IDEF ZERO

Node A6 · Acronym decoder

MTTR

Mean Time To Repair

What it actually means

The average time to restore a failed system to operation — the headline maintainability metric, driven by fault detection and isolation time, accessibility, spares availability, and task design. Paired with MTBF it determines availability: a system that fails rarely but takes weeks to fix can still be unavailable when needed.

Where you'll meet it

Maintainability requirements and demonstrations, availability calculations.

Related terms

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