A qualitative assessment of a passive low attitude terrain following system for tactical bombers as modeled on the Tornado aircraft

Although combat aircraft designers face similar design conflicts as their commercial and civil aerospace contemporaries, they also experience the additional challenge of designing a vehicle that is survivable in the combat environment. The military user defines the expected threat environment for the vehicle. Based on this characterization, the designer incorporates survivability characteristics to reduce the aircraft's susceptibility and vulnerability. The lengthy design, prototype, test, and production process leaves the new aircraft exposed to new or improved threats fielded during that time. This evolving threat necessitates a continuous cycle of modifications and improvements throughout the vehicle's life to ensure that the aircraft remains effective and survivable. The Tornado GR Mk1 Multi-Role Combat Airplane is a twin engine, fighter-bomber representative of high speed, low altitude, all weather aircraft designed to penetrate enemy defenses using sophisticated avionics and terrain following capabilities. Other examples of this class include the U. S Navy's A-6 and the Air Force's B-52, F-117, B-1, and B-2 aircraft. The low altitude radar penetration systems, while extremely capable, can be vulnerable to jamming, deception, and adverse weather. Additionally, the use of terrain following radar can increase an aircraft's susceptibility by hostile Electronic Support Measures (ESM) systems and increases its susceptibility to integrated air defense systems. The employment of highly accurate position and velocity data from the NAVSTAR Global Positioning System (GPS), together with the Digital Terrain Elevation Data (DTED) could provide a beneficial navigation and survivability enhancement design for use by this type of aircraft. The objectives of this thesis are: (1) to propose a model of an alternate passive navigation and terrain following capability that could be easily incorporated into the Tornado and other aircraft in its category, (2) to evaluate the error contributions of components of the proposed penetration system and quantify the possible low altitude flight capabilities of an aircraft using the system, (3) qualitatively assess the technical, operational, and economical feasibility of the system and (4) evaluate potential susceptibility and survivability benefits of the system. These goals will be achieved by researching the technical and operational flight test data for the components of the passive penetration system and combining that information with flight test information collected during an assessment of the Tornado aircraft (USNTPS DT-II). Quantitative assessments of the capability of the proposed system will be based on analysis of literature specifications augmented by flight test results when available. A simple model of the penetration system, showing the required data inputs and control outputs, will be used to examine the potential incorporation methodology and the technical mechanization. Finally, use of a simplified scenario in a survivability model will provide an assessment of the capability and potential survivability improvements from retrofitting the passive system in the Tornado aircraft.