Historically, the navigation of a civil transport aircraft has been the responsibility of a specialist crew member. In the performance of his assigned task, the navigator has applied a complex set of mathematical and intuitive procedures by which he made navigational information useful. Now, because of increased accuracy requirements and of economic considerations, it is becoming apparent that the job of navigator must become an automated task.

An improved navigation system which meets present and future operational constraints does not lie in the development and implementation of more navigational sensors. While this approach may provide an equitable solution in the future, its present contribution would serve only to further burden crew members who are already functioning at or near their limit. Instead, the problem must be approached with the view of optimizing the tasks of a crew member who will ‘manage’ the navigation systems as a collateral duty.