The hearings in Washington will involve NTSB board members, investigators and witnesses. Panels will focus on military helicopter routes in the Washington area, collision avoidance technology and training for air traffic controllers at Ronald Reagan National Airport, among other subjects.

In May, the FAA barred the Army from helicopter flights around the Pentagon after a May 1 close call that forced two civilian planes to abort landings. The FAA this week said the

The pilots of a Black Hawk helicopter that collided with a passenger jet near Washington Reagan National Airport in January never heard an air traffic controller's instruction to pass behind the jet,