The National Transportation Safety Board questioned witnesses Friday on collision avoidance technology and organizational systems to manage risk. It is the third and final day of investigative hearings probing January’s midair collision between a US Army Black Hawk helicopter and an American Airlines regional jet,

Investigators so far have highlighted several factors that may have contributed to the collision, which left 67 people dead.

Investigators so far have highlighted several factors that may have contributed to the collision, which left 67 people dead.

Although the D.C. Council cleared the RFK Stadium deal in its first vote, the advancement showed several members had to be convinced to do so.