Investigators testifying at a hearing into the January's mid-air crash in Washington DC suggest faulty altitude data may have led to a miscalculation.

The helicopter was involved in a deadly crash with a passenger plane over Washington back in January.

Investigators testifying at a hearing into the January's mid-air crash in Washington DC suggest faulty altitude data may have led to a miscalculation.

Investigators conclude pilots of Black Hawk did not hear warning from air traffic controllers to pass behind jet

It’s too early for the board to identify what exactly caused the crash. A final report from the board won’t come until next year.