Maintenance & Reliability worked example

Reliability Percentage at 71% target reliability: a worked example

Suppose target reliability falls to 71%. This page works the full calculation at that level so you can see exactly which result moves and by how much. Express mission reliability as a percentage using an equivalent successful-mission count and a target gap.

The inputs for this scenario

  • Equivalent successful missions at time t: 97 missions (held at the documented default)
  • Mission sample basis: 100 missions (held at the documented default)
  • Target reliability: 71 % (the input this scenario stresses; the baseline uses 98)

Working through the calculation

  • The calculation starts from the formula this tool documents: Reliability percentage = equivalent successful missions at time t ÷ mission sample basis × 100.
  • Mission Reliability works out to 97 % at these inputs, and this is the headline figure for the scenario.
  • Gap to Reliability Target works out to -26 points at these inputs.
  • Equivalent Successful Missions works out to 97 count at these inputs.
  • Mission Sample Basis works out to 100 count at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where target reliability sits at 98% and the headline result is 97 %, this scenario lands almost exactly on the baseline at 97 %.
  • It computes the percentage of missions completed successfully against a defined sample basis and the point gap between that result and your reliability target. When the numbers land here, the stressed input is the lever to work; the walkthrough above shows exactly how much each output recovers as it climbs back toward the baseline.

Results at a glance

  • Mission Reliability: 97 % (headline result)
  • Gap to Reliability Target: -26 points
  • Equivalent Successful Missions: 97 count
  • Mission Sample Basis: 100 count

Run it with your numbers

  • To rerun this with your own numbers, open the live Reliability Percentage calculator, set target reliability to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.