Fatigue Risk Management


Sleepiness model #

FlightLog comes within an elaborated Fatigue module.

Once your roster is imported, this module will show you all your flights to come.

The app is calculating the fatigue caused by your flights, using a bio-mathematical process called Three-Process Model (TPM) of Alertness, elaborated by Akersted.

TPM includes a Process C that represents sleepiness due to circadian influences and has a sinusoidal form with an afternoon peak, and a Process S that is an exponential function of the time since awakening. The third Process U that represents a 12-h period is associated with the afternoon reduction in alertness. The model also includes a sleep inertia function (process W) that initially reduces alertness at the time of waking up with an exponential recovery.

The duty time is computed as : no sleep allowed 2.5h before flight and 2h after.

The model also takes into account the jetlag : we modeled acclimatization to be made continuously, assuming a default daily rate of 30% of the difference between the acclimatized time and local time. Then the model is converted to match the Karolinska Sleepiness Scale (1-9 levels).
You can setup your personal settings like age and sleeping type, setup your actual alertness level, and play with several options like activate jetlag, local night rest, setting up a nap on your next flight, in order to optimize your alertness at landing time and your rest at destination.
Obviously the model, validated for crews (the study was partly funded by Vinnova Sweden (to Stress Research Institute) and partly by Jeppesen AB) is subject to individual differences and applies to 75% of the population.


CrewAlert Pro #


CrewAlert Pro is a iOS app from Jeppesen.

CrewAlert Pro runs on all iOS devices and has a rich feature set enabling :

– Data collection and fatigue reporting
– Prediction of fatigue
– Storing multiple parallel scenarios
– Loading rosters automatically
– Reading sleep from Apple Health
– Suggesting fatigue mitigations

As CrewAlert is based on scenario, you should have to fill all your roster to analyse your predictive fatigue. By pushing the SEND TO CREWALERT PRO button, FlightLog sends your flight data (real flights : 15 previous days, roster : 60 next coming days). FlightLog will consider extra crew member if flight time is over 9h30, and calculate your main base. Obviously you can edit these presets within CrewAlert app.

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