Aerospace & Defense Manufacturing worked example

Nonconformance Disposition Time at 98% engineering and customer approval allowance: a worked example in aerospace & defense manufacturing

What does the result look like when engineering and customer approval allowance reaches 98%? The full calculation is worked below with real intermediate numbers. a program manager or quality engineer needs to estimate how long nonconforming flight hardware will sit in MRB review

The inputs for this scenario

  • Open NCRs awaiting MRB disposition: 42 NCRs (unchanged)
  • MRB disposition review pace: 0.45 NCRs/min (unchanged)
  • Engineering and customer approval allowance: 98 % (raised for this scenario; the documented default is 85)

Working through the calculation

  • Applying the documented formula (Base MRB review time = nonconformance records รท disposition review pace) to the inputs above produces each figure below.
  • At this operating point the engine returns 185 MRB hr for total nonconformance disposition time, the number this scenario is built around.
  • At this operating point the engine returns 93.33 MRB hr for base mrb review time.
  • At this operating point the engine returns 98 % for engineering and customer approval allowance.
  • At this operating point the engine returns 0.45 NCRs/min for disposition review pace.

How this compares with the baseline

  • Against the tool's baseline example, where engineering and customer approval allowance sits at 85% and the headline result is 173 MRB hr, this scenario comes in 7.03% above the baseline at 185 MRB hr.
  • A figure at this level is achievable when engineering and customer approval allowance is genuinely sustained, not just peaked for a shift. The single allowance percentage assumes a uniform mix of disposition types; a backlog skewed toward repair or use-as-is dispositions needing source/customer approval will run far longer than the average implies.

Results at a glance

  • Total nonconformance disposition time: 185 MRB hr (headline result)
  • Base MRB review time: 93.33 MRB hr
  • Engineering and customer approval allowance: 98 %
  • Disposition review pace: 0.45 NCRs/min

Run it with your numbers

  • Every input above is editable in the live Nonconformance Disposition Time calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.