Dennis Diaz carries a number of items with him in his "Go Bag" in case of a plane crash.
The National Transportation Safety Board investigates why plane crashes happen, so it can prevent them from happening again. NTSB investigators are on call for weeks at a time, ready to head to a crash site to perform intricate mechanical autopsies. David Schultz meets some NTSB investigators in Northern Virginia, to find out what makes them tick.
[Music: "A to B" by The Futureheads from The Futureheads / "In the Air Tonight" by Takka Takka from Guilt By Association, Vol. 2]