>> it's absolutely possible. most psychological evaluations are simply a checklist. and a person will answer and the evaluator will look down to mark it on his paper, never looking to see what kind of body language, maybe the person withdraws or does something that gives you a clue that there's some sort of stress or anxiety in answering the question. >> reporter: another problem, pilots say the airlines don't check periodically to see if someone has come up in a pilot's personal life that may lead to a psychological breakdown, like a marital or financial issue. and they're not required to check for that. it's up to a pilot to self-report. if he or she doesn't self-report, what happens? >> if you don't self-report, it's really gone unnoticed. typically what happens is, if you have an issue, one of your crew members might recognize something like that. >> reporter: the faa did not respond to our questions about the criticism of that system. some current and former pilots argue the rules don't need to be tightened.