Accession Number:

ADA164747

Title:

Reliability Prediction for Spacecraft

Descriptive Note:

Final rept. Mar 83-Jan 85,

Corporate Author:

SOHAR INC LOS ANGELES CA

Personal Author(s):

Report Date:

1985-12-01

Pagination or Media Count:

152.0

Abstract:

This study provides the basis for improving the utility of Mil-Hdbk- 217 for reliability prediction of spacecraft components and systems. The reliability performance histories of 300 satellite vehicles, which were launched between the early 1960s through Jan 84, were reviewed and analyzed during the course of the study. Analysis of over 2500 reports of malfunctios indicated strong evidence of a decreasing failure rate with time in orbit. The cause for the decreasing hazard was found to be traceable primarily to design and environmental causes. In general, however, it was found that current predictions overestimate the failure rate by at least a factor of two and that the excess of predicted over observed failures increases with time in orbit. Three methods are provided for spacecraft reliability prediction. In order to account for the decreasing hazard, two of the procedures use a Weibull model with parameters based upon similar spacecraft mission types. A third method uses modifications of Mil-Hdbk-217 procedures to account for the overestimation of failure rates which result when current procedures are used.

Subject Categories:

  • Statistics and Probability
  • Manufacturing and Industrial Engineering and Control of Production Systems
  • Unmanned Spacecraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE