I did not see an established thread here or in current events... Germanwings Crash March 2015 For those not familiar, it's interesting that several/many, I don't know how many Eurpoean Airlines allowed a single pilot to remain in the flight deck during a pilot break, but in the U.S. as I recall right after 9-11, security policies changed and two crew members were always required up front, either an off duty pilot or a flight attendant. After all what if your single pilot has an event like a heart attack? I believe the single pilot policy will change in Europe now. It may also be of interest that an airplane like the Airbus A320 has flight laws that prevent the airplane from exceeding certain flight parameters , like nosing over the plane and exceeding a certain amount of pitch or overspeed, but the plane does not know if the intent is there to land or not so a controlled descent down is not surprising for this aircraft if the intent is to fly it into a mountain. And finally there was a day when airplanes had flight deck keys used to open the door, but now (at least in the Airbus), no key, but a code and that code can be overrided by the pilot to prevent entry to the flight deck, hence the need for two people up there at all times. If this had been the case, it would not have been impossible, but it would be much more difficult to pull off. To my knowledge, there have been no US based airline pilot suicides in this manner, but even so these kinds of event may end up with more routine pilot scrutiny being applied through some means. I understand depression, I don't hold it against someone who is depressed, I don't hold it against them if they think their life sucks and they want to end it. But I do hold it against them when they feel it's a justified to take a plane full of passengers with them, like "you deserve it too."