It may be something you have taken for granted and stopped questioning long ago. Perhaps you, without being able to fully articulate it, have had a vague feeling of discomfort regarding your current FRM approach? You are not alone. Only too often we meet up with operators that use, how to put it politely..., far from ideal metrics in their FRM work. It may go something like this:
- Our main metric we track is the number of published rosters containing activities predicted by our fatigue model to be worse than a certain number. We use this metric to track improvement/deterioration over time.
- So, putting your fatiguing activities on as few rosters as possible shows you have improved?
- Eh... well... what? Hmm...
- And, knowing the shortcomings of fatigue models, would you say being just slightly better than that magic number, makes a difference to being just slightly worse?
- Of course not, but we need to draw the line somewhere. Don't we? Or? Hmm...
Having well-considered metrics is crucial, not only for follow-up but also for proactive control and reduction of risk. In terms of flight safety, an operator will be exposed to an overall level of fatigue risk which can be seen as the sum of probability over allthe flights operated. All pilots will carry a small contribution to that risk, springing from the very small likelihood of reduced alertness leading in to either a lapse, slip, mistake, or violation contributing to an incident or accident. That overall exposure is what matters the most.
Take a closer look at your metrics. Are they; data-driven, based on science, reflective of risk on continuous scales, and genuinely representative? Are you sensing something is wrong?
Read more here about the best practice for quantifying fatigue risk.