SAFA Skysailor Magazine

48 SKY SAILOR September-October-November | SPRING 2025 edness, fatigue, difficulty processing visual information, impaired reasoning and judgement, hyperventilation, muscular weak- ness and eventually loss of consciousness and death of brain cells.’ (Source: https:// consultation.casa.gov.au/regulatory-pro- gram/caap20_4/supporting_documents/ Draft%20CAAP%2020.401%20v1.0.PDF ) * Hypoxia – 2025 Refresh * That CAAP is currently no longer available on the CASA website, nor can I find any Ad- visory Circular or CAAP documents that refer to hypoxiaa, but that link above still works. There are a couple of Advisory Circulars that talk about oxygen delivery systems. Hypoxia is usually classified into four types: Hypoxic: results when there is a reduction of a partial pressure of oxygen in the breathed air, or some physiological reasons. Anaemic: caused by reduced haemo- globin content. It’s commonly attributed to poor nutritional state, but carbon monoxide, nitrates and sulfa drugs can also hog haemoglobin reducing the oxygen carrying capacity of your blood. Stagnant or Hypokinetic: this form is due to a malfunction in the circulatory system; the blood is good, but it can’t be circulated adequately. Histotoxic: occurs when the supply of oxygen is normal, but the utilisation by the bodies’ cells is interfered with by substances such as alcohol, narcotics or poisons such as cyanide. While all types may occur while we’re flying, the one we are primarily interested in is Hypoxic Hypoxia, and this occurs when breathing air at reduced pressure. The reduced air pressure at altitude results