The National Transportation Safety Board has determined that the probable cause of a midair collision between two emergency medical service helicopters last year was that both pilots failed to see and avoid the other helicopter on approach to the helipad.
actual report from flagstaff crash:
The National Transportation Safety Board has determined that the probable cause of a midair collision between two emergency medical service helicopters last year was that both pilots failed to see and avoid the other helicopter on approach to the helipad.