Page 8 - Module 9 Look Inside

In 2003, Flight International reported that ‘technical/maintenance failure’ emerged as the leading
cause of airline accidents and fatalities, surpassing controlled flight into terrain, which had
previously been the predominant cause of airline accidents. According to former NTSB Board
member John Goglia, deficient maintenance has been implicated in 7 of 14 recent airline
accidents.

Maintenance errors not only pose a threat to flight safety, but can also impose significant
financial costs through delays, cancellations, diversions, and other schedule disruptions. For
example, in the case of a large aircraft such as a Boeing 747-400, a flight cancellation can cost
the airline around 140,000 Euros, while a delay at the gate can cost an average of 17,000
Euros per hour. In this context it can be seen that even simple errors such as gear pins left in
place, requiring a return to gate, can involve significant costs. Even a small reduction in the
frequency of maintenance-induced schedule disruptions can result in major savings.

What is ‘human factors’?

The term ‘human factors’ is used in many different ways in the aviation industry.

The term is, perhaps, best known in the context of aircraft cockpit design and crew resource
management (CRM). However, those activities constitute only a small percentage of aviation-
related human factors, as broadly speaking it concerns any consideration of human involvement
in aviation.

‘Human factors’ refers to the study of human capabilities and limitations in the workplace.
Human factors researchers study system performance. That is, they study the interaction of
maintenance personnel, the equipment they use, the written and verbal procedures and
rules they follow, and the environmental conditions of any system. The aim of human factors
is to optimise the relationship between maintenance personnel and systems with a view to
improving safety, efficiency and well-being.

Thus, human factors include such attributes as:

 human physiology
 psychology (including perception, cognition, memory, social interaction, error)
 work place design;
 environmental conditions
 human-machine interface
 anthropometrics (the scientific study of measurements of the human body).

The use of the term human factors in the context of aviation maintenance engineering is
relatively new. Aircraft accidents such as that to the Aloha aircraft in the USA in 1988 and the
BAC 1-11 windscreen accident in the UK in June 1990 brought the need to address human
factors issues in this environment into sharp focus. This does not imply that human factors
issues were not present before these dates nor that human error did not contribute to other
incidents; merely that it took an accident to draw attention to human factors problems and
potential solutions.

Total Training Support Ltd 1-9 Issue 2 – September 2016
© Copyright 2016 Module 9.1 General