look like anyone could have survived. >> reporter: you look over there what do you see? >> i see twisted metal. looks like some sort of significant trauma happened to that wing. crashed into something. hit something. i don't know. pole. >> reporter: we teach the discipline of accident investigation, namely to observe the fact, to document the fact and then let the facts take you by the hand and lead to you the next fact. and the discipline not to conclude, not to summarize and not to think too far ahead. stick with facts. minutes later i jumped to a faulty conclusion looking at different wreckage. it almost looks like a crumpled beer can. what we see here is the power of a thunderstorm. if we can teach one thing it is never one thing. it's always a chain of interrelated causes.