No description available.

The focus of this work is the investigation of the complex compressible flow phenomena associated with high speed aerial weapons. A three dimen- sional multiblock finite volume flow solver was developed with the aim of studying the aerodynamics of missile configurations and their component structures. The first component of the study involved the aerodynamic investigation of the isolated components used in the design of conventional missile config- urations. The computational study of nine ogive-cylinder body experimental test cases is presented together with a new interpretation of the complex vortical flow including the windward appearance of a 'vortex shock wave'. In addition, a simple modification to improve the accuracy of the Baldwin- Lomax/Degani-Schi fl'' turbulence model is put forward, and the phenomenon of 'phantom vorticity' in Euler solutions and its alleviation are described. Inclined Delta Wings in supersonic flow were computed in order to study the aerodynamics of wings alone, and in particular the vortex-shock interactions which occur on their leeward surfaces. The second component of the study was the computational and experimen- tal investigation of a generic cruciform missile configuration. The compli- cated interactions between shock waves and boundary/shear layers that are seen to occur around and in the wake of the cruciform wing arrangement were studied and described. The third component of the research involved an assessment of the pre- diction technologies used in the design of modern weapons. In particular the role of Computational Fluid Dynamics in the process of design.

An opportunistic array is an integrated ship-wide digital phased-array radar, where antenna elements are placed at available open areas over the entire shipâ s length. Such an array has the potential to fulfill many of the Navyâ s missions, including ballistic missile defence (BMD) where the radar mission encompasses exo-atmospheric surveillance, tracking and preliminary discrimination. Advantages of opportunistic arrays include enhanced stealth â since low-profile antennas reduce the shipâ s RCS; high angular resolution â as the entire shipâ s length forms the â apertureâ and produces a narrow beamwidth; and potentially lower costs â through the use of COTS technology and a flexible digital antenna architecture that reduces the number of distinct radar systems required. This research first investigated the opportunistic array concept in the context of BMD. A system level tradeoff was performed to size the system and verify that detection ranges greater than 1000 km could be achieved. Next, the research focused on designing a low-profile, broad-band U-slot microstrip patch antenna. Theoretical calculations and parametric studies were performed to develop an antenna element that could operate in the upper VHF/lower UHF frequencies. A set of simple design procedures is proposed to provide approximate rules that result in a good â first-passâ design with prescribed characteristics that require minimal tuning.

This is an examination of the determinants of weapons succession as they have operated in the United States since the early 1970s. It takes as its subject matter the joint-service development of the modular cruise missile. both strategic and tactical. What this example also provides is a chance to study the start-up of a programme which did not initially represent a follow-on to an existing system. Moreover. the revival of cruise missile development in the UnHed States. unlike the ground-breaking programmes which had led to the atomic bomb. the ICBM and the SlBM. was achieved against a background of apathy and resistance from the armed services. This study has attempted a critique both of orthodox analyses of the acquisition of weapons. which have explained armaments as a rational response to an external threat. and of theories of bureaucratic politics. which have largely been blind to the role of industry. This study concludes that to understand the determinants of weapons succession. it is necessary to examine the social structure of defence technology. This involves examining the role of the producers of military technology (the defence prime contractors). and the consumers (government and the services) and the relationship which exists between them. The cruise missile programmes constituted a challenge both to the existing missions of the services and the influence of the dominant aerospace corporations. It was a challenge which did not succeed. The cruise missile was assimilated by the services in ways which enhanced their dominant missions which are associated with particular weapons platforms. most notably the penetrating bomber and the aircraft carrier. Joint service development of the missile was staunchly resisted and is not part of the follow-on cruise missile programmes. The attempts made by the Joint Cruise Missile Project Office to reform acquisition were unsuccessful. Design-to-cost, second production sourcing and increased competition did not control the cost of the weapon. Indeed, the increasing involvement of aerospace companies in el ectronics has meant that they have been abl e to re-assert thei r dominant position as the main defence contractors. despite a severe slump in orders in the early 1970s. Domestic attempts to curb the weapons succession process have been thwarted by the influence of its dominant institutions in the United States. Yet the same can also be seen to apply to attempts at curbing the arms build up through direct external negotiations. It is not simply that bilateral nuclear arms control negotiations have failed to reduce the demand for weaponry: arms control has become an important demand factor in the weapons succession process. stimulating new weapons developments and legitimating weapons deployments. What this study demonstrates is that, to understand the nature of the arsenal, a range of dominant institutional influences must be addressed. Reform or change will only come about if the 'social stucture l of weapons technology is first understood.

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No description available.

Thesis (M.S. in Defense Analysis)--Naval Postgraduate School, December 2006. / Thesis Advisor(s): Frank Giordano. "December 2006." Includes bibliographical references (p. 71-73). Also available in print.

We describe major enhancements to the missile defense planning aid "JOINT DEFENDER" (JDEF). JDEF is the first system that shows how to evaluate and exploit new and anticipated improvements in interceptors, long-range surveillance and tracking capabilities, networked communications, and the ability of detecting platforms to cue intercepting ones downrange. We want to improve system-wide effectiveness, gauged here by the reduction of expected damage inflicted. We defend an asset list (DAL) of targets, characterized by their locations and values to us. Our defenders include pure "LOOKERs," radars and sensors of enemy missile launches, and "SHOOTERs," platforms with means to both detect and intercept enemy launches. JDEF optimally positions platforms that can be moved, and prescribes what each platform should do. JDEF can estimate the value to either opponent of secrecy, deception, or intelligence. JDEF is the only missile defense planning system using formal optimization. Among many advantages this conveys, JDEF is able to unambiguously quantify the difference among disparate plans. Although the JDEF planner can manually control any detail, the planner is well advised to let optimization suggest where to start.

A near-optimal guidance law has been developed using the direct method of calculus of variations that maximizes the kinetic energy transfer from a surface-launched missile upon interception to a ballistic missile target during the boost phase of flight. Mathematical models of a North Korean Taep'o-dong II (TD-2) medium-range ballistic missile and a Raytheon Standard Missile 6 (SM-6) interceptor are used to demonstrate the guidance lawâ s performance. This law will utilize the SM-6â s onboard computer and active radar sensors to independently predict an intercept point, solve the two-point boundary value problem, and determine a near-optimal flight path to that point. Determining a truly optimal flight path would require significant computing power and time, while a near-optimal flight path can be calculated onboard the interceptor and updated in real time without significant changes to the interceptorâ s hardware. That near-optimal guidance path is then converted into a set of command functions and fed back into the control computer of the interceptor. By modifying the second and third derivatives of the two-point boundary value problem, the intercept conditions can be varied to study their effects upon the optimal flight path regarding the maximization of kinetic energy upon impact. / US Navy (USN) author.

Thesis. 1975. Sc.D.--Massachusetts Institute of Technology. Dept. of Aeronautics and Astronautics. / Vita. / Bibliography: leaves 318-319. / Sc.D.