certifying the health and mental well-being of their pilots? >> well alex when a candidate shows up for employment with the airline as a pilot, you go through a whole bat of tests, academic, practical, and medical and psychological. so there's a pretty good indication of how well this individual will fit into the airline. and as they go through training they are carefully evaluated by instructor pilots and pilots that they fly with. once they're qualified and they're flying what ends up happening for the most part is what's known as a peer review. that is pilots work very closely with each other. you're on the road you're traveling together you're working in close physical proximity to each other. and if someone is not meeting the standard or seems preoccupied, it is not uncommon that one of the pilots will ask the other, are you doing okay?