Human factors in aviation safety
The commercial aviation industry has considered "human factors" as a main element to safety, because of the increasing number of accident or incident caused by human errorsrather than mechanical failure. Human factors is often considered with crew resource management (CRM) or maintenance resource management (MRM). The study of human factors in aviation involves human performance, limitations and other characteristics, and how they can integrate with the technology to achieve safety and efficiency. That understanding is then translated into organisational factors which inlcude design, training, policies, or procedures to help humans perform better. (Human Factors, (2009)1)
Organisational factors in aviation safety
Human factors has moved beyond the individual and even the group nowadays. It is seen include the nature of the organisation that design, manufacture, operate, and evaluate aviation systems, it plays the key role to shape human factors. Accidents and incidents can be seen as a breakdown of the organization. If the pilots are the direct cause of errors on flight deck, then these organizational failures are the root cause and latent errors which can shake the safety from its fundation. Organisational factors include policy, organizational culture, management support, maintenance and training etc. Therefore, organisations' duties are to recognise problems, take actions and make corrections for future safety. (Thaden & Wiegmann, 20042)
Reason’s “Swiss Cheese Model” has stated the relationships between organizational factors and flight safety.
Reason's "Swiss Cheese Model"
(Picture embeded from Human Environment Analysis and Design on 21 August 2009)
Airline safety data sources
In order to recognise problem and take actions, airlines need to understand what caused them to move from the centre to the edges of the “safety square”. This is accomplished by collecting and processing performance data from accidents, incidents and nomral flight operations. (Klinect, 20053)
Accidents: loss of life, serious injuries, irreparable structural damage to an aircraft.
Accident Data: obtained from a formal investigation, it is usually conducted by governmental safety agencies. Sometimes it requires years and large amount of resources for one accident, it is expensive and time consuming.
Incidents: for example, near-midair collision of two aircrafts approaching each other on the same altitude or a runway incursion. Incidents are highly visible when they occur.
Incident data: rely largely on pilot self-report to mandatory or voluntary reporting systems. However these reporting tend to provide data on aircraft malfunctions with little or no data on human factors performance issues, due to the pilots’ fears of disciplinary action.
Normal operations: all flights not resulting in an accident or incident are considered normal operations.
Normal operation data: the primary data sources are quick access recorderers and line checks. QAR can create huge amount of data, it is hard for airlines to absorb and analyse, and there’s no information about environment or flight crew performance issues. Line checks are best for uncovering proficiency issues but do not portray an accurate snapshot of flight crew behaviours in normal operations.
LOSA as a proactive safety measurement
LOSA is designed to collect data on human factors from crew performance, and then analyse and understand the organisational factors behind the occurances by involving all possible organisations and personnelsin the audit process. It works as a proactive safety measure which collects data that is independent of flight outcome, and data are collected from flight in normal operations. The data collected during a LOSA can impact almost every department in an airline, table below shows how they maybe affected and eveluated:
|Indentify threats in the airline’s operating environment||Adverse weather, airport conditions, traffic congestion; flight crew’s coping strategies.|
|Identify threats from within the airline’s operations||Operational time pressure; dispatch errors; aircraft malfunction; problems with ground, ramp, maintenance; cabin personnel|
|Access the degree of transference of training to the line||Information can be reviewed from a traning perspective to understand which training areas are not transferring successully to the line.|
|Check the quality and usability of the procedures||Locate problematic procedures and policies via poor adherence rates.|
|Identify design problems in the human-machine interface||Aircraft handling and automation errors in different fleets can highlight systemic flaws in design, interface or adaptation.|
|Understand Pilots’ shortcuts and workarounds||Capture collective expertise from within the pilot group and share it through formal airline communication channels.|
|Access safety margins||How close the airline is operating to the edge of the safety envelope without crossing the boundray into accident or incident.|
|Provide a baseline for organisational change||Whether the organisational change is effective in reducing threats and errors.|
|Provide a rationale for allocation of resources||Provide a data-driven rationale for prioritizing and allocating scarce organisatonal resourcestowards interventions.|
(The University of Texas, 20044)
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