Air traffic control managers told the National Transportation Safety Board that F.A.A. leaders rebuffed efforts over the years to address hazardous conditions that played a role in the Jan. 29 crash.

Air traffic controller failed to notify commercial plane crew about approaching Army helicopter before Washington D.C. collision that killed 67 people, FAA official says.

The acknowledgement came during the second day of testimony held to discuss the collision of a commercial plane and Army helicopter in January that killed 67 people.