Factors Affecting Aviation Safety - Research Paper Example

 Factors Affecting Aviation safety Abstract Aviation is an elite but expensive experience enterprise. ‘Stay alert and stay alive’ is the thumb rule; and yet military aviation is the back bone of a nation’s defense efforts. In this backdrop a complacent moment could be excruciating. For maintaining one’s demeanor parallel to one’s repute, any Air Force must be a safe Force (Air safety, 2010). Besides, numerically small air forces can hardly withstand attrition. Common denominators in world Aviation safety data over the years in my view come out to be: 1. Human factor (maintenance) 2. Ageing fleet It is a universal truth that as a system ages, it nags more. Operators and supervisors, therefore, must be extra vigilant and patient with old systems. On the positive side, old systems have long history and thus precious experienced hands. They need to be utilized in order to answer the “why” part. And thus a logical mix of extra care and intelligent resort to experience can turn the same machines from old to gold. Human factor The human aspect of the safety equation had been long ignored in the safety business. However, during the recent past, human factor has drawn significant attention of the safety specialists. Understanding humans, their limitations and reasons behind human failure is no longer a secondary preference. Today, human factor is the focal point for most of the safety research. Understanding this most complicated machine designed by God is not an easy task and requires dedicated endeavors in the realms of designing, operations, physiology and psychology. Due to complexity of the subject, human factor is rightly quoted as the last frontier to be conquered in the battle of aviation safety. We must realize that active failure of the operator in most of the accidents is just a symptom of the actual fault. Our actual worry is the latent failures which may remain dormant within a functional system for years and weaken the safeguards placed to protect the system against a disaster. To avoid the active failures, these latent failures must be located and factors responsible for these failures must be removed from the system. The process, however, is complicated and requires a major change in our thinking and investigation procedures. Awareness, however, is the first step towards any change. Maintenance errors cost an Air Force millions of dollars each year in term of rework and replacement, and present potential safety concerns (Alexander & Clarence, 2004). Following are the 12 primary reasons which in my view are causes for such errors: 1. Lack of communication 2. Complacency 3. Lack of knowledge 4. Distraction 5. Lack of teamwork 6. Fatigue 7. Pressure 8. Lack of resources 9. Lack of assertiveness 10. Stress 11. Lack of awareness 12. “Destructive” workplace norms Usual efforts to investigate errors are often meant to identify the technician who made the error. The normal result is that the technician is defensive and is subject to a combination of disciplinary action and re-training. Since retraining often adds little or no value to what the technician already knows, it is ineffective in preventing future errors. Additionally, by the time the technician is identified, information about the factors that contributed to the error has been lost. As the factors, (that contributed to the error) remain unchanged, the error is likely to recur, setting the “blame and train” cycle in motion again. In order to prevent maintenance errors, it is essential that, we as investigators learn to look for the factors that contributed to the error, rather than the person who made the error (Amalberti & Wioland, 1997). Our investigation should be based on the following philosophy: Positive Intent i.e. technicians want to do the best job possible and do not make errors intentionally. Contribution of Multiple Factors i.e. a series of factors contributes to an error. Manageability of Errors implies that most of the factors that contribute to an error can be managed. Unfortunately, too often I find that some technicians feel that it is up to their superiors to make sure that maintenance errors do not occur. These technicians cite such factors as unrealistic time lines, lack of proper resources, hanger/pen lighting, lack of spares and the list goes on. I, however, believe that every technician must accept individual responsibility for his actions, work product, professional growth, continuous training and self-improvement. Every technician ought to be accountable for his own actions. As the maintainers of complex aircraft, we must be aware of the factors that can adversely affect our judgment at critical moments in our day to day routine. We must be aware of how our own attitude, self esteem, stress, distractions and lack of knowledge affect our judgment. Knowing this, we can better understand what counter measures we need to implement in our team work routine to make sure we are not creating maintenance errors and that we reduce the possibility of such errors occurring in the future. Communication is crucial – it is the foundation for nearly everything we do, not just on the job but also throughout our daily lives. Attitude as well is extremely important. An individual who comes to work well with high self esteem is able to work well with others because of his self image. Regardless of what happens during the day, he knows that he has tried the best he can to take decisions, look for the good in others’ actions, and takes criticism constructively. A positive attitude is contagious in a good way. This is a basic starting point that one should come to work with a positive attitude and high self esteem. If you find that you just cannot muster a positive attitude and feel good about yourself, then perhaps you should consider some changes in your life that will help to create this positive attitude. Complacency, Pressure, Stress, and distraction can negatively affect our judgment. We have to make sure that these human factors do not take root in our personal’s behavior. A relatively easy concept, which does not cost any money and does not require a directive or policy, is for each of us to take pride in our signature. Our signature is a written testimony of our individual accountability. How many people do we know who will sign something just for the sake of signing? If we read and visualize everything that we do before we sign for the task, there would be a marked decrease in errors. Do not sign to clear an entry without first reviewing in your mind everything that you did. Make this a permanent habit and you will have implemented a very strong counter measure to human errors. As professionals we are accountable to ourselves to stay knowledgeable in our fields. We should do a self audit to determine areas that we need to improve and study. When we look at aviation accidents reports or read articles on accidents, we find that from time to time a distraction affected the judgment of maintenance technicians or supervisors. Distractions are a common occurrence in all of our lives, both at home and at work. But if distractions occur in a critical phase of our work, they can have disastrous consequences. Psychologists have identified distractions as the number one cause of forgetting. Again, in addition to distraction, if other factors are present such as fatigue and stress, then the likelihood of an error occurring will increase manifolds. We have to rely on each other when it comes to distractions. A few easy to follow safety nets can go a long way in preventing both minor and major incidents. These include: Support each other and work together as a team. Put it in writing. The written word is a valuable safety net especially for the distraction of shift changeover. Follow the work cards and check sheets. Document the work you have completed as you progress through the task. When you come back to a job take three steps back and evaluate what is not done. Do not let complacency reduce your standards. Take pride in your work Bad habits, which in many cases have become norms in general routine include: Pushing/towing an aircraft with no one riding the brake. Moving an aircraft without wing walkers. Assuming consumable fluids are in their right dispensers and containers. What can we do? Here are a few simple ways to combat the development and / or existence of unhealthy habits: Look for the norms where you live and work. Be aware that “norms” do not “make right”. If the habit is only yours and it is negative, then work on removing it before it becomes a group norm. Work to accentuate the positive and eliminate the negative as a group. Always work in accordance with the approved manuals and check lists. Read everything you sign for – take pride in what your signature represents. The existence of a norm and the attitude that flows from it are significant. They can lead to promoting productivity and safety or restricting output. They can also assist in making decisions promptly or stifle opportunities, resulting in delays and creating untoward incidents. Ageing fleets An aircraft begins to ‘age’ as soon as it first flies and various effects begin to occur. However, the term is usually applied to the issues which can begin to arise as the time-since-new becomes significant – and greater than the average age of similar-class aircraft. All air forces with limited resources have a record of pushing the limits on air craft life. Likewise, we do not retire our tools until they beg for mercy killing, whereas we should have respectfully buried those years before with full honors, and brought new ones in their place. It may be the nostalgia of keeping my favorite screwdriver until the Philips end changes to a chisel, or it could be my ingrained fear that parting with my lucky screwdriver would bring bad luck, or could it be the psyche at the back of our technicians’ mind that each screwdriver costs a lot- that too in dollars. Whatever the reason may be, we like our equipment to outlive us. Aircraft is a complicated machine. It has a wide variety of components, ranging from metallic panels, to rubber hoses, to thin wires, to high quality HUD glasses and complicated avionics. The variety is bewildering. Reliability and maintainability of all this mishmash varies just as much. With such an amalgam of components, it is but a natural that as the aircraft ages, its maintenance workload increases. Parts that get old start to leak; some develop cracks that were never anticipated. No aircraft is designed to operate for 50 years, and yet we make it to. But with the decision to fly the aircraft for so long, we must weigh the accompanying increase in risks, workload in its upkeep and operating cost (Ageing aircraft used to study longevity of composites, 2005). Statistically, the flight safety risks, maintenance workload and costs of spares, all increases with the age of the aircraft. Obsolescence also adds to the cost of spares as they become uneconomical for the manufacturer who has to use old techniques to manufacture old technology components. Late upgrades to pre-empt failures cost even more on ageing aircraft. Nevertheless, the decreasing MTBF (Mean time between failures) is not uniform across the components over a long life. There are components (such as tyres and drag chutes) that are designed for a limited number of sorties, and there are aircraft panels that are designed to last thousands of hours. Life expired aircraft pitched in parks and in roundabouts are a testimony to extremely strong materials in construction of their basic structure, skin and panels. As long as the aircrafts are new, they perform like the Ferrari that comes with a 50,000 km unconditional warranty. But on the ageing aircraft the warranty is a long forgotten promise. The big question for these aircrafts is how to predict and avoid failure of a component without losing an important part of its life? It is easy to remove a component and put it in a repair cycle, or altogether reject it, thinking that it might fail in a couple of weeks. But how to make that judgment without knowing the complete affects of that decision? The manufacturer gives a certain life to an aircraft based on certain operating conditions. The design engineer does not know in which conditions operator is going to utilize the aircraft, while it flies in hot and humid, cold with high elevation, and corrosive conditions of the coast. With this comes the enormous burden of ensuring aircrafts best utilization while balancing cost of maintenance against life of a pilot. With such variance between the design and operating conditions of ageing aircraft, arises the silent whimper of the ageing aircraft, which shows as little material failures that never happened before. Every new crack, every new leak is saying that the aircraft needs more than regular care. It needs meticulous inspections like never before. It needs that second look just in case you missed the silent tears from the sobbing fuel hose, or the bleeding from the hydraulic fluid connection in your first glance. Metallic corrosion is a major factor in accentuating the ageing phenomenon of an aircraft. Metallic Corrosion occurs when chemical action causes deterioration of the surface of a metal. Most corrosion is galvanic or electrolytic in origin, which means that it has occurred because two dissimilar metals have been together in an electrolyte (usually contaminated water). This effect can also occur at the microscopic grain boundaries within a metal alloy. How may ever it arises, it may go undetected and result in loss of integrity of metallic structures. Prevention in the long term will be by better design and selection of materials, which nowadays include proven non metallic composites precisely. There is also a need for better understanding the detailed effects of corrosion on structural integrity. Chronological age is especially relevant to corrosion incidence, as is the ground environment where an aircraft is usually parked as well as the typical flight environment. For existing aircraft, improved inspections, including the use of non-destructive testing (NDT), and the management of any corrosion found through effective repair techniques, mapping technologies, and recording are the main option. Common NDT methods include ultrasonic, magnetic-particle, liquid penetrant, radiographic, and eddy-current testing. The possibility of structural fatigue from any origin has been actively considered since the advent of pressurized aircraft when there were accidents attributable to an insufficient understanding of some basic design issues. Since then, aircraft design procedures have involved the carefully-researched creation of structures which will withstand a stated number of flight cycles and/or flight hours with a low probability that the strength of the structure will degrade below its designed ultimate strength before the end of its approved life. However, sometimes older structures are found to no longer meet their damage tolerance requirements because repeated cyclic or exceptional ‘g’ loading has unexpectedly produced cracks of a sufficient size and density in a structure to weaken it so much that it no longer has the intended residual strength. This may happen not just in metals but other materials increasingly used in aircraft construction. The only available defense is better detection inspections during base maintenance including the use of NDT. In some cases, this means proper application of existing maintenance procedures, especially in respect of repairs; but in other cases, the specification and oversight of those procedures has been such as to make detection of dangerous levels of structural fatigue unlikely, especially when a direct or indirect consequence of a repair (Ageing aircraft, 2009). The mechanism by which fatigue propagates in a structure is the well known crack. Cracks propagate because the geometry of a crack produces a very high concentration of stress at the end of the crack and eventually, if a growing crack goes undetected, fracture will occur. Fatigue cracks have been found to arise in three main ways: In internal load-bearing airframe structural components which can develop stress ‘hot spots’; In load bearing skins of large aircraft in which the skin itself carries a significant structural load; From fastener holes such as those for rivets, bolts, nuts and screws where localized stress concentration can initiate premature cracking. Conclusion Every year brings with it an insidious upturn of the accident rate curve in one way or the other. What are the reasons? Is it the smug pride we take in the so called justified safe achievements of previous years or a mistaken resort to complacency that unfortunately follows a good period? One lesson is surely learnt that maintaining safe trends is perhaps even harder than achieving them in the first place. But even so often that we find ourselves in this wrong position of the trend, vigilance against hazards has to be in multiple dimensions. Every now and then, one comes across an example of a safety program that could be emulated. In the UK, there is a program known as CHIRP, for Confidential Human Factors Incident Reporting Program, in which pilots, flight attendants, air traffic controllers and mechanics can anonymously report safety problems (Copying a good idea, 2009). In my view, more use of composite materials to cater for ageing factor and the idea of confidentiality as mentioned above in CHIRP can in actuality make discernible change in our effort towards aviation safety. References Ageing Aircraft - Structural Failure (2009). Retrieved from http://www.skybrary.aero/index.php/ Ageing_Aircraft_-_Structural_Failure Ageing aircraft used to study longevity of composites (Aerospace). (2005.) In Advanced Composites Bulletin, Retrieved from http://www.encyclopedia.com/doc/1G1- 126717628.html Air Safety. (n.d.). Retrieved February 03, 2010, from http://en.wikipedia.org/wiki/Air_safety Alexander T. Wells & Clarence C. Rodrigues. (2004). Commercial aviation safety (4th ed.). NY, USA: McGraw-Hill. Copying a good idea. (2009). Retrieved from http://asj.nolan-law.com/2009/11/copying-a-good- idea/ R. Amalberti & L. Wioland (1997). Human error in aviation. In H.Soekkha (Ed.), Aviation Safety (pp. 91-108). Ridderkirk, Netherlands: Ridderprint bv. Read More