The Army helicopter that collided with a plane over D.C. in January had incorrect altitude readings, contributing to the aircraft getting too close.

The National Transportation Safety Board enters a second day of public hearings Thursday on the January midair collision between an Army Black Hawk helicopter and a passenger plane that killed all 67 people aboard the aircrafts.

The NTSB is holding three days of hearings to uncover insights into what caused the fatal crash between the passenger jet and the army helicopter over Ronald Reagan National Airport in January.