In Flight Every pilot knows you never leave the ground without a fully charged oxygen system. It is a matter of life and death because of a condition known as hypoxia.
Hypoxia is a condition caused by a decrease in available oxygen at higher altitudes. This condition can affect individuals differently, but following are what some people may experience at various altitudes.
5, 000 ft.
Night vision slightly impaired.
Drowsiness, fatigue, headache, and impaired judgement. Symptoms are generally undetectable during flights of less than one hour. However, on longer flights (especially four hours or more), symptoms can become progressively more noticeable and dangerous.14,000 ft.
Some people experience euphoria, become belligerent, exhibit overconfidence, impaired judgement and a decreased attention span. Some are likely to experience decreased muscle control, blurred vision, memory lapses and may even pass-out. The longer the flight, the more noticeable the symptoms which nearly always occur during flights of two or more hours.
Above 14,000 ft.
Same symptoms as above but they occur more rapidly as the altitude increases. Serious handicap and collapse may occur at 17,000 ft. and smokers will experience these symptoms 3,000 to 4,000 feet lower.The Portable Oxygen System Pilots are responsible for ensuring that supplemental oxygen is available for all occupants on board his/her plane especially above 15,000 feet. Therefore, most private pilots rely on a portable oxygen system that includes a pressurized cylinder charged with aviator grade oxygen, control valves, readout gauges, and breathing equipment which may be either a cannula or a mask. --more