A morning call for a possible gas leak was the last normal thing FDNY Chief Joseph Pfeifer experienced on Sept. 11, 2001.  "We heard a loud noise of a plane coming overhead, and we saw this plane racing down the Hudson River, so low I could read the American Airlines on the side," said Pfeifer. After that, the day went from routine to tragic. "I saw the plane aim and crash into the North Tower of the World Trade Center and in that moment, I knew this was not an accident, but a deliberate attack," he said. Pfeifer was the first fire chief to respond to the World Trade Center. With him was a film crew, working on a documentary about a rookie firefighter. Instead, it ended up capturing some of the most dramatic moments of 9/11. "One [memory] is my firefighters coming into the building...They came in quiet, and said 'Chief, what do you need?'" said Pfeifer. "One of those fire officers was my brother, Kevin, from Engine 33. And I told him as I told many other officers, I said 'Go up, evacua...