**2. Methodology**

This section presents the methodology for determining time-dependent failure rates of different failure modes using field data. For this purpose, the lifetime distribution is presented, which can be used to represent the field data. In order to be able to examine different failure modes in relation to each other, censoring methods are introduced and bias correction is applied due to limited sample sizes in some cases. Finally, the derivation of the failure rate from the obtained parameters is presented, which can then be used to calculate the time-dependent failure rates.
