Civil Engineering Reference
In-Depth Information
COMMUNICATION BREAKDOWN
There are frequently communication breakdowns in the cockpit (Wiener and Nagel,
1988; Wiener, Kanki, and Helmreich, 1993). The main problem is that the captain and the
first officer do not communicate appropriately. This was a contributing reason for the Air
Florida flight that crashed into the 14th Street Bridge over the Potomac River in
Washington D.C. in January 1982. Seventy-eight persons died. It was discovered that the
cause of the crash was that the plane's wings were covered with frozen ice just prior to
the crash. Despite the freezing weather and snowy conditions, the crew failed to activate
the anti-ice systems. Some blame was put on the captain and first officer, since they did
not communicate about the icing problems.
Although there may be several reasons for this behavior, one common reason is the
difference in status. Sometimes the captain is dominating and the first officer is
submissive (common in Asia). To break down this barrier, flight crews around the world
are today given annual training in crew resource management (CRM). For example, when
a captain first meets the flight crew he must immediately try to develop a friendly and
trusting atmosphere. This can be done by talking to the other crew members and inviting
a discussion regarding flight related matters.
JAMES REASON'S TERMINOLOGY
James Reason's (1990) model can help in consolidating many of the issues that we have
discussed. According to Reason there are three different types of human errors: mistakes,
slips, and lapses or mode errors. Figure 18.5 shows a flow diagram of human information
processing. An operator will perceive a stimulus which must be interpreted, and she then
makes an assessment of the situation. The operator then formulates a plan for action, and
finally executes an action. There are two types of mistakes: knowledge-based mistakes
and rule-based mistakes. These result in failure to formulate the right intention or plan for
action. They depend on shortcomings in perception, memory, and information
processing.
James Reason used Jens Rasmussen's (1986) distinction between knowledgebased
mistakes and rule-based mistakes. Knowledge-based mistakes occur when an operator
lacks knowledge and therefore cannot interpret what is going on. As a result the operator
is overwhelmed by the complexity of evidence and cannot interpret the information
correctly. Take, for example, a scenario in a nuclear power plant when something goes
wrong. There are hundreds of alarms, both auditory and visual, and the operator has great
difficulty in understanding what is going on and what actions to take. An inexperienced
operator may simply not have enough knowledge about the functionality of the plant. An
operator is well aware of his lack of knowledge, and after he comitted an error, he will
testify that the accident was his fault, because he did not have enough knowledge.
