A recent study by the Harvard School of Public Health involving 3500 pilots, revealed that 12.6 per cent of the study group may have clinical depression, and 4.1 per cent reported having suicidal thoughts two weeks prior to the study.
These figures do not make for good reading and will give frequent flyers a reality check. Pilots are not superhuman. The brighter side is that these conditions are attributed to factors outside the cockpit and there are known medical procedures to manage and treat them.
Clinical depression has known symptoms and is visible. It can be noticed by the individual or other crew members in time before they get into the cockpit.
However, there exists an invisible hazard, a serious concern for the aviation industry. It is encountered by most pilots who fly long enough in their career and could set in involuntarily during flight. Worse still, it affects normal pilots- even those with plenty of experience- and is mostly discovered by investigators after fatal accidents.
This is the inability of a pilot to correctly interpret aircraft attitude, altitude or airspeed in relation to the earth or other points of reference.
In order to know the causes of spatial disorientation, there is need to understand spatial orientation. This is the natural ability to maintain body posture or orientation in relation to the surrounding environment; the ability to know when one is sitting, standing, walking, looking up or down, looking left or right.
Spatial orientation is controlled by three systems; visual (eyes), vestibular (balance organs in the ears) and proprioceptive (limbs). When on the ground, a human body coordinates all three with ease. Eyes provide visual reference, canals in the ears are responsible for lateral and vertical direction, pressure on the buttocks is an indicator of sitting while pressure on the feet and ankles is indicative of standing.
The visual system accounts for 80 per cent of spatial orientation while 20 per cent is shared by the other two systems.
Flying over the ocean on a moonless night deprives pilots use of the visual system for orientation. In such instances, and also when visibility is poor during bad weather and low cloud, crew use onboard instruments to navigate.
Pilots must undergo 40 hours of instrument rating training in order for their brains to get accustomed to relying on instruments, without any external visual reference for guidance.
However, competence and confidence to fly with instrument guidance does not completely eliminate the possibility of spatial disorientation. This is because during instrument flight, pilots do not use vision for external references, yet this is their most important orientation system.
Further, the human body is designed to maintain spatial orientation on the ground, not in the cockpit where it is subjected to acceleration and G-forces.
Loss of Situational Awareness
Aircraft accidents are never attributed to a single factor. Investigators consider multiple factors beginning with managerial failure, supervisory failure, factors contributing to the accident, and finally, the actual cause of the accident.
In accidents where spatial disorientation is determined to be a contributing factor, the crash is always preceded by a series of errors and omissions, leading to a high work load and stress.
During this period, pilots are overwhelmed with interpreting aural and visual information, flying the aircraft and coordinating with air traffic control. This places them in a situation conducive to confusion, loss of situational awareness, and ultimately, disorientation.
Using the analogy of a pitch black house where lights have gone out unexpectedly because of a blown fuse, an individual is bound to get confused if, within a space of 20 seconds, he/she has to;
When all this happens at the same time, in the absence of vision, panic and confusion are likely to set in. During the process of moving quickly from one room to another, there is a possibility of missing the exit/entry point and colliding with a wall, chair, door, or missing a step.
The fact that this individual has occupied the same house for many years might count for nothing during the 20 second period. The suddenly high workload leads to confusion and stress, causing the individual to lose situational awareness and forget existence of known obstacles or dangers, like furniture and stairs.
In such a scenario, the individual’s first priority should be to restore vision before attending to other matters. This preempts panic, restores awareness, and averts potential accidents.
It is a lot more complicated for cockpit crew travelling at high speed without external visual references, in close proximity to the ground and with loads of information to process within a short time. Pilots may find themselves operating beyond the limits of the normal human orientation systems, and in the process, failing to manage situations.
Spatial disorientation has been determined to be a contributing factor in a number of air crash accidents. The final investigation reports in respect of Kenya Airways flight 507, Ethiopian Airlines flight 409, Flash Airlines flight 604 and Gulf Air flight 072 have the following in common;
At the time of writing this article, the final report on the crash of Fly Dubai flight 981 has not yet been published. Although the interim report is silent on the matter, the circumstances of the crash, and conduct of the crew as stated in the interim report factual information suggests evidence of spatial disorientation.
Be that as it may, frequent flyers need not worry about night flying or pilot limitations, because air travel is still the safest mode of transport, with ever improving statistics. According to IATA’s 2015 Safety Report, there was one major jet aircraft accident for every 3.1 million flights in 2015, an improvement from one in every 2.2 million flights for the period between 2010 and 2014.
Safety is the aviation industry’s highest priority. It is defined by the International Civil Aviation Organization as,” the state in which the possibility of harm to persons or of property damage is reduced to, and maintained at or below, an acceptable level through a continuing process of hazard identification and safety risk management”.
Despite improvements in aircraft technology and automation, hazards and risks cannot be completely eliminated because of human limitations and the environment in which aircraft operate-altitude, speed, temperature and weather. Risk is part of every flight, and can only be eliminated if planes never take to the skies.
In order to manage risk, airlines make safety part of their corporate culture. They constantly review and update their operating procedures. Crew resource management, human performance, safety management and upset recovery are an integral part of initial and recurrent training programs. Pilots are evaluated through regular medical tests and simulator training. Such training allows them build and maintain situational awareness. They can question their senior colleagues and take command of the aircraft should they observe incapacitation, inappropriate control inputs, or departure from standard operating procedures. It also prepares them for team work and coordination of tasks in the cockpit.
Voluntary non-punitive reporting programs encourage crew to report accidental errors and omissions during flight. This allows airlines document reported hazards, and take corrective action either through training or reviewing operating procedures.
Aircraft manufacturers increasingly involve human factors and biomechanics experts during the cockpit layout and instrument design phase. As a result, modern cockpits have improved ergonomics, and behavioral data is more accurate, thanks to hi-tech simulation.
Certifying agencies support airlines by sending advisory circulars and guidance material should a need to change training, operating or maintenance procedures arise.
Finally, regulatory agencies are vigilant in their oversight function.
While accidents and incidents may not be completely eliminated, the message to frequent flyers is, the air transport industry constantly identifies hazards, takes corrective action, and maintains risks at acceptable levels. Manufacturers, operators, training organizations and regulators work together to deliver the industry’s highest priority.
The skies are a lot safer today, thanks to lessons learned from past tragedies.