Reliability Management and Leadership
Program structure
A reliability program is a planned set of tasks sized to the product's criticality, cost of failure, and customer expectations. Candidates should recognize the elements: reliability requirements allocation, design reviews, failure reporting and corrective action (FRACAS), supplier control, test planning, and growth management. Leadership sets policy, funds tasks, and enforces gates; the reliability engineer supplies method and data.
Requirements and allocation
Reliability requirements must be quantitative, verifiable, and tied to conditions. Allocation splits a system goal among subsystems using complexity, criticality, or prior field data. Traps include accepting vague requirements ("highly reliable"), allocating without regard to duty cycle, and forgetting to flow requirements to suppliers.
Reviews, metrics, and growth
Design reviews are checkpoints where reliability deliverables (predictions, FMEA, test results) are examined. Reliability growth (Duane, AMSAA/Crow) tracks cumulative MTBF against cumulative test time; the growth rate and management strategy determine whether the program is converging. Watch for questions that confuse demonstration (proving a requirement) with growth (improving a design).
Cost and trade-offs
Life-cycle cost includes acquisition, operation, maintenance, and failure consequences. Reliability investment is justified by reduced warranty, downtime, and safety costs. Beware answers that treat lowest purchase price as lowest cost.
Worked example
A system goal of 0.98 reliability over one year is allocated to three series subsystems by equal apportionment: each gets 0.98^(1/3) = 0.9933. If one subsystem cannot meet that, reallocate using criticality weights or add redundancy, and document the change through configuration control.