What the ATSB found
The requirement to ditch resulted from incomplete pre-flight and en route planning
and the flight crew not assessing before it was too late to divert that a safe landing
could not be assured. The crew’s assessment of their fuel situation, the worsening
weather at Norfolk Island and the achievability of alternate destinations led to their
decision to continue, rather than divert to a suitable alternate.
The operator’s procedures and flight planning guidance managed risk consistent
with regulatory provisions but did not minimise the risks associated with
aeromedical operations to remote islands. In addition, clearer guidance on the in-
flight management of previously unforecast, but deteriorating, destination weather
might have assisted the crew to consider and plan their diversion options earlier.
The occupants’ exit from the immersed aircraft was facilitated by their prior wet
drill and helicopter underwater escape training. Their subsequent rescue was made
difficult by lack of information about the ditching location and there was a
substantial risk that it might not have had a positive outcome.
What else should ATSB have found?