The validity of the " see and avoid " doctrine as a safe means of aircraft navigation was a point of contention between the NTSB and the Federal Aviation Administration ( FAA ) . The NTSB had faulted the doctrine in several earlier collisions , including the 1969 collision of Allegheny Airlines Flight 853 with a privately owned Piper PA-28 and the 1967 collision of Piedmont Airlines Flight 22 with a privately owned Cessna 310 . The FAA rebutted these findings and insisted that , regardless of the mode of operation , it is the duty of the aircraft pilot to be aware of any aircraft in his immediate vicinity
Allegheny Airlines Flight 853
Allegheny Airlines Flight 853
Hughes Airwest Flight 706