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Quach, C. T.

Publications and source records attributed to Quach, C. T..

Determining Availability Characteristics of DSN Data Systems Using Discrepancy Report Data

A reasonably economical way was developed to determine availability characteristics of Deep Space Network (DSN) data systems, subsystems, and assemblies using the DSN discrepancy report (DR) data base and DSN operating schedule and history data bases. Operating mean time between failures (OMTBF), operating mean time to restore service (OMTTRS), and operating functional availability (OFA) can be computed by year, by system, by subsystem, by assembly, and by station. The effort required to produce the desired reports is described, specific data on the telemetry, command, and tracking systems are presented, and major contributors to system outages are identified. Future improvements in preparing and analyzing DR data are also outlined to enhance their use in correcting conditions that lead to outages.

Ruskin, A. M.↗

Techniques for Analysis of DSN 64-meter Antenna Azimuth Bearing Film Height Records

The DSN 64-m antennas use oil pad azimuth thrust bearings. Instrumentation on the bearing pads measures the height of the oil film between the pad and the bearing runner. Techniques to analyze the film height record are developed and discussed. The analysis techniques present the unwieldy data in a compact form for assessment of bearing condition. The techniques are illustrated by analysis of a small sample of film height records from each of the three 64-m antennas. The results show the general condition of the bearings of DSS 43 and DSS 63 as good to excellent, and a DSS 14 as marginal.

Stevens, R.↗