FATIGUE INDICATOR BASED ON ARTERIAL OXYGEN

A new warning system for informing an aircrew member undergoing high acceleration, or other brain oxygen-depleting environmental stressors, of the time remaining before fatigue sets in and the aircrew member will no longer be able to maintain straining maneuvers fighting the effects of high acceleration utilizes the new discovery that pilots and other aircrew members experience performance-ending fatigue at about the same percentage level of blood oxygen saturation. The particular percentage varies individually, but is nearly always the same for a single individual. The warning system uses a non-invasive monitor to measure blood oxygen saturation at different times and to compute from those measurements the amount of time remaining before the individual percentage blood oxygen saturation at which fatigue or exhaustion will occur for that individual will be reached. That remaining time is displayed to the aircrew member on an instrument panel display. The warning system can also be used to display to an aircrew member the time remaining before a preselected level of decreased cognitive function is reached.