‘Incapacitated’
“You can’t rule out the possibility at this point of the pilot who was remaining in the cockpit becoming incapacitated simultaneous with when the other pilot walked out,” he said. “It’s more likely that the pilot may have done something intentionally, but you can’t conclude that until the flight data recorder is recovered.”
http://www.bloomberg.com/news/articles/2015-03-26/germanwings-crash-probe-focuses-on-pilots-as-recorders-evaluated
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I agree with the above remarks. Some things don't add up, despite the apparent deliberate actions. He was too calm. They could hear him breathing normally on the voice recorder, from some of the four cockpit microphones. He didn't taunt anyone, mumble anything, or just point the airplane straight down, or simply shut off the two engines. Instead he did it in such a way as to keep the passengers calm until just before the end, when they realized from the Captain's reaction just outside the door that they were doomed. Not manic, too deliberate for someone that had to have been deeply disturbed to commit such a horrific act.
Auto Pilot was MANUALLY adjusted after the pilot was locked out according to those who monitor such things.