testing. this is somebody a person who has 150 -- or sometimes more -- lives in their hands. do you believe that that has been a mistake? obviously it is a rare. thank goodness that's true. but it happened now. >> well dana it is interesting. the faa controllers who are faa employees, of course go through much more rigorous initial screening than is required of airline pilots in this country and they are periodically evaluated medically by faa doctors who are attuned to these kind of problems. so the system in this country is fairly loose because it frankly, hasn't been a large problem. your viewers should realize that the chances of dying at the hands of a demented airline pilot are certainly less than dying of an infected bee sting. so we don't want to overdo this but clearly we need to revisit this whole issue of voluntary