Understanding Aviation Hypoxia And Its Adverse Effects On Pilots

Types of Hypoxia

Discuss about the Aviation Hypoxia and Reporting Statistics.

Hypoxia is a deficiency to a human body that occurs as a result of lack of sufficient oxygen in the body. It is tumor caused by a decrease in molecular concentration of the oxygen molecule. In aviation, it is caused by decreased pressure in oxygen emanating from an increase in altitude levels which are beyond human compatibility. Studies show that, for every breath of air, the body absorbs a certain percentage of oxygen. When frying higher, the percentages of air composition remain constant in the atmosphere.

 However, at a peak elevation, the air becomes less dense therefore decreasing the bodies capability to absorb oxygen Gas. A study by (Acharya 2017, P, 696-707) in his journal of informatics shows that atmospheric pressure at 10,000 feet can be approximated to two-thirds of the available oxygen to breathe. This causes depressurization and therefore leads to hypoxia which has remained to be an ever-present disaster in aviation, leading to a lot of negativities such as accidents and poor performance.

This hypoxia disaster has adverse effects to the pilots who engage in aircraft operations. There are different types of Hypoxia associated with a deficiency in oxygen. The common type which is usually experienced at high altitudes where the air density is insufficient is known as hypoxic hypoxia. At higher altitudes, there also exists another form of hypoxia known as hypemic hypoxia. It occurs when the hemoglobin molecule in the blood fails to transport the oxygen inhaled.

 Following studies from a book by (Alexander 2014, P, and 575-242) it can be deduced that this happens because the carbon monoxide gas binds in an irreversible way to the hemoglobin, therefore, loading the body fluid transport mechanism.   Regarding health, the impact of this disaster, to the pilot on the flight, lack of sufficient oxygen at a higher altitude becomes one of the most dangerous occurrences that can lead to sudden death. This happens such that in high altitudes, there exists little oxygen pressure which has little capability to push the oxygen gas into the human lungs, and the bloodstream upon inhaling.

As a result of this decrease in oxygen gas in the body, its supply to body tissues and organs is undermined. This results to malfunctioning of various organs in the body such as brain heart and kidneys. When organs are impaired, human life faces a threat since they are the core organs that support human life. This oxygen starvation is the reason behind death occurrences that are witnessed in aircraft operations. For example, in Greek history, a plane by the name Helios Airways which originated from Larnaca international airport having carried 115 passengers and six cabbing crews faced an accident as a result of oxygen starvation.

Adverse Effects of Hypoxia on Pilots

The incident happened when the crew encountered loss of pressurized oxygen. This made them leave the aircraft swaying in the air and finally landed on the ground leading to the death of a great number of people. Mind disorientation is another effect of hypoxia that happens to a pilot. Since hypoxia is a process which happens bit by bit, one cannot realize its suffering, until he or she experiences oxygen starvation. A Research by (Albright 2015, P, 63) has it that hypoxia gives poor judgment to a pilot.

This happens where at the initial stages of its experience, a pilot feels like having undergone alcohol toxicities. Since oxygen starvation firstly strikes the brain, the critical order of judgment that happens in the brain becomes disoriented. The pilot starts having a misleading pleasant leading to a false sense of security. This can make the pilot fry higher until the hypoxia is severe enough to cause death.

Hypoxia is associated with somebody effects is also termed to bring about motion sickness. This happens where while in motion, a pilot starts experiencing strange feelings and blurred vision. For example, upon facing hypoxia, a pilot may start experiencing narrow visions while the piloting instruments start having a frizzy appearance. Also, as the pilot moves higher, his or her lips and skin under the fingernails start turning blue while the heartbeat presents palpitations.

This effect disorients the pilot’s concentration which results in aircraft accidents. For example, Boeing 747-206B aircraft involved an accident caused by hypoxia experienced by the operator KLM Royal Dutch airlines. The flight originated from Schiphol airport in Amsterdam Netherlands it was meant to land at Gran Canaria airport but crashed on the way leading to a total loss of 248 fatalities.

Hypoxia also has adverse effects on psychomotor performance. This means that when a pilot experiences hypoxia, he or she losses ideology and coordination of the aircraft. Due to these impairments, a pilot cannot be able to control the aircraft since it requires a sober mind free from destruction. Referring to the body effects of hypoxia, it has been observed that loss of consciousness is one of oxygen starvation effect.(Ali and Darnel  2017, P, 446-505) explains that this oxygen starvation can make the pilot collapse leaving the aircraft unattended.

This causes the aircraft to descend and crush resulting to the death of the people in flight. Hypoxia also instills fatigue to the pilots leading to poor psychomotor performance. Where the fatigue generated, cause drowsiness resulting to poor concentration. This fatigue might also cause the pilot not to notice the direction of flight thereby facing sudden collisions. It is also outlined that, it is hard to note the onset of hypoxia. This is put forth by the fact that Hypoxia creates euphoria which refers to the abnormal excitement. This excitement can make the pilot fry higher above the stipulated level. In these regions, hypoxia is more severe since air pressure reduces with increase in altitude, and also goes hand in hand with the pressure of oxygen.

Examples of Accidents caused by Hypoxia

 The following are examples of accidents that happened as a result of the gradual onset of hypoxia. In 2005, an aircraft B733 en –route from northwest of Athens Greece crashed when it descended as a result of exhaustion of fuel. During this incident, 115 passengers and six crews perished due to lack of pressurization. This happened when the crew was engulfed by hypoxia leaving the flight under control of the autopilot and management computer whose rescue actions failed. 

Secondly, the research has it that in 2007, a flight named RJ1H en route from South West of Stockholm Sweden crashed after the crew perished as a result of depressurization. Hypoxia disaster is still a threat even today since flight operations are not still fully equipped with the measures meant to curb it. For example, use of advanced oxygen disciplines such as cabin pressurization is not yet embraced.

 The disaster is said to remain a hindrance in aircraft operations since flight passengers are not always fully equipped with oxygen backups. As discussed in his book (Rabotyagov 2014, P, 58-79) it is found that this may be due to lack of sufficient funds to purchase this commodity and failure of manufacturers to install oxygen gadgets in flights. Negligence by the flight crews to observe the level of altitudes is another factor that encourages hypoxia to happen frequently. This happens such that pilots fail to note the impact they are to make by frying higher above the recommended altitude level. 

Economic needs also make hypoxia remain a threat today since every commercial aircraft operation is based on minimum expense cost. Following this idea, pilots are advised to fry higher above where the flight can move faster and burn little fuel since as the flight climbs above, the air gets thinner, therefore, enhancing fast movement of the flight. Since most aircraft operators are more inclined in reaping the benefit of fast and economical movement, they easily forget that in high altitudes Hypoxia is most severe.

In these regions, there exists insufficient oxygen to fuel the flight engine, and pressurize the air inside the flight. This leads to malfunction of the pilot resulting in accidents. Therefore, need to economize commercial aircraft operations facilitate the existence of hypoxia as a hazardous threat. Due to heavy traffic that exist in lower flight aircraft routes, most pilots tend to fly higher to avoid airborne traffic and other distractions such as moving birds.

Factors Encouraging the Occurrence of Hypoxia

 As they do so, they keep on increasing chances of hypoxia since as seen earlier hypoxia gradually increases with increase in altitude due to the reduction of pressure in oxygen molecule. As far as these traffics remain to be evaded, hypoxia remains a threat even today. Furthermore, in his publication, (Gatterrer2014, P, 731) narrates that in the event of emergencies; pilots tend to fry higher trying to stabilize as the situation gets addressed by the autopilot and computer management.  As this happens, hypoxia disaster may also happen to make the plane crew to collapse and land with an explosion. Therefore, where empirical and critical control of the flight by the autopilot personnel is undermined, Hypoxia remains to be a threat even today since cases of emergency shall keep on recurring.

Lack of adequate training of aircraft personnel is another factor that encourages hypoxia to remain a threat till today. It happens that the cost of competent training for pilots and autopilot personnel is so high such that people opt for shortcuts which give them partial knowledge of aircraft operations. ( Kotliar 2014 P, 763-772) outlines that, this is the reason behind some pilots would fry higher above the recommended level to suit their excitement without realizing that there are risks of hypoxia associated with high altitudes. 

Failure to observe the methods implicated on making the conditioned air is also a thriving factor enhancing existence of hypoxia as a threat today. Cabin pressurization is a process of feeding conditioned air in the cabin of an aircraft requires careful attention to prevent failure. The conditioned air is processed through some activities. Studies by (Legg 2014, P, 126-140) Shows that these activities include, blending off the air from gas turbines then compressing it to gain high pressure.

This gas is then humidified cooled, and recirculated air is then mixed before distribution to the cabin. Since some companies fail to speculate and observe one of these procedures of air installation, the cabin of aircraft still fails to provide the conditioned air at a high altitude leading to suffocation of the passengers on the flight. Therefore, as (lynch 2017, P, 295-303) concludes, Carelessness of the manufacturers of these aircraft cabins facilitates hypoxia to remain a threat even today.

Global warming is another hindrance facilitating the existence of hypoxia where the existing weather condition doesn’t facilitate aircraft operation.(Mahoney 2014,P,45-56) Explained that this is because global warming has resulted in changes in the formation of clouds and air composition in the aircraft routes. This effect forces the pilots to fry higher to evade congestions. While trying to evade this climate conditions, the pilots end up facing hypoxia as they fly higher and higher. Therefore, as far as global warming exists, hypoxia remains to be a threat even today.

Despite its existence, there are measures which can be put in place to protect against it. Malle (2013, P, 773-779) proposed that Carrying oxygen in the plane as a backup is one of the measures that can be put in place to protect against hypoxia. This includes installing conditioned air in the cabin of an aircraft through cabin pressurization. This oxygen can be used in flight which fries above 12500 feet where hypoxia is likely to occur. It can also be used when having night flights above 5000 feet.

Another measure that can be applied to curb hypoxia is obeying the recommended route and altitude. That is, frying within or below 12500 feet. This can help evade limitations associated with a reduction of oxygen pressure which causes hypoxia.in his journal Martinussen 2017, P, 456-556) stated clearly that “both vocational and professional training is a fundamental practice that can help alleviate the hypoxia disaster.” This is made possible whereby the vocational training equips the crews with advanced experience in practical skills of aircraft operations. This includes both autopilot and computer management.

 On the other hand, professional training equips the crew with knowledge and competent skills in both aircraft operations and climate conditions. For example, following an article by (Ostheimer2014, P, 276) it is found that the training offers a good understanding of the aircraft routes, weather conditions and safety measures of operation such as oxygen mask donning in the event of hypoxia. When crews are equipped with a good understanding of these operations, hypoxia can be protected from happening, as well as reduce accident incidents brought about by hypoxia disaster.

Observing weather conditions can help protect against hypoxia. This can be done through processes such as preflight which is a preliminary test on the climate situation before the actual flight operation as explained in a book section by ( Rotta 2014, P,360-363).During this pre-flight, identification of altitudes with icing conditions, towering cumulus and turbulence can be determined to locate the safest zone to follow. When these preliminary activities are carried, hypoxia alleviated.

 In his statement (Schindler 2017, P, 67-71) asserts that High-performance gliding is a method that can be applied to curb hypoxia where a pilot descends rapidly upon crossing a terrain this helps evade high altitudes associated with hypoxia, and also preserve backup oxygen for more altitude areas. If the crew is skilled enough to exercise this, chances of hypoxia can be eliminated.

During the flight, passengers should be addressed sufficiently to have technical skills to identify chances of hypoxia. For example (Shankran 2014, P, 2629) proposed that this gadget can be mounted with additional equipment such as such as pulse ox meters. This gadget measures oxygen content in the blood. A sensor device is mounted on them that clip the fingertips. They give immediate readings where 100 percent represents a normal reading while 95 percent indicates the minimum expected value. Below 90 percent, the device gives a warning indicating the presence of hypoxia. Providing passengers with these additional devices can help alleviate hypoxia disaster since the warning signs indicated by this device can prompt immediate safety measures such as rapid descending.

Use of Automatic Descent Mode, (ADM) in aircraft, can help solve the hypoxia disaster. This happens in such a way that when depressurization occurs at high altitudes, the ADM gives the passengers a chance to engage in other activities. The activities engaged in include identifying the safest path to follow and staying conscious of the changes. Following a study by (Temme 2017, P, 101-105) it is clear that when this hypoxia phenomenon happens, the computer management that is, the autopilot department guides the aircraft to approach safest altitudes with at with a high velocity. 

The ADM activation is done when the autopilot is engaged in guiding the flight. This is normally done when the flight is 30,000 feet above, and the cabin is at an altitude of 9700 feet or more as reported by (Winslow 2015, P, 693-701). The ADM helps alleviate the hypoxia disaster by guiding the flight through a specified mechanism.

To start with, the ADM guides the flight to turn 90 degrees left. This helps the flight to partially leaving the altitude with depressurization. Secondly, the Autothrottle is automatically engaged when required to reduce the thrust to a resting position. The ADM also makes the flight descend with a relative speed of 10kts lesser than Vmo/Mmo.

Before deciding on which altitude to follow a pre-selection of 15000 ft. Altitude is first tested then the ADM is expressed in the middle of the FMA panel. In his article, Zafren (2014, P, 29-39) outlined that When the aircraft reaches 15000ft, it maintains a speed of 250kts, and the ADM remains in control until the autopilot is withdrawn. In conclusion, ADM operation supports hypoxia protection by improving safety operations in aircraft, reducing the workload to the crews in flight and also fully automating the flight system.

Reference list

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