calnan says there is an extensive checklist. ship workers have to go through when departing or arriving. >> some of the first things that go into it is voyage planning right, of course, we can't just leave the pier without knowing how we're going to get from a to b, and if an emergency happens, he says each worker on board has a job to do. >> we have to check to make sure that all of our gps receivers are working, that our radars are working, our ictus, which is our electronic chart, display and information, basically, our navigation system is working. >> he is now studying the baltimore crash to figure out what failed on the ship in san francisco. he says large ships are usually joined by pilots who help navigate the ship in and out of the bay. baltimore also has the same system. >> there's what's called a master pilot exchange of information, where that pilot, speaks with the captain of that vessel and is explained the handling characteristics, the propulsion plant of that vessel, any deficiencies, if they're known with any of