flies by overhead. At night they would (hopefully) see the three bonfires and during the day they would see the three columns of smoke. I had understood you should always augment the smoke with rubber, plastic, or anything else that would make it thicker and blacker.

Is this a wasted effort then? Obviously, if there are search planes out looking for you (as a result of a plane crash) then they are going to be looking for signals like this. But if you are a lost hiker, for example, will igniting three large piles of firewood simply be a waste of time?

I guess the question is this: if you (pilot, co-pilot, navigator, stewardess, or passenger) were to spot 3 fires at night, or 3 columns of smoke during the day, would you report it to anyone? And if you did, would anything be done about it?

Maybe PLB's are worth the money after all.

Regards, Vince