This Review was commissioned by the Civil Aviation Authority following recommendations
made after the helicopter crash at the Cormorant Alpha platform in 1992. It addresses all
aspects of offshore helicopter safety and survival in the context of an integrated system,
with the intention of maximising the prospects of occupants surviving a helicopter accident
at sea. It does not address the causes or prevention of helicopter accidents.
The Review is based upon an Event Tree, which is a diagrammatic representation of an
offshore helicopter flight, depicting a number of significant points (or ‘nodes’) where
something might go wrong. The Event Tree thus illustrates all the major possibilities
including a safe flight, a ditching, a crash (with or without warning), the subsequent
flotation or sinking of the aircraft, the availability or otherwise of liferafts, the functioning of
personal safety equipment and the rescue process. The Event Tree is depicted at Annex J.
The Event Tree is then developed into a System Table, which is a tabular listing of all the
significant events in the history of a helicopter accident, grouped into seven phases
commencing with departure from base and ending with rescue from the sea. A number of
elements are identified within each event, and each is analysed in turn in Sections 6 to 12 of
the report, where specific deficiencies and possible remedies are discussed. The System
Table appears in full at Annex K.
The penultimate section of the report contains an overall assessment of the present safety
and survival system. It points to the 100% success record of survival after ditchings and the
inevitably less favourable record of crash survival; it suggests the need for greater emphasis
on safety measures related to heavy impacts as opposed to ditchings, but cautions against
prejudicing ditching survival in an unrealistic attempt to help the victims of non-survivable
crashes.
The report concludes with 17 recommendations. There are few, if any, radical proposals. For
the most part, the report endorses work which is already in hand or nearing completion;
however, it identifies a number of areas where further studies need to be initiated or where
existing work needs to be coordinated or given more urgency. Conversely, it considers and
dismisses as impracticable two proposals which have gained currency - the provision of
underwater breathing apparatus and the prohibition of offshore flights in weather
unsuitable for ditching. The report does, however, make a positive proposal for a more
methodical way of ensuring that offshore managers appreciate the relationship between the
time it would take to rescue survivors of a crash and the time they could be expected to
survive in the water in the prevailing conditions.