Transient fatigue risk is possible to predict with fair accuracy, for a population of crew members. The risk will depend mainly on three factors; time of day, time awake and sleep debt. At any given point in time, the transient (or ’acute’) fatigue risk levels will depend almost exclusively on what has occured in the 48 hours prior. And there is a good correlation to the duty roster regarding duty times, durations and rest times.
Cumulative fatigue risk, on the other hand, is built up over much longer periods, like weeks or months. This risk factor, adding to the transient fatigue, has turned out to be much more elusive for the scientists to nail down. It is not yet possible to make a good prediction from data available to a typical airline. The reason we struggle to understand cumulative fatigue is in part a shortage of detailed long-term data, and in part that cumulative fatigue is a multi-faceted ’creature’ where personal matters in the life of crew also play a part. There is a multitude of stressors that may lead to stress, which in turn, if not properly managed, may result in symptoms. These symptoms could be sleep-related problems, further elevating fatigue risk.
Still, there are good and effective mechanisms available, employed by many airlines today, for reducing and minimizing cumulative fatigue. These mechanisms recognize that different crew members have different needs and also apply caution in the distribution of workload between crew. For many operators, these pro-active scheduling praticies are automated and regularly fine-tuned in dialogue with crew representatives such as unions. Examples here are buffers, standby management, fair share (or 'fairness'), preferential bidding, trip trading and special contracts. All of them commonly used and going far beyond regulatory requirements, whilst making good financial sense contributing to the bottom line.
Please find through this link a document providing guidance outlining a best practice for crew management, adressing each step of the crew management process. Enjoy.
Comments