Telecommunications & Network Hardware Manufacturing worked example

Service Spare Forecast at 99% line uptime: a worked example

This scenario runs the service spare forecast calculation on the strong side: 99% line uptime, with every other input held at its documented default. Use it when service spare forecast in telecommunications and network hardware manufacturing is being asked to take on more work and you need to know if there is room.

The inputs for this scenario

  • Spare units built per production cycle: 4 units / cycle (unchanged)
  • Production cycles available: 480 cycles (unchanged)
  • Line uptime: 99 % (raised for this scenario; the documented default is 90)
  • First-pass yield: 97 % (unchanged)

Working through the calculation

  • Applying the documented formula (Gross service spare forecast capacity = service spare forecast output per cycle × available service spare forecast cycles) to the inputs above produces each figure below.
  • At this operating point the engine returns 1,844 units for good service spare forecast capacity, the number this scenario is built around.
  • At this operating point the engine returns 1,920 units for gross service spare forecast capacity.
  • At this operating point the engine returns 19.2 units for service spare forecast downtime loss.
  • At this operating point the engine returns 57.02 units for service spare forecast yield loss.

How this compares with the baseline

  • Against the tool's baseline example, where line uptime sits at 90% and the headline result is 1,676 units, this scenario comes in 10% above the baseline at 1,844 units.
  • Use it when planning a spare-parts production run, sizing warranty stock, or checking whether a line can hit a service-level spares target. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Good service spare forecast capacity: 1,844 units (headline result)
  • Gross service spare forecast capacity: 1,920 units
  • Service spare forecast downtime loss: 19.2 units
  • Service spare forecast yield loss: 57.02 units

Run it with your numbers

  • Every input above is editable in the live Service Spare Forecast calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.