Abstract: ACKNOWLEDGMENTS This thesis work was performed under a wide variety of circumstances, and with the assistance of many people. Most outstanding among these are my advisor, Professor Walter M. Hollister, without whose constructive criticisms , positive encouragement and wisdom this thesis would not have been accomplished; Mr. Anthony E. Scandora, who supplied invaluable technical help; and Mr. Peter V. Hwoschinsky, whose work on closely related topics gave us many opportunities to work together. Many other people provided cooperation, time, hardware, assistance, ideas, and inspriration. I was fortunate to work with many fine and worthwhile people, whose omission by name here in no way reflects my lack of gratitude. who introduced me to the concept of graduate education as a uniquely wonderful opportunity. The second appendix of this thesis was written for another report under NASA Contract NAS1-13644, coauthored by Hwoschinsky and others. Thus, the text of the appendix reflects the editing of various people. Similarly, the data base on which the analysis of Chapter VI is based was performed under that same contract.

Abstract: A two-segment noise abatement approach procedure for use on DC-8-61 aircraft in air carrier service was developed and evaluated. The approach profile and procedures were developed in a flight simulator. Full guidance is provided throughout the approach by a Collins Radio Company three-dimensional area navigation (RNAV) system which was modified to provide the two-segment approach capabilities. Modifications to the basic RNAV software included safety protection logic considered necessary for an operationally acceptable two-segment system. With an aircraft out of revenue service, the system was refined and extensively flight tested, and the profile and procedures were evaluated by representatives of the airlines, airframe manufacturers, the Air Line Pilots Association, and the Federal Aviation Adminstration. The system was determined to be safe and operationally acceptable. It was then placed into scheduled airline service for an evaluation during which 180 approaches were flown by 48 airline pilots. The approach was determined to be compatible with the airline operational environment, although operation of the RNAV system in the existing terminal area air traffic control environment was difficult.

Abstract: Increasing operating cost of marine geophysical surveys, coupled with expansion of surveys into deeper water and further from shore have placed new demands for reliability in navigation Although numerous navigational systems are capable of supplying good data in specific operating environments around the world, most become marginal in the more remote deeper water areas Such limitations have been countered through use of hybrid navigational configurations which often are little more than a lashing together of backup systems A shortcoming in these hybrid systems is that various components may be based upon different geodetic earth models, with the consequent introduction of ambiguities and uncertainties into both real-time navigation and postplot solutions To resolve such ambiguities and to provide world-wide operation for all typically encountered conditions, a system was developed that provides optimal real-time position information based upon the navigation satellite datum The system is configured around a software program that optimally combines digitized data from whichever sensor units are active Included among the sensor types are all radio navigation aids, a doppler sonar, a satellite receiver, and an inertial platform The integrated character of the system allows continual automatic adjustment to optimal solutions during activation or de-activation of individual sensors Furthermore, the system is mechanized to provide continuous steerage information, thus eliminating the need for preplots which are required for most radio navigation aids The software allows stand-alone operation of each component system in addition to the optimum blending of all available data Thus, digitally recorded output from the various systems can be evaluated separately during postplot analysis

Abstract: A 70-hour flight test evaluation of an Omega navigation system was performed using a Piper Cherokee 180, to determine the feasibility of Omega for worldwide general aviation navigation. Measurements were made of position accuracy, noise phenomena, and signal to noise ratio. It was found that Omega accuracy is essentially insensitive to local geography, but that there are isolated local interference phenomena associated with radio transmitters, although the strongest noise source observed was due to the onboard power source for the VHF comm/nav radio. An occurrence of lane jumps was observed when attempting to navigate with one weak station.

Abstract: A computer simulation was modified to generate a suitable data base for performance of an avionics sensitivity study during RNAV/MLS transition. The avionics sensitivity data provides information necessary to establish requirements for additional guidance law design during transition and to establish airspace requirements for maneuvering to null out any residual RNAV errors upon MLS transition. The data base is also beneficial as planning information for subsequent flight testing.