Safety issue
The process for identifying potential rail defects is limited by
the ultrasonic test vehicle operator's ability to detect and assess
the echo patterns correctly.
Action taken by the ARTC
Rail Technology International (RTI) is actively conducting further
development of their ultrasonic testing process. For example, RTI
are developing software based on 'Artificial Neural Networks' for
recognising ultrasonic reflection patterns that represent potential
rail defects such as bolt-hole cracks. RTI have conducted post test
re-analysis of ultrasonic test data using the neural network
software to identify any defects that may have been missed during
the test run. RTI's plan is to run the neural network software in
the background and conduct this analysis while ultrasonic testing
is being undertaken. RTI have indicated that implementation is
planned for early 2010.
ATSB assessment of action
The ATSB acknowledges that the ARTC and RTI are developing
processes to reduce the risks associated with operator dependence.
While some of those
initiatives have been introduced, especially in relation to
bolt-hole cracks, other rail defects are also exposed to the issue
of operator dependence. The opportunity exists for continued
development and implementation of strategies aimed at reducing
operator dependence.
ATSB safety advisory notice
RO-2008-005-SAN-035
The Australian Transport Safety Bureau advises that the ARTC
should consider the implications of this safety issue and take
action where considered appropriate.