CRE Documentation and Reporting 2 — Questions and Answers
Question 1: Which document formally captures the agreed-upon reliability requirements between a customer and supplier at the start of a program?
- Reliability Demonstration Plan
- Statement of Work (SOW)
- Reliability Requirements Specification (Correct answer)
- Test and Evaluation Master Plan
Correct answer: Reliability Requirements Specification
A Reliability Requirements Specification documents the mutually agreed reliability goals, constraints, and metrics before program execution begins.
Question 2: In a Failure Mode, Effects, and Criticality Analysis (FMECA) report, the 'criticality number' for each failure mode is calculated using which two parameters?
- Severity and detection rating
- Failure rate and failure mode ratio (Correct answer)
- Occurrence probability and severity class
- RPN and detection score
Correct answer: Failure rate and failure mode ratio
MIL-STD-1629A defines criticality number Cm as the product of failure rate, failure mode ratio, and mission time for quantitative FMECA.
Question 3: A reliability engineer needs to communicate a sudden field failure spike to executive leadership. Which reporting format is MOST appropriate?
- Detailed FRACAS database extract
- Executive dashboard with trend charts and key metrics (Correct answer)
- Full fault tree analysis report
- Raw warranty claims spreadsheet
Correct answer: Executive dashboard with trend charts and key metrics
Executive dashboards condense complex reliability data into visual trends and key metrics suited for senior leadership decision-making.
Question 4: What is the primary purpose of a 'lessons learned' document in a reliability engineering program?
- To assign blame for past failures
- To satisfy audit requirements only
- To transfer knowledge from completed programs to future ones (Correct answer)
- To document corrective actions already implemented
Correct answer: To transfer knowledge from completed programs to future ones
Lessons learned capture insights from both successes and failures so future programs can avoid repeating mistakes and replicate successes.
Question 5: Which section of a Reliability Test Report typically documents the statistical confidence level and sample size justification?
- Executive Summary
- Test Objectives and Scope
- Test Plan Rationale and Statistical Basis (Correct answer)
- Failure Analysis Results
Correct answer: Test Plan Rationale and Statistical Basis
The test plan rationale section documents the statistical methodology, confidence levels, and sample size calculations that underpin the test design.
Question 6: An 8D corrective action report requires 'D4: Root Cause Identification.' Which tool is MOST commonly documented in this step?
- Pareto chart of symptom frequency
- Is/Is Not analysis combined with fishbone diagram (Correct answer)
- Control chart of process variation
- FMEA severity ranking table
Correct answer: Is/Is Not analysis combined with fishbone diagram
The 8D D4 step uses Is/Is Not analysis to bound the problem and fishbone (Ishikawa) diagrams to identify the verified root cause.
Question 7: When documenting reliability predictions per MIL-HDBK-217, which information is mandatory to report for each part?
- Vendor name and purchase order number
- Part failure rate, quality level, and operating stress factors (Correct answer)
- Component serial number and installation date
- MTBF warranty claim history
Correct answer: Part failure rate, quality level, and operating stress factors
MIL-HDBK-217 predictions require documenting each part's base failure rate, quality level, and applied stress derating factors to justify the calculated failure rate.
CRE Documentation and Reporting 2
Which document formally captures the agreed-upon reliability requirements between a customer and supplier at the start of a program?