NPI, DFM/DFA & Engineering Change worked example

Engineering Rework Hours at 9.2% engineering rework hours utilization target: a worked example

What does the result look like when engineering rework hours utilization target reaches 9.2%? The full calculation is worked below with real intermediate numbers. Use it when engineering rework hours in npi, dfm/dfa and engineering change is being sized against an asset rating.

The inputs for this scenario

  • Engineering rework hours demand: 100 units (unchanged)
  • Engineering rework hours capacity: 1.2 units (unchanged)
  • Engineering rework hours utilization target: 9.2 % (raised for this scenario; the documented default is 8)

Working through the calculation

  • Applying the documented formula (Required engineering rework hours load = engineering rework hours demand รท engineering rework hours utilization target) to the inputs above produces each figure below.
  • At this operating point the engine returns 120 hr for total load, the number this scenario is built around.
  • At this operating point the engine returns 13.04 hr / hr for hourly equivalent.
  • At this operating point the engine returns 100 hr for input load.
  • At this operating point the engine returns 1.2 x for load factor.

How this compares with the baseline

  • Against the tool's baseline example, where engineering rework hours utilization target sits at 8% and the headline result is 120 hr, this scenario lands almost exactly on the baseline at 120 hr.
  • A figure at this level is achievable when engineering rework hours utilization target is genuinely sustained, not just peaked for a shift. It assumes rework tasks are roughly uniform in effort; a model rebuild and a one-line note change carry very different hours, so a blended rate distorts mixed queues.

Results at a glance

  • Total load: 120 hr (headline result)
  • Hourly equivalent: 13.04 hr / hr
  • Input load: 100 hr
  • Load factor: 1.2 x

Run it with your numbers

  • Every input above is editable in the live Engineering Rework Hours calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.