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Malaysia Airlines Flight 370
Published in Elizabeth A. Hoppe, Ethical Issues in Aviation, 2018
Mechanical failure could have led to the rapid decompression of the aircraft. In the event of cabin decompression, the pilots could have lost control of the 777, due to being victims of hypoxia. Hypoxia is a physical condition that is related to low oxygen levels in the blood stream and tissues. This condition could have led to the loss of situational awareness by the flight crew, thus leading to problematic decision-making, including the inability to react appropriately to the emergency. This scenario also seems plausible due to the alteration in the flight path of the aircraft. The Inmarsat satellite data shows that the aircraft made a complete turnaround, which could have occurred before the pilots lost control of the aircraft.
Basic Physiology and the Effects of Flight
Published in Roger G Green, Helen Muir, Melanie James, David Gradwell, Roger L Green, Human Factors for Pilots, 2017
Roger G Green, Helen Muir, Melanie James, David Gradwell, Roger L Green
Hypoxia is the term used to describe the condition which occurs when the oxygen available to the tissues is insufficient to meet their needs. There are many causes, but in aviation the greatest risk of hypoxia arises as a result of ascent to altitude with its associated fall in ambient pressure.
Aviation Physiology
Published in Monica Martinussen, David R. Hunter, Aviation Psychology and Human Factors, 2017
Monica Martinussen, David R. Hunter
This is the hypoxia typically associated with high altitude flight. Your body cannot absorb adequate oxygen because there is not enough pressure to force the oxygen molecules through membranes of the respiratory system.
Integrating physiological monitoring systems in military aviation: a brief narrative review of its importance, opportunities, and risks
Published in Ergonomics, 2023
David M. Shaw, John W. Harrell
Hypoxia is a state of inadequate oxygen availability to maintain normal physiological function. The hallmark indicator of a hypoxic environment is hypoxaemia, a reduction in arterial PO2, which is typically determined by reduced peripheral blood haemoglobin-oxygen saturation (SpO2) to <88–92%. Cognition, vision, and motor-performance are impaired, particularly under severe hypoxia (e.g. exposure to >20,000 ft PO2 equivalent) (Shaw, Cabre, and Gant 2021). Hypoxia also reduces G-tolerance (Besch et al. 1994) and decreases AGSM performance due to impaired muscular performance (Millet et al. 2012). Hypoxaemia can also reduce cerebral tissue oxygenation (Ottestad, Kåsin, and Høiseth 2018; Phillips et al. 2009; Williams et al. 2019), despite an increase in cerebral blood flow (CBF) (Ainslie, Hoiland, and Bailey 2016; Hoiland et al. 2016). Ventilation increases in an attempt to elevate alveolar PO2 and consequently decreases alveolar and arterial carbon dioxide, leading to hypocapnia (see below). Heart rate (HR) increases (Botek et al. 2015; Krejčí, Botek, and McKune 2018), HR variability (HRV) decreases (Botek et al. 2015; Krejčí, Botek, and McKune 2018) and electroencephalogram (EEG) power amplitudes are altered (Rice et al. 2019). These physiological responses appear greatest with hypobaric compared with normobaric hypoxia (Coppel et al. 2015).
Plateau effect on driver’s hazard perception response mode: Graph construction approach
Published in Journal of Transportation Safety & Security, 2023
Chenzhu Wang, Mingyu Hou, Fei Chen, Jiayun Zhu, Jianchuan Cheng, Wu Bo, Ping Zhang, Said M. Easa
Known as “the Roof of the World,” the Qinghai–Tibet Plateau in China has an average altitude of more than 4,500 m (H. Sun, 2010), where the partial pressure of oxygen (about 11 kPa) and atmospheric pressure (about 53 kPa) are lower than the those on the plain. Therefore, after entering the plateau, the respiratory center is indirectly stimulated through the peripheral chemoreceptors (mainly the carotid body), resulting in an early increase in ventilation and subsequent altitude sickness. Altitude sickness is the physiological discomfort caused by hypoxia, primarily as headache, dizziness, cardiopalmus, shortness of breath, and even temporary blackout (Anand & Wu, 2004). After being in a plateau area for some time, the body can adapt, with significantly relieved initial hypoxia symptoms and altitude acclimation. Then the body can inhale more oxygen to compensate, during a gradual transition to stable adaptation (around 1 to 3 months; Li et al., 2012).
Exposure to hypoxia impairs helicopter pilots’ awareness of environment
Published in Ergonomics, 2021
Yuval Steinman, Eric Groen, Monique H. W. Frings-Dresen
Helicopter cabins are not pressurised and are often not equipped with oxygen systems. Therefore, hypoxia is a hazard to helicopter pilots flying at altitude. Hypoxia is a state of insufficient oxygen in the blood, tissues, and/or cells (Boshers 2015). To prevent hypoxia-related incidents there are altitude and flight duration restrictions for helicopter crews. For example, the Royal Netherlands Air Force allows their helicopter pilots to fly up to 3962 m (13,000 ft) for a maximum duration of 30 min, whereas pilots of the United States Air Force are allowed to fly 30 min at 4267 m (14,000 ft) (Command AFSO, 2017). Nonetheless, helicopter pilots have reported experiencing hypoxia symptoms even at altitudes below 3048 m (10,000 ft), where it is considered safe to fly (Haerkens and Steen 2007; Nishi 2011; Smith 2005).