Humble Pax here, sorry if this post has no place here, I do respect leaving it to the experts on here generally. However, I am absolutely flabbergasted that my phone and tablet can be tracked by GPS if they go astray, but according to an article on the BBC planes cannot, and black boxes cannot. Sorry if I have misunderstood and mods of course please delete if this is an unhelpful/useless post.
BBC article