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This report describes the progress of the NAVFAC sponsored cable development program for suspended sensor applications from FY-1971 through FY-1975; it delineates the technology developed and provides information that can guide component selection for other suspended cable applications. The major objective of the program was to demonstrate the feasibility of a new technology developed explicitly for suspended sensor systems in the ocean. Although the principal emphasis was placed on the major component - the cable - the technology was developed from an overall point of view for the entire system. The report describes electromechanical cable developments in steel and synthetic strength members; cable construction; fairing; buoyancy; acoustic sensors; special eletrical conductorsl insulation molding and bonding; array design, fabrication, and testing; complete dynamic and stress analysis of a suspended system; and sea usage to date, which has demonstrated the advantages of the newer technology and lighter weight systems. (Author)

The Advanced Diagnostic Sensor Applications Technology (ADSAT) Program was a research and development program aimed at the exploration of several recently developed sensors which have application potential for the detection of jet engine malfunctions and degradations and at the integration of these sensors into the existing Air Force Engine Diagnostic System. Several sensors were fabricated and purchased, tested at the contractor's facilities, and integrated into the existing Air Force Exploratory Model Turbine Diagnostic System (TEDS). An overall system description was presented in the TEDS final report, AFAPL-TR-71-33. After preliminary testing of the individual sensors, they were installed on a J57 engine at Wright Patterson Air Force Base in Dayton, Ohio. The sensors studied include (1) an Infrared pyrometer for turbine blade temperature measurement, (2) a capacitive proximity probe for turbine blade tip condition detection, (3) thermocouples and resistive sensors for turbine inlet guide vane temperature measurement, (4) an optical oil quality sensor for lube condition monitoring, (5) dynamic pressure sensors for fuel pump and control mechanical degradation detection, (6) ultrasonic vibration transducers for moving part mechanical degradation detection, and (7) a tangential pitot pressure sensor for compressor stall sensing. (Author)

The Frank J. Seiler Research Laboratory has developed a flexural rigidity sensor (FRS) that now makes it possible to measure dynamic flexural deformations of structures in the presence of large linear vibrations. Measurements of this type can be used to provide a spectral signature of a rigid member under varying loading conditions. Changes in the loading or flexural stiffness of the member can be readily identified by characteristic shifts in these spectral signatures. Using these methods, impending structural failures may be identified using the FRS. This compact device is completely portable and has a resolution of 10 to the minus 9th power radian with a flat response from dc to 50 kHz. It offers a wide and intriguing range of applications in non-destructive testing of civil engineering and aerospace structures. (Author)

Maintenance data from UH-1D/H and AH-1G aircraft was evaluated in support of the goal of a successful automatic diagnostic and inspection system for Army aircraft. Analysis of maintenance data from a variety of sources identified components and systems in terms of high failure rate, high inspection time, high fault isolation time, high replacement time, or high parts cost, or that contribute significantly and directly to secondary damage, require depot overhaul, and critically affect flight safety. Recommendations are given as to those components and/or systems that are amenable to automatic diagnostic techniques. (Author)

This report summarizes the results of a very brief investigation of the state-of-the-art in microprocessor technology and its applicability to the processing requirements for a range of ground sensor applications. From available devices hardware configurations and logic outlines were suggested for three sensor applications ranging from magnetic/seismic line type to acoustic point devices. Based upon the work one concludes that microprocessors can provide the basis for general purpose sensor processing modules. However, the feasibility of this approach would require a much more detailed study of cost and power considerations as compared to the conventional hardware processing techniques., See also Volume 2, AD/A-002 667.

The theories for the determination of the Newtonian gravitation constant (G) and the earth's gravitational constant (GM) have been examined. Two experiments have been considered for determining the Newtonian constant, one of which appears to be capable of improving the accuracy of measurement of G by at least one order of magnitude. Measurement of GM by gradient techniques does not, however, appear to yield any improved accuracy. Experimental tests have demonstrated that the rotating gravitational gradient sensor concept is capable of measuring static gravitational gradients in the 1 g environment of the earth and that the sensor designs have the accuracy needed for useful measurements (5 to the minus 9th power/square sec). A design of a prototype transportable gradiometer system has been completed and a program for fabrication and test has been established. A study of sensor applications indicates that these sensors can aid in airborne gravimetry surveys by improving the guidance system performance and by obtaining a real time measurement of local gravity anomalies.

This report describes the analytical and experimental work done to investigate the advantages, design tradeoffs, and potential problems associated with the use of ultraviolet and near-ultraviolet lasers in very high resolution and very wide bandwidth precision raster type laser beam recorders (LBR's) for side-looking radar and other reconnaissance sensor applications. Recommended designs are presented for each of the major subsystems of the recorder, including the traveling-wave light modulator design, and a new type of high speed mirror scanner employing thermoelectrically pumped Freon as a lubricant in a completely closed system. The recommended (most promising) laser for this application is the ruggedized Helium-Cadmium gas laser. Recommended photographic films are also presented and discussed. Two conceptual designs for precision wide-bandwidth LBR's are described, one using a flat-field approach and one employing a curved field configuration. A comprehensive set of test procedures suitable for evaluating the performance of this class of precision recorder is also presented. The test procedures cover measurement of spot velocity uniformity, raster line spacing uniformity, line straightness and skew, system modulation transfer function (MTF), and other important performance factors. (Author)