An aviation expert told The Sun he believes several scenarios could be behind the deadly helicopter and plane collision - from a training mishap to a disastrous tech failure.
Training mishap, tech failure or human error: Tragic scenarios that may explain DC jet crash…& horrors passengers faced INVESTIGATORS are desperately searching for answers around the doomed Washington DC aircraft crash that is feared to have killed 67.
It was revealed after the collision that the packed plane was hit by a US Army Black Hawk helicopter as it was coming into land at Ronald Reagan National Airport.
The official reason is still a "mystery" with all the black box data from both the passenger plane and the Black Hawk military helicopter yet to be recovered and decoded.
Radio communications between the air traffic control tower and the Black Hawk show that the helicopter crew were aware that the twin-engine passenger plane was in the nearby vicinity.
