Experts decode what could have caused Army chopper-plane crash in US

A passenger jet collided with a military helicopter near Washington DC, crashing into the Potomac River. The American Airlines flight was approaching Reagan National Airport when it hit a US Army Black Hawk. At least 19 bodies have been recovered, with 48 still missing. The incident raises questions about air traffic control and collision avoidance systems in one of the world's most regulated airspaces. So, watch as veteran pilots and aviation experts decode what could have caused an Army chopper-plane crash in the US.