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Old 5th Dec 2003, 04:05
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OverRun
Prof. Airport Engineer
 
Join Date: Oct 2000
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BASI (1991) The Limitations of See and Avoid, Research Report, Bureau of Air Safety Investigation, Canberra. April 1991. ISBN 0 642 16089 9

Not available electronically as far as I know. E-mail me if you search and can't get a paper copy on account of the fact it has suddenly 'disappeared'.

Amongst its findings:
A traffic search in the absence of traffic information is less likely to be successful than a search where traffic information has been provided because knowing where to look greatly increases the chance of sighting the traffic (Edwards and Harris 1972).

Field trials conducted by John Andrews found that in the absence of a traffic alert, the probability of sighting a threat aircraft is generally low until a short time before impact. Traffic alerts were found to increase search effectiveness by a factor of eight. A traffic alert from ATS or from a radio listening watch is likely to be similarly effective (Andrews 1977, Andrews 1984, Andrews 1987).

One of the recommendations of that report was that 'pilots should recognise that they cannot rely entirely on vision to avoid collisions. Consequently, they should attempt to obtain all available traffic information, whether from Air Traffic Services or a listening watch, to enable them to conduct a directed traffic search.


However your thought that it's VERY IMPORTANT that the powers-that-be understand that relying on see-and-avoid (....) is flawed is probably going to be unfulfilled. One of the conclusions of the BASI 1999 INVESTIGATION REPORT B98/166 Systemic Investigation into the Class G Airspace Demonstration, pertained to the powers-that-be, and it was that
The following organisational factors adversely influenced the ability of CASA to effectively
manage the Class G demonstration project:
• There was a lack of established processes within CASA for conducting safety case and
consultation activities for large change-management projects.
• CASA’s management profile and staffing prior to July 1998 reduced the ability of the
organisation to effectively monitor and control its activities.
• There was a lack of appropriate internal and external review mechanisms for ensuring the
objectivity of the project.
• The division of roles and responsibilities between CASA and Airservices Australia regarding the
design and regulation of airspace was not clearly defined.
• The division of roles and responsibilities between the CASA Chairman and the Director and
other management was not clearly defined.
• The influence of the CASA Chairman’s involvement in airspace reform and management style
contributed to the project management deficiencies associated with the demonstration.
The only thing that seems to have changed is that Dick is no longer the Chairman, but he is still involved in airspace reform and the collective Smiths' management styles have very heavily contributed to the project management deficiencies associated with the present NAS introduction.

Let me finish with this marvellous quote from the 1999 BASI report which seems as relevant today as it was then
The Chairman’s close involvement in project management became associated
with a number of undesirable consequences, including:
• the removal of previous internal review processes, including important review mechanisms
at higher levels than the decision-maker;
• a decrease in the ability of CASA managers, and the organisation as a whole, to coordinate
their decision-making processes;
• an increase in confusion among staff and external parties regarding who in CASA was
making decisions, and what decisions were valid; and
• uncertainty among CASA staff regarding their ability to query the Chairman’s decisions or
instructions due to his senior position.
It was subsequently reported by CASA staff that the Chairman’s management style was
characterised by micro-management, an unwillingness to consider other views, and rigid
adherence to a pre-determined path. The Chairman also appeared to show a low level of
interest in activities that could lead to delays in the implementation process.
Many of the problems associated with the planning and implementation of the demonstration
were related to inadequate safety analysis, consultation and education activities. Although
there were many reasons for the problems encountered, there is considerable evidence to
indicate that the influence of the Chairman’s active involvement and management style
contributed to those problems.
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