LIVE FOR CLASS on Instagram: "A rare piece of footage shows the exact moment the first plane hit the Twin Towers on September 11, 2001. The clip was filmed by French brothers Jules and Gédéon Naudet, who happened to be in New York documenting the lives of FDNY firefighters from Engine 7, Ladder 1. On what began as a routine call to check a suspected gas leak near the World Trade Center, they ended up recording one of the most defining moments in modern history."