Predicting the reliability of military vehicles has traditionally concentra
ted on estimation using failure data gathered during trials or use. However
, it is increasingly recognised that predicting reliability earlier in the
life cycle, using design and process capability evidence, is one way of imp
roving predictions and positively influencing reliability. This article pre
sents the use of Bayesian belief networks (BBNs) as a decision support tool
to achieve these twin goals. The BBN models presented are built into the T
RACS software tool, which is in daily use within DERA Land Systems.